@article{perez-diaz_mcfeeters_moeller_johanningsmeier_hayes_fornea_rosenberg_gilbert_custis_beene_et al._2015, title={Commercial Scale Cucumber Fermentations Brined with Calcium Chloride Instead of Sodium Chloride}, volume={80}, ISSN={["1750-3841"]}, DOI={10.1111/1750-3841.13107}, abstractNote={Abstract}, number={12}, journal={JOURNAL OF FOOD SCIENCE}, author={Perez-Diaz, I. M. and McFeeters, R. F. and Moeller, L. and Johanningsmeier, S. D. and Hayes, J. and Fornea, D. S. and Rosenberg, L. and Gilbert, C. and Custis, N. and Beene, K. and et al.}, year={2015}, month={Dec}, pages={M2827–M2836} }
 @article{johanningsmeier_mcfeeters_2015, title={Metabolic footprinting of Lactobacillus buchneri strain LA1147 during anaerobic spoilage of fermented cucumbers}, volume={215}, ISSN={["1879-3460"]}, DOI={10.1016/j.ijfoodmicro.2015.08.004}, abstractNote={Lactobacillus buchneri has recently been associated with anaerobic spoilage of fermented cucumbers due to its ability to metabolize lactic acid into acetic acid and 1,2-propanediol. However, we have limited knowledge of other chemical components in fermented cucumber that may be related to spoilage and the unique metabolic capabilities of L. buchneri. Comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry metabolite profiling methods were applied for nontargeted detection of volatile and nonvolatile compounds to determine changes that occurred during anaerobic fermented cucumber spoilage by L. buchneri LA1147 and during reproduction of spoilage with natural microbiota. Univariate analysis of variance combined with hierarchial clustering analysis revealed 92 metabolites that changed during spoilage (P<0.01). Decreases were observed in mono and disaccharides, amino acids, nucleosides, long chain fatty acids, aldehydes, and ketones, and increases were observed in several alcohols and butanoic and pentanoic acids. Most of the metabolite changes preceded lactic acid utilization, indicating that lactic acid is not a preferred substrate for anaerobic spoilage organisms in fermented cucumbers. The ability to detect biochemical changes that preceded lactate utilization revealed citrulline, trehalose, and cellobiose as compounds that may signify metabolic activity of L. buchneri spoilage strains prior to any significant product degradation.}, journal={INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY}, author={Johanningsmeier, Suzanne D. and McFeeters, Roger F.}, year={2015}, month={Dec}, pages={40–48} }
 @article{koskiniemi_truong_mcfeeters_simunovic_2013, title={Effects of Acid, Salt, and Soaking Time on the Dielectric Properties of Acidified Vegetables}, volume={16}, ISSN={["1532-2386"]}, DOI={10.1080/10942912.2011.567428}, abstractNote={In order to design a continuous microwave process for pasteurization of acidified vegetables, equilibration phenomena in acid and salt solutions must be examined with regards to changes in dielectric properties. The objective of this study was to examine the effects of acid and salt concentration on the dielectric properties of acidified vegetables. Broccoli florets and sweet potato cubes (1.2 cm) were blanched to facilitate acid and salt equilibration by heating for 15 s in boiling de-ionized water. Red bell pepper cubes were not blanched. The vegetable samples were then acidified in solutions of 1–2% sodium chloride with 0.5–2% citric acid. Dielectric properties were measured at 915 MHz from 25 to 100°C after 0-, 4-, and 24-h soaking periods in the solutions using an open-ended coaxial probe connected to a network analyzer. Equilibration occurred within 4 h of salting and acidification. Acid and salt concentration had no significant effect on the dielectric constant (ϵ′). However, ϵ′ was significantly different among vegetables (p < 0.05). Dielectric loss factor (ϵ″) was not affected by acid, but significantly increased with salt concentration. These results provide necessary dielectric property information to apply microwave heating technology in processing of acidified vegetables.}, number={4}, journal={INTERNATIONAL JOURNAL OF FOOD PROPERTIES}, author={Koskiniemi, Craig B. and Truong, Van-Den and McFeeters, Roger F. and Simunovic, Josip}, year={2013}, month={May}, pages={917–927} }
 @article{johanningsmeier_mcfeeters_2013, title={Metabolism of lactic acid in fermented cucumbers by Lactobacillus buchneri and related species, potential spoilage organisms in reduced salt fermentations}, volume={35}, ISSN={["1095-9998"]}, DOI={10.1016/j.fm.2013.03.004}, abstractNote={Recent evidence suggests that Lactobacillus buchneri may play an important role in spoilage-associated secondary fermentation of cucumbers. Lactic acid degradation during fermented cucumber spoilage is influenced by sodium chloride (NaCl) concentration, pH, and presence of oxygen. Objectives were to evaluate these factors on lactic acid utilization by L. buchneri, and to compare the biochemical changes to those which occur during fermented cucumber spoilage. Effects of NaCl (0, 2, 4, and 6% w/w), pH (3.8 vs 5.0), and aerobic environment were investigated using fermented cucumber media (FC) inoculated with spoilage microorganisms. At pH 3.8, L. buchneri degraded lactic acid in all NaCl concentrations. The highest rate of lactic acid utilization occurred in FC with 2% NaCl (P < 0.05). Lactic acid utilization was nearly identical under aerobic and anaerobic conditions, indicating that oxygen does not influence lactate metabolism by L. buchneri. Lactic acid utilization was accompanied by increases in acetic acid and 1,2-propanediol, and Lactobacillus rapi was able to convert 1,2-propanediol to propionic acid and propanol. L. buchneri initiated spoilage in a wide range of environmental conditions that may be present in commercial cucumber fermentations, and L. rapi may act syntrophically with L. buchneri to produce the commonly observed spoilage metabolites.}, number={2}, journal={FOOD MICROBIOLOGY}, author={Johanningsmeier, Suzanne D. and McFeeters, Roger F.}, year={2013}, month={Sep}, pages={129–135} }
 @article{koskiniemi_truong_mcfeeters_simunovic_2013, title={Quality evaluation of packaged acidified vegetables subjected to continuous microwave pasteurization}, volume={54}, ISSN={["1096-1127"]}, DOI={10.1016/j.lwt.2013.04.016}, abstractNote={The study evaluated the use of 915 MHz continuous microwave processing with a rotation apparatus for pasteurization of acidified vegetable packages. Broccoli florets, and 1.2 cm cubes of broccoli stems, red bell pepper, and sweetpotato were pre-equilibrated to 1 g/100 g NaCl and 0.38 g/100 mL citric acid, and separately placed in 110 mL cups with a 0.5 g/100 mL citric acid solution. Unsealed packages were placed on a conveyor belt and run through a 915 MHz microwave cavity operating at 3.5 kW (residence time = 4 min). After processing, cups were sealed with a lidding film, and held in insulating molds for 30 min. Infrared thermocouples, fiber optic temperature sensors, and infrared imaging were used to monitor product temperatures. Microbial stability and changes in color and instrumental textural properties were measured over a 60-day storage period at 30 °C. Good retention of color and texture of acidified vegetable pieces was observed after microwave pasteurization. Over storage, textural properties significantly degraded for all vegetables, but the brilliant color of red bell pepper and sweetpotato was relatively retained. Chemical indicators of microbial spoilage were not detected at the end of storage. This study demonstrates a successful continuous microwave pasteurization process for producing shelf-stable acidified vegetable packages.}, number={1}, journal={LWT-FOOD SCIENCE AND TECHNOLOGY}, author={Koskiniemi, Craig B. and Truong, Van-Den and McFeeters, Roger F. and Simunovic, Josip}, year={2013}, month={Nov}, pages={157–164} }
 @article{franco_perez-diaz_johanningsmeier_mcfeeters_2012, title={Characteristics of Spoilage-Associated Secondary Cucumber Fermentation}, volume={78}, ISSN={["1098-5336"]}, DOI={10.1128/aem.06605-11}, abstractNote={ABSTRACT}, number={4}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Franco, Wendy and Perez-Diaz, Ilenys M. and Johanningsmeier, Suzanne D. and McFeeters, Roger F.}, year={2012}, month={Feb}, pages={1273–1284} }
 @article{johanningsmeier_franco_perez-diaz_mcfeeters_2012, title={Influence of Sodium Chloride, pH, and Lactic Acid Bacteria on Anaerobic Lactic Acid Utilization during Fermented Cucumber Spoilage}, volume={77}, ISSN={["1750-3841"]}, DOI={10.1111/j.1750-3841.2012.02780.x}, abstractNote={Abstract:  Cucumbers are preserved commercially by natural fermentations in 5% to 8% sodium chloride (NaCl) brines. Occasionally, fermented cucumbers spoil after the primary fermentation is complete. This spoilage has been characterized by decreases in lactic acid and a rise in brine pH caused by microbial instability. Objectives of this study were to determine the combined effects of NaCl and pH on fermented cucumber spoilage and to determine the ability of lactic acid bacteria (LAB) spoilage isolates to initiate lactic acid degradation in fermented cucumbers. Cucumbers fermented with 0%, 2%, 4%, and 6% NaCl were blended into slurries (FCS) and adjusted to pH 3.2, 3.8, 4.3, and 5.0 prior to centrifugation, sterile‐filtration, and inoculation with spoilage organisms. Organic acids and pH were measured initially and after 3 wk, 2, 6, 12, and 18 mo anaerobic incubation at 25 °C. Anaerobic lactic acid degradation occurred in FCS at pH 3.8, 4.3, and 5.0 regardless of NaCl concentration. At pH 3.2, reduced NaCl concentrations resulted in increased susceptibility to spoilage, indicating that the pH limit for lactic acid utilization in reduced NaCl fermented cucumbers is 3.2 or lower. Over 18 mo incubation, only cucumbers fermented with 6% NaCl to pH 3.2 prevented anaerobic lactic acid degradation by spoilage bacteria. Among several LAB species isolated from fermented cucumber spoilage, Lactobacillus buchneri was unique in its ability to metabolize lactic acid in FCS with concurrent increases in acetic acid and 1,2‐propanediol. Therefore, L. buchneri may be one of multiple organisms that contribute to development of fermented cucumber spoilage.}, number={7}, journal={JOURNAL OF FOOD SCIENCE}, author={Johanningsmeier, Suzanne D. and Franco, Wendy and Perez-Diaz, Ilenys and McFeeters, Roger F.}, year={2012}, month={Jul}, pages={M397–M404} }
 @article{johanningsmeier_mcfeeters_2011, title={Detection of Volatile Spoilage Metabolites in Fermented Cucumbers Using Nontargeted, Comprehensive 2-Dimensional Gas Chromatography-Time-of-Flight Mass Spectrometry (GCxGC-TOFMS)}, volume={76}, ISSN={["1750-3841"]}, DOI={10.1111/j.1750-3841.2010.01918.x}, abstractNote={Abstract:  A nontargeted, comprehensive 2‐dimensional gas chromatography‐time‐of‐flight mass spectrometry (GC×GC‐TOFMS) method was developed for the analysis of fermented cucumber volatiles before and after anaerobic spoilage. Volatile compounds extracted by solid‐phase microextraction were separated on a polyethylene glycol 1st‐dimension column and 14% cyanopropylphenyl 2nd‐dimension column. Among 314 components detected in fermented cucumber brine, 199 had peak areas with coefficients of variation below 30%. Peak identifications established by mass spectral library matching were 92% accurate based on 63 authentic standards. Analysis of variance of analytes’ log peak areas revealed 33 metabolites changed in concentration after spoilage (P < 0.05), including increases in acetic, propanoic, and butyric acids, n‐propyl acetate, several alcohols, and a decrease in furfural. GC×GC‐TOFMS with a nontargeted, semi‐automated approach to data analysis made possible the separation, identification, and determination of differences in polar volatile components, facilitating the discovery of several metabolites related to fermented cucumber spoilage.}, number={1}, journal={JOURNAL OF FOOD SCIENCE}, author={Johanningsmeier, Suzanne D. and McFeeters, Roger F.}, year={2011}, pages={C168–C177} }
 @article{koskiniemi_truong_simunovic_mcfeeters_2011, title={Improvement of heating uniformity in packaged acidified vegetables pasteurized with a 915MHz continuous microwave system}, volume={105}, ISSN={0260-8774}, url={http://dx.doi.org/10.1016/j.jfoodeng.2011.02.019}, DOI={10.1016/j.jfoodeng.2011.02.019}, abstractNote={Continuous microwave processing to produce shelf-stable acidified vegetables with moderate to high salt contents poses challenges in pasteurization due to reduced microwave penetration depths and non-uniform heating. Cups of sweetpotato, red bell pepper, and broccoli acidified to pH 3.8 with citric acid solution containing 0–1% NaCl were placed on a conveyor belt and passed through a microwave tunnel operating at 915 MHz and 4 kW with a 4 min residence time. The time–temperature profiles of vegetable pieces at 5 locations in the package were measured using fiber optic temperature sensors. Addition of 1% NaCl to the cover solution lowered microwave penetration into vegetable pieces and decreased the mean temperature in cups of acidified vegetables from 84 to 73 °C. Soaking blanched vegetables for 24 h in a solution with NaCl and citric acid prior to processing improved microwave heating. Heating was non-uniform in all packages with a cold spot of approximately 60 °C at a point in the container farthest from the incident microwaves. More uniform heating was achieved by implementation of a two-stage rotation apparatus to rotate vegetable cups 180° during processing. Rotating the cups resulted in more uniform heating and a temperature of 77 °C at the cold spot. This is above the industrial standard of 74 °C for in-pack pasteurization of acidified vegetables. The effective treatment involved blanching, soaking for 24 h in a NaCl and citric acid solution, and 180° rotation. This work has contributed to a better understanding of the influence of salt addition and distribution during dielectric heating of acidified vegetables using a 915 MHz continuous microwave system.}, number={1}, journal={Journal of Food Engineering}, publisher={Elsevier BV}, author={Koskiniemi, Craig B. and Truong, Van-Den and Simunovic, Josip and McFeeters, Roger F.}, year={2011}, month={Jul}, pages={149–160} }
 @article{perez-diaz_mcfeeters_2011, title={Preparation of a Lactobacillus Plantarum Starter Culture for Cucumber Fermentations That Can Meet Kosher Guidelines}, volume={76}, ISSN={["0022-1147"]}, DOI={10.1111/j.1750-3841.2010.01981.x}, abstractNote={Abstract:  A method is described for growth of a Lactobacillus plantarum starter culture in jars of commercially available pasteurized fresh‐pack kosher dill cucumbers so that jars can be used to inoculate commercial scale cucumber fermentation tanks. A procedure is also described to transfer lactic acid bacteria from frozen storage in MRS broth into cucumber juice and commercial jars of kosher dill cucumbers so that a selected strain of lactic acid bacteria can be kosher certified for commercial fermentations in processing plants that operate under kosher certification. The strain of L. plantarum used in these experiments grew to maximum cell numbers in 4 d at 20 to 25 °C and then maintained viable cell numbers for 2 wk at >108 CFU/mL so the culture was suitable for inoculation of fermentation tanks. Refrigeration of jars of culture after they grow to maximum numbers minimizes die‐off of cells sufficiently so that a pure culture can be maintained by aseptically transferring brine containing viable bacteria to a new pH‐adjusted jar only once every 4 mo.}, number={2}, journal={JOURNAL OF FOOD SCIENCE}, author={Perez-Diaz, I. M. and McFeeters, R. F.}, year={2011}, month={Mar}, pages={M120–M123} }
 @article{mcfeeters_perez-diaz_2010, title={Fermentation of Cucumbers Brined with Calcium Chloride Instead of Sodium Chloride}, volume={75}, ISSN={["0022-1147"]}, DOI={10.1111/j.1750-3841.2010.01558.x}, abstractNote={ABSTRACT:  Waste water containing high levels of NaCl from cucumber fermentation tank yards is a continuing problem for the pickled vegetable industry. A major reduction in waste salt could be achieved if NaCl were eliminated from the cucumber fermentation process. The objectives of this project were to ferment cucumbers in brine containing CaCl2 as the only salt, to determine the course of fermentation metabolism in the absence of NaCl, and to compare firmness retention of cucumbers fermented in CaCl2 brine during subsequent storage compared to cucumbers fermented in brines containing both NaCl and CaCl2 at concentrations typically used in commercial fermentations. The major metabolite changes during fermentation without NaCl were conversion of sugars in the fresh cucumbers primarily to lactic acid which caused pH to decrease to less than 3.5. This is the same pattern that occurs when cucumbers are fermented with NaCl as the major brining salt. Lactic acid concentration and pH were stable during storage and there was no detectable production of propionic acid or butyric acid that would indicate growth of spoilage bacteria. Firmness retention in cucumbers fermented with 100 to 300 mM CaCl2 during storage at a high temperature (45 °C) was not significantly different from that obtained in fermented cucumbers with 1.03 M NaCl and 40 mM CaCl2. In closed jars, cucumber fermentations with and without NaCl in the fermentation brine were similar both in the chemical changes caused by the fermentative microorganisms and in the retention of firmness in the fermented cucumbers.}, number={3}, journal={JOURNAL OF FOOD SCIENCE}, author={McFeeters, Roger F. and Perez-Diaz, Ilenys}, year={2010}, month={Apr}, pages={C291–C296} }
 @article{perez-diaz_mcfeeters_2010, title={Preservation of Acidified Cucumbers with a Natural Preservative Combination of Fumaric Acid and Allyl Isothiocyanate that Target Lactic Acid Bacteria and Yeasts}, volume={75}, ISSN={["0022-1147"]}, DOI={10.1111/j.1750-3841.2010.01587.x}, abstractNote={ABSTRACT:  Without the addition of preservative compounds cucumbers acidified with 150 mM acetic acid with pH adjusted to 3.5 typically undergo fermentation by lactic acid bacteria. Fumaric acid (20 mM) inhibited growth of Lactobacillus plantarum and the lactic acid bacteria present on fresh cucumbers, but spoilage then occurred due to growth of fermentative yeasts, which produced ethanol in the cucumbers. Allyl isothiocyanate (2 mM) prevented growth of Zygosaccharomyces globiformis, which has been responsible for commercial pickle spoilage, as well as the yeasts that were present on fresh cucumbers. However, allyl isothiocyanate did not prevent growth of Lactobacillus plantarum. When these compounds were added in combination to acidified cucumbers, the cucumbers were successfully preserved as indicated by the fact that neither yeasts or lactic acid bacteria increased in numbers nor were lactic acid or ethanol produced by microorganisms when cucumbers were stored at 30 °C for at least 2 mo. This combination of 2 naturally occurring preservative compounds may serve as an alternative approach to the use of sodium benzoate or sodium metabisulfite for preservation of acidified vegetables without a thermal process.}, number={4}, journal={JOURNAL OF FOOD SCIENCE}, author={Perez-Diaz, I. M. and McFeeters, R. F.}, year={2010}, month={May}, pages={M204–M208} }
 @article{truong_deighton_thompson_mcfeeters_dean_pecota_yencho_2009, title={Characterization of Anthocyanins and Anthocyanidins in Purple-Fleshed Sweetpotatoes by HPLC-DAD/ESI-MS/MS}, volume={58}, ISSN={0021-8561 1520-5118}, url={http://dx.doi.org/10.1021/jf902799a}, DOI={10.1021/jf902799a}, abstractNote={Purple-fleshed sweetpotatoes (PFSP) can be a healthy food choice for consumers and a potential source for natural food colorants. This study aimed to identify anthocyanins and anthocyanidins in PFSP, and to evaluate the effect of thermal processing on these polyphenolic compounds. Freeze-dried powder of raw and steamed samples of three PFSP varieties were extracted with acidified methanol using a Dionex ASE 200 accelerated solvent extractor. Seventeen anthocyanins were identified by HPLC-DAD/ESI-MS/MS for Stokes Purple and NC 415 varieties with five major compounds: cyanidin 3-caffeoylsophoroside-5-glucoside, peonidin 3-caffeoylsophoroside-5-glucoside, cyanidin 3-caffeoyl-p-hydroxybenzoylsophoroside-5-glucoside, peonidin 3-caffeoyl-p-hydroxybenzoyl-sophoroside-5-glucoside, and peonidin-caffeoyl-feruloylsophoroside-5-glucoside. Okinawa variety showed 12 pigments with 3 major peaks identified as cyanidin 3-caffeoylsophoroside-5-glucoside, cyanidin 3-(6'',6'''-dicaffeoylsophoroside)-5-glucoside and cyanidin 3-(6''-caffeoyl-6'''-feruloylsophoroside)-5-glucoside. Steam cooking had no significant effect on total anthocyanin content or the anthocyanin pigments. Cyanidin and peonidin, which were the major anthocyanidins in the acid hydrolyzed extracts, were well separated and quantified by HPLC with external standards. Cyanidin and peonidin, which contribute to the blue and red hues of PFSP, can be simply quantified by HPLC after acid hydrolysis of the anthocyanins.}, number={1}, journal={Journal of Agricultural and Food Chemistry}, publisher={American Chemical Society (ACS)}, author={Truong, Van-Den and Deighton, Nigel and Thompson, Roger T. and McFeeters, Roger F. and Dean, Lisa O. and Pecota, Kenneth V. and Yencho, G. Craig}, year={2009}, month={Dec}, pages={404–410} }
 @article{neta_johanningsmeier_drake_mcfeeters_2009, title={Effects of pH Adjustment and Sodium Ions on Sour Taste Intensity of Organic Acids}, volume={74}, ISSN={["1750-3841"]}, DOI={10.1111/j.1750-3841.2009.01127.x}, abstractNote={ABSTRACT:  Protonated organic acid species have been shown to be the primary stimuli responsible for sour taste of organic acids. However, we have observed that sour taste may be modulated when the pH of acid solutions is raised using sodium hydroxide. Objectives were to evaluate the effect of pH adjustment on sour taste of equimolar protonated organic acid solutions and to investigate the potential roles of organic anions and sodium ions on sour taste perception. Despite equal concentrations of protonated acid species, sour taste intensity decreased significantly with increased pH for acetic, lactic, malic, and citric acids (P < 0.05). Total organic anion concentration did not explain the suppression of sour taste in solutions containing a blend of 3 organic acids with constant concentration of protonated organic acid species and hydrogen ions and variable organic anion concentrations (R2= 0.480, P = 0.12). Sour taste suppression in these solutions seemed to be more closely related to sodium ions added in the form of NaOH (R2= 0.861, P = 0.007). Addition of 20 mM NaCl to acid solutions resulted in significant suppression of sour taste (P = 0.016). However, sour taste did not decrease with further addition of NaCl up to 80 mM. Presence of sodium ions was clearly shown to decrease sour taste of organic acid solutions. Nonetheless, suppression of sour taste in pH adjusted single acid solutions was greater than what would be expected based on the sodium ion concentration alone, indicating an additional suppression mechanism may be involved.}, number={4}, journal={JOURNAL OF FOOD SCIENCE}, author={Neta, E. R. D. and Johanningsmeier, S. D. and Drake, M. A. and McFeeters, R. F.}, year={2009}, month={May}, pages={S165–S169} }
 @article{maruvada_mcfeeters_2009, title={Evaluation of enzymatic and non-enzymatic softening in low salt cucumber fermentations}, volume={44}, ISSN={["1365-2621"]}, DOI={10.1111/j.1365-2621.2009.01925.x}, abstractNote={Summary}, number={6}, journal={INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY}, author={Maruvada, Rashmi and McFeeters, Roger F.}, year={2009}, month={Jun}, pages={1108–1117} }
 @article{perez-diaz_mcfeeters_2009, title={Modification of azo dyes by lactic acid bacteria}, volume={107}, ISSN={["1364-5072"]}, DOI={10.1111/j.1365-2672.2009.04227.x}, abstractNote={Aim:  The ability of Lactobacillus casei and Lactobacillus paracasei to modify the azo dye, tartrazine, was recently documented as the result of the investigation on red coloured spoilage in acidified cucumbers. Fourteen other lactic acid bacteria (LAB) were screened for their capability to modify the food colouring tartrazine and other azo dyes of relevance for the textile industry.}, number={2}, journal={JOURNAL OF APPLIED MICROBIOLOGY}, author={Perez-Diaz, I. M. and McFeeters, R. F.}, year={2009}, month={Aug}, pages={584–589} }
 @article{perez-diaz_truong_webber_mcfeeters_2008, title={Microbial growth and the effects of mild acidification and preservatives in refrigerated sweet potato puree}, volume={71}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028X-71.3.639}, abstractNote={Refrigerated sweet potato puree is a convenient form of sweet potato that can be used as an ingredient in formulated foods. The microbiology of refrigerated sweet potato puree during storage for up to 5 weeks was evaluated. Because the puree was made by comminuting steam-cooked sweet potatoes before refrigeration, no naturally occurring vegetative bacterial cells were detected during a 4-week period of refrigerated storage at 4 degrees C. However, if postprocessing microbial contamination of the puree were to occur, contaminating microorganisms such as Listeria monocytogenes could grow during refrigerated storage. The effects of acidification or the addition of potassium sorbate and sodium benzoate on a population of L. monocytogenes inoculated into refrigerated (4 degrees C) sweet potato puree were determined. Inoculation of the refrigerated puree with L. monocytogenes at 10(6) CFU/ml resulted in a 3-log increase after 3 weeks storage of nonsupplemented puree. Supplementation of the sweet potato puree with 0.06% (wt/vol) sorbic acid or benzoic acid plus mild acidification of the sweet potato puree with citric acid to pH 4.2 prevented growth of L. monocytogenes during storage at 4 degrees C.}, number={3}, journal={JOURNAL OF FOOD PROTECTION}, author={Perez-Diaz, Ilenys M. and Truong, Van-Den and Webber, Ashlee and Mcfeeters, Roger F.}, year={2008}, month={Mar}, pages={639–642} }
 @article{perez-diaz_mcfeeters_2008, title={Microbiological preservation of cucumbers for bulk storage using acetic acid and food preservatives}, volume={73}, ISSN={["1750-3841"]}, DOI={10.1111/j.1750-3841.2008.00795.x}, abstractNote={ABSTRACT:  Microbial growth did not occur when cucumbers were preserved without a thermal process by storage in solutions containing acetic acid, sodium benzoate, and calcium chloride to maintain tissue firmness. The concentrations of acetic acid and sodium benzoate required to ensure preservation were low enough so that stored cucumbers could be converted to the finished product without the need to wash out and discard excess acid or preservative. Since no thermal process was required, this method of preservation would be applicable for storing cucumbers in bulk containers. Acid tolerant pathogens died off in less than 24 h with the pH, acetic acid, and sodium benzoate concentrations required to assure the microbial stability of cucumbers stored at 30 °C. Potassium sorbate as a preservative in this application was not effective. Yeast growth was observed when sulfite was used as a preservative.}, number={6}, journal={JOURNAL OF FOOD SCIENCE}, author={Perez-Diaz, I. M. and McFeeters, R. F.}, year={2008}, month={Aug}, pages={M287–M291} }
 @article{neta_johanningsmeier_drake_mcfeeters_2007, title={A chemical basis for sour taste perception of acid solutions and fresh-pack dill pickles}, volume={72}, ISSN={["1750-3841"]}, DOI={10.1111/j.1750-3841.2007.00400.x}, abstractNote={ABSTRACT:  Sour taste is influenced by pH and acids present in foods. It is not currently possible, however, to accurately predict and modify sour taste intensity in foods containing organic acids. The objective of this study was to investigate the roles of protonated (undissociated) organic acid species and hydrogen ions in evoking sour taste. Sour taste intensity increased linearly with hydrogen ion concentration (R2= 0.995), and with the concentration of protonated organic acid species at pH 3.5 (R2= 0.884), 4.0 (R2= 0.929), and 4.5 (R2= 0.975). The structures of organic acid molecules did not affect sour taste after adjusting for the effects of protonated organic acid species and hydrogen ions. Sour taste intensity was also linearly related to the total concentration of protonated organic acid species in fresh‐pack dill pickles (R2= 0.957). This study showed that the sour taste of organic acids was directly related to the number of molecules with at least 1 protonated carboxyl group plus the hydrogen ions in solution. Conclusions from these results are that all protonated organic acids are equally sour on a molar basis, that all protonated species of a given organic acid are equally sour, and that hydrogen ions and protonated organic acids are approximately equal in sour taste on a molar basis. This study provides a new understanding of the chemical species that are able to elicit sour taste and reveals a basis for predicting sour taste intensity in the formulation of acidified foods.}, number={6}, journal={JOURNAL OF FOOD SCIENCE}, author={Neta, E. R. Da Concetcao and Johanningsmeier, S. D. and Drake, M. A. and McFeeters, R. F.}, year={2007}, month={Aug}, pages={S352–S359} }
 @article{teow_truong_mcfeeters_thompson_pecota_yencho_2007, title={Antioxidant activities, phenolic and beta-carotene contents of sweet potato genotypes with varying flesh colours}, volume={103}, ISSN={["1873-7072"]}, DOI={10.1016/j.foodchem.2006.09.033}, abstractNote={Antioxidant activities (μmol Trolox equivalent (TE)/g fresh weight) of 19 sweet potato genotypes with distinctive flesh colour (white, cream, yellow, orange and purple) were measured by oxygen radical absorbance capacity (ORAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2′-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS). Total phenolics were measured using the Folin–Ciocalteau method, total anthocyanins by the pH-differential method, and β-carotene by HPLC. The total antioxidant activity (hydrophilic + lipophilic ORAC) was highest (27.2 μmol TE/g fresh weight (fw)) for NC415 (purple-fleshed) and lowest (2.72 μmol TE/g fw) for Xushu 18 (white-fleshed). The hydrophilic-ORAC values were significantly correlated with the DPPH (R2 = 0.859) and ABTS (R2 = 0.761) values. However, the lipophilic-ORAC values were poorly correlated with the β-carotene contents (R2 = 0.480). The total phenolic contents (0.011–0.949 mg chlorogenic acid equivalent/g fw) were highly correlated with the hydrophilic-ORAC (R2 = 0.937) and DPPH (R2 = 0.820) values. Therefore, the total phenolic content can serve as a useful indicator for the antioxidant activities of sweet potatoes.}, number={3}, journal={FOOD CHEMISTRY}, publisher={Elsevier BV}, author={Teow, Choong C. and Truong, Van-Den and McFeeters, Roger F. and Thompson, Roger L. and Pecota, Kenneth V. and Yencho, G. Craig}, year={2007}, pages={829–838} }
 @article{breidt_hayes_mcfeeters_2007, title={Determination of 5-log reduction times for food pathogens in acidified cucumbers during storage at 10 and 25 degrees C}, volume={70}, ISSN={["0362-028X"]}, DOI={10.4315/0362-028X-70.11.2638}, abstractNote={Outbreaks of acid-resistant foodborne pathogens in acid foods with pH values below 4.0, including apple cider and orange juice, have raised concerns about the safety of acidified vegetable products. For acidified vegetable products with pH values between 3.3 and 4.6, previous research has demonstrated that thermal treatments are needed to achieve a 5-log reduction in the numbers of Escherichia coli O157:H7, Listeria monocytogenes, or Salmonella enterica. For some acidified vegetable products with a pH of 3.3 or below, heat processing can result in unacceptable product quality. The purpose of this study was to determine the holding times needed to achieve a 5-log reduction in E. coli O157:H7, L. monocytogenes, and S. enterica strains in acidified vegetable products with acetic acid as the primary acidulant, a pH of 3.3 or below, and a minimum equilibrated temperature of 10 degrees C. We found E. coli O157:H7 to be the most acid-resistant microorganism for the conditions tested, with a predicted time to achieve a 5-log reduction in cell numbers at 10 degrees C of 5.7 days, compared with 2.1 days (51 h) for Salmonella or 0.5 days (11.2 h) for Listeria. At 25 degrees C, the E. coli O157:H7 population achieved a 5-log reduction in 1.4 days (34.3 h).}, number={11}, journal={JOURNAL OF FOOD PROTECTION}, author={Breidt, Fred, Jr. and Hayes, Janet and McFeeters, Roger F.}, year={2007}, month={Nov}, pages={2638–2641} }
 @article{johanningsmeier_mcfeeters_fleming_thompson_2007, title={Effects of Leuconostoc mesenteroides starter culture on fermentation of cabbage with reduced salt concentrations}, volume={72}, ISSN={["1750-3841"]}, DOI={10.1111/j.1750-3841.2007.00372.x}, abstractNote={ABSTRACT:  Sauerkraut fermentations rely upon selection of naturally occurring lactic acid bacteria by addition of 2.0% to 2.25% granulated sodium chloride (NaCl) to shredded cabbage. Excess brine generated is a waste product with high levels of organic material (BOD) and nonbiodegradable NaCl. The objective was to determine whether addition of Leuconostoc mesenteroides starter culture to reduced‐salt cabbage fermentations would yield sauerkraut with reproducible and acceptable chemical composition and sensory qualities. Shredded cabbage was salted with 0.5%, 1.0%, or 2.0% NaCl (wt/wt) at 2 starter culture levels, none or L. mesenteroides strain LA 81, ATCC 8293 (106 CFU/g). Fermentation products were quantified by high‐performance liquid chromatography, and pH was measured during the initial stages of fermentation and after 10 mo storage at 18 °C. A trained descriptive sensory panel used category scales to rate the flavor and texture of selected sauerkrauts. A modified Kramer shear test was used to measure firmness. Cabbage fermented with L. mesenteroides consistently resulted in sauerkraut with firm texture and reduced off‐flavors across all salt levels (P < 0.05). Conversely, sauerkraut quality was highly variable, with softening and off‐flavors occurring as salt concentrations were decreased in natural fermentations (P < 0.05). Fermentations were rapid, with a more uniform decline in pH when starter culture was added. L. mesenteroides addition to cabbage fermentations ensured that texture and flavor quality were retained, while allowing 50% NaCl reduction. Application of this technology to commercial sauerkraut production could improve the uniformity of fermentations and substantially reduce generation of nonbiodegradable chloride waste.}, number={5}, journal={JOURNAL OF FOOD SCIENCE}, author={Johanningsmeier, Suzanne and McFeeters, Roger F. and Fleming, Henry P. and Thompson, Roger L.}, year={2007}, pages={M166–M172} }
 @article{perez-diaz_kelling_hale_breidt_mcfeeters_2007, title={Lactobacilli and tartrazine as causative a agents of red-color spoilage in cucumber pickle products}, volume={72}, ISSN={["0022-1147"]}, DOI={10.1111/j.1750-3841.2007.00460.x}, abstractNote={ABSTRACT:  The cucumber pickling industry has sporadically experienced spoilage outbreaks in pickled cucumber products characterized by development of red color on the surface of the fruits. Lactobacillus casei and Lactobacillus paracasei were isolated from 2 outbreaks of this spoilage that occurred about 15 y apart during the last 3 decades. Both organisms were shown to produce this spoilage when inoculated into pickled cucumbers while concomitantly degrading the azo dye tartrazine (FD&C yellow nr 5). This food dye is used as a yellow coloring in the brine cover solutions of commercial pickled cucumber products. The red color does not occur in the absence of tartrazine, nor when turmeric is used as a yellow coloring in the pickles. Addition of sodium benzoate to the brine cover solutions of a pickled cucumber product, more specifically hamburger dill pickles, prevented growth of these lactic acid bacteria and the development of the red spoilage.}, number={7}, journal={JOURNAL OF FOOD SCIENCE}, author={Perez-Diaz, I. M. and Kelling, R. E. and Hale, S. and Breidt, F. and McFeeters, R. F.}, year={2007}, month={Sep}, pages={M240–M245} }
 @article{truong_mcfeeters_thompson_dean_shofran_2007, title={Phenolic acid content and composition in leaves and roots of common commercial sweetpotato (Ipomea batatas L.) cultivars in the United States}, volume={72}, ISSN={["1750-3841"]}, DOI={10.1111/j.1750-3841.2007.00415.x}, abstractNote={ABSTRACT:  Phenolic acids in commercially important sweet potato cultivars grown in the United States were analyzed using reversed‐phase high‐performance liquid chromatography (HPLC). Caffeic acid, chlorogenic acid, 4,5‐di‐O‐caffeoylquinic acid, 3,5‐di‐O‐caffeoylquinic acid, and 3,4‐di‐O‐caffeoylquinic acid were well separated with an isocratic elution in less than 25 min compared to about 120 min for analyzing and re‐equilibrating the column with a gradient method. The isocratic elution order of these caffeoylquinic acid derivatives was confirmed by LC‐MS/MS. Chlorogenic acid was the highest in root tissues, while 3,5‐di‐O‐caffeoylquinic acid and/or 4,5‐di‐O‐caffeoylquinic acid were predominant in the leaves. Steam cooking resulted in statistically nonsignificant increases in the concentration of total phenolics and all the individual phenolic acids identified. Sweetpotato leaves had the highest phenolic acid content followed by the peel, whole root, and flesh tissues. However, there was no significant difference in the total phenolic content and antioxidant activity between purees made from the whole and peeled sweet potatoes.}, number={6}, journal={JOURNAL OF FOOD SCIENCE}, author={Truong, V.-D. and McFeeters, R. F. and Thompson, R. T. and Dean, L. L. and Shofran, B.}, year={2007}, month={Aug}, pages={C343–C349} }
 @misc{neta_johanningsmeier_mcfeeters_2007, title={The chemistry and physiology of sour taste - A review}, volume={72}, ISSN={["1750-3841"]}, DOI={10.1111/j.1750-3841.2007.00282.x}, abstractNote={ABSTRACT:  Sour taste is the key element in the flavor profile of food acidulants. Understanding the chemistry and physiology of sour taste is critical for efficient control of flavor in the formulation of acid and acidified foods. After a brief introduction to the main applications of food acidulants, several chemical parameters associated with sour taste are discussed. Special emphasis is given to hydrogen ions, protonated (undissociated) acid species, titratable acidity, anions, molar concentration, and physical and chemical properties of organic acids. This article also presents an overview of the physiology of sour taste and proposed theories for the transduction mechanisms for sour taste. The physiology of sour taste perception remains controversial and significant diversity exists among species with regard to cellular schemes used for detection of stimuli. The variety of mechanisms proposed, even within individual species, highlights the complexity of elucidating sour taste transduction. However, recent evidence suggests that at least one specific sour taste receptor protein has been identified.}, number={2}, journal={JOURNAL OF FOOD SCIENCE}, author={Neta, Edith Ramos Da Conceicao and Johanningsmeier, Suzanne D. and McFeeters, Roger F.}, year={2007}, month={Mar}, pages={R33–R38} }
 @article{cleary_mcfeeters_2006, title={Effects of oxygen and turmeric on the formation of oxidative aldehydes in fresh-pack dill pickles}, volume={54}, ISSN={["1520-5118"]}, DOI={10.1021/jf052868k}, abstractNote={Hexanal, pentanal, and heptanal were found to be normal components of commercially processed, fresh-pack dill pickles. Hexanal and pentanal were present at concentrations severalfold higher than their odor detection thresholds. These aldehydes were also found in pickles that were packed in the laboratory under anaerobic conditions. Injection of oxygen into pickles prepared in anaerobic conditions resulted in the production of increasing the amounts of hexanal, heptanal, and pentanal. Hexanal, pentanal, (E)-2-hexenal, and heptanal levels were negatively correlated with the addition of turmeric in dill pickles with oxygen injected into the jar, indicating that the curcumin present in turmeric is an effective antioxidant in this product. At commercial coloring levels (250 mg/L), turmeric addition maintained aldehyde levels near the concentrations found in commercial fresh-pack pickles packaged in glass containers when oxygen was added in amounts comparable to that which would enter a plastic container during a 1-year storage period. Therefore, the addition of turmeric appears to be an effective approach to minimize the formation of oxidative off-flavors in pasteurized dill pickles that may result from the oxygen permeability of plastic containers.}, number={9}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Cleary, Katherine and McFeeters, Roger F.}, year={2006}, month={May}, pages={3421–3427} }
 @article{bjornsdottir_breidt_mcfeeters_2006, title={Protective effects of organic acids on survival of Escherichia coli O157 : H7 in acidic environments}, volume={72}, ISSN={["1098-5336"]}, DOI={10.1128/aem.72.1.660-664.2006}, abstractNote={ABSTRACT}, number={1}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Bjornsdottir, K and Breidt, F and McFeeters, RF}, year={2006}, month={Jan}, pages={660–664} }
 @article{dougherty_ramos da conceicao neta_mcfeeters_lubkin_breidt_2006, title={Semi-mechanistic partial buffer approach to modeling pH, the buffer properties, and the distribution of ionic species in complex solutions}, volume={54}, ISSN={["1520-5118"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000239454700045&KeyUID=WOS:000239454700045}, DOI={10.1021/jf0531508}, abstractNote={In many biological science and food processing applications, it is very important to control or modify pH. However, the complex, unknown composition of biological media and foods often limits the utility of purely theoretical approaches to modeling pH and calculating the distributions of ionizable species. This paper provides general formulas and efficient algorithms for predicting the pH, titration, ionic species concentrations, buffer capacity, and ionic strength of buffer solutions containing both defined and undefined components. A flexible, semi-mechanistic, partial buffering (SMPB) approach is presented that uses local polynomial regression to model the buffering influence of complex or undefined components in a solution, while identified components of known concentration are modeled using expressions based on extensions of the standard acid-base theory. The SMPB method is implemented in a freeware package, (pH)Tools, for use with Matlab. We validated the predictive accuracy of these methods by using strong acid titrations of cucumber slurries to predict the amount of a weak acid required to adjust pH to selected target values.}, number={16}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Dougherty, Daniel P. and Ramos Da Conceicao Neta, Edith and McFeeters, Roger F. and Lubkin, Sharon R. and Breidt, Frederick, Jr.}, year={2006}, month={Aug}, pages={6021–6029} }
 @misc{johanningsmeier_mcfeeters_drake_2005, title={A hypothesis for the chemical basis for perception of sour taste}, volume={70}, ISSN={["1750-3841"]}, DOI={10.1111/j.1365-2621.2005.tb07111.x}, abstractNote={Sour taste has been considered the simplest of the basic tastes because it is elicited only by hydrogen ions. However, there is not a sufficiently clear understanding of that relationship to allow sour taste intensity to be predicted and rationally modified in foods. On the basis of analysis of sensory data from our laboratory and reanalysis of previously published data, we propose a new hypothesis for the chemical basis for sour taste perception: The intensity of sour taste perception in acid solutions or acidified foods is linearly related to the molar concentration of all organic acid species with at least 1 protonated carboxyl group plus the molar concentration of free hydrogen ions. This hypothesis implies that, on a molar basis, different organic acids will be equally sour, provided at least 1 carboxyl group is protonated. The major effect of pH on sour taste will be to determine the degree of protonation of organic acids. If this hypothesis is confirmed, it will provide a new understanding of the chemical basis for this basic taste perception and have broad usefulness in the formulation of products in which sour taste is an important component of flavor.}, number={2}, journal={JOURNAL OF FOOD SCIENCE}, author={Johanningsmeier, SD and McFeeters, RF and Drake, M}, year={2005}, month={Mar}, pages={R44–R48} }
 @article{johanningsmeier_fleming_thompson_mcfeeters_2005, title={Chemical and sensory properties of sauerkraut produced with Leuconostoc mesenteroides starter cultures of differing malolactic phenotypes}, volume={70}, ISSN={["1750-3841"]}, DOI={10.1111/j.1365-2621.2005.tb09989.x}, abstractNote={ABSTRACT:  Research was conducted to determine whether Leuconostoc mesenteroides starter cultures with and without malolactic activity (MDC+ and MDC‐, respectively) influenced sensory and chemical properties of sauerkraut. No sensory differences were found between MDC+ and MDC− sauerkraut (P≥ 0.05). In addition, sulfur compound profiles of the resulting sauerkraut were nearly identical. Brining at lower NaCl (0.5%) with either inoculum changed both the microbiology and chemistry of the fermenting sauerkraut, leading to decreased sauerkraut sulfur flavor. Quantification of allyl isothiocyanate (AITC), dimethyl disulfide, dimethyl trisulfide (DMTS), methyl methanethiosulfinate, and methyl methanethiosulfonate (MMTSO2) by gas chromatography‐mass spectrometry showed that sauerkraut sulfur flavor correlated linearly with DMTS and MMTSO2 (P≤ 0.01).}, number={5}, journal={JOURNAL OF FOOD SCIENCE}, author={Johanningsmeier, SD and Fleming, HP and Thompson, RL and McFeeters, RF}, year={2005}, pages={S343–S349} }
 @article{breidt_hayes_osborne_mcfeeters_2005, title={Determination of 5-log pathogen reduction times for heat-processed, acidified vegetable brines}, volume={68}, ISSN={["0362-028X"]}, DOI={10.4315/0362-028X-68.2.305}, abstractNote={Recent outbreaks of acid-resistant food pathogens in acid foods, including apple cider and orange juice, have raised concerns about the safety of acidified vegetable products. We determined pasteurization times and temperatures needed to assure a 5-log reduction in the numbers of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella strains in acidified cucumber pickle brines. Cocktails of five strains of each pathogen were (separately) used for heat-inactivation studies between 50 and 60 degrees C in brines that had an equilibrated pH value of 4.1. Salmonella strains were found to be less heat resistant than E. coli O157:H7 or L. monocytogenes strains. The nonlinear killing curves generated during these studies were modeled using a Weibull function. We found no significant difference in the heat-killing data for E. coli O157:H7 and L. monocytogenes (P = 0.9709). The predicted 5-log reduction times for E. coli O157:H7 and L. monocytogenes were found to fit an exponential decay function. These data were used to estimate minimum pasteurization times and temperatures needed to ensure safe processing of acidified pickle products and show that current industry pasteurization practices offer a significant margin of safety.}, number={2}, journal={JOURNAL OF FOOD PROTECTION}, author={Breidt, F and Hayes, JS and Osborne, JA and McFeeters, RF}, year={2005}, month={Feb}, pages={305–310} }
 @article{passos_felder_fleming_mcfeeters_ollis_2005, title={Dynamic model for mass transfer of solutes in cucumber fermentation}, volume={68}, ISSN={["0260-8774"]}, DOI={10.1016/j.jfoodeng.2004.06.002}, abstractNote={A mathematical model for the mass transfer of solutes between whole cucumbers and brine in cucumber fermentation has been developed that takes into account permeation of solutes through stomata in the cucumber skin and through the epidermal cells in the skin, as well as film diffusion through the surrounding brine boundary layer. The model was used to fit experimental data for the time-dependent concentrations of solutes that permeate into the cucumbers (glucose and malate) and out of them (lactic acid, acetic acid, ethanol, and sodium chloride). The rate of lactic acid transport through the stomata was found to be three orders of magnitude greater than that through the epidermis, and the permeabilities of lactic and acetic acids were effectively independent of the brine circulation rate. These results indicate that the rate of permeation of solutes into and out of cucumbers was controlled by mass transfer through the stomata, with neither film diffusion nor epidermal diffusion having a significant effect. The model differential equation for solute transfer combined with a set of rate equations for microbial growth will provide a good basis to establish a complete mechanistic model for the cucumber fermentation process.}, number={3}, journal={JOURNAL OF FOOD ENGINEERING}, author={Passos, FV and Felder, RM and Fleming, HP and McFeeters, RF and Ollis, DF}, year={2005}, month={Jun}, pages={297–302} }
 @article{mcconnell_truong_walter_mcfeeters_2005, title={Physical, chemical and microbial changes in shredded sweet potatoes}, volume={29}, ISSN={["1745-4549"]}, DOI={10.1111/j.1745-4549.2005.00026.x}, abstractNote={With the increasing demand for freshly cut vegetables, a substantial potential exists in developing minimally processed sweet potato products. This study was undertaken to determine the effects of semipermeable polymeric materials and modified atmosphere packaging (MAP) on quality changes and microbial growth in shredded sweet potatoes under refrigerated storage. Shredded sweet potatoes from two major commercial cultivars (Beauregard and Hernandez) were packed in low and medium O2permeability bags and flushed with gas composed of 5% O2, 4% CO2and 91% N2. Quality changes and microbial growth were monitored in comparison to the samples packed in air using high-O2permeable films. The quality of shredded sweet potatoes could be maintained for 7 days at 4C in air, but extended up to 14 days in MAP. Considering the parameters measured in this investigation, the best results were obtained by MAP using moderately O2-permeable film (7000 cm3/atm/m2/24 h). Shredded sweet potatoes stored in MAP showed less changes in tissue firmness, dry matter, ascorbic acid and starch than shredded sweet potatoes stored in air. The MAP-stored shredded sweet potatoes consistently exhibited fewer total aerobic bacteria and enteric bacteria compared to the shredded sweet potatoes stored in air. Yeasts, molds, lactic acid bacteria, color, beta-carotene and sugars of all stored shredded sweet potatoes did not significantly change, regardless of treatments. Higher ethanol levels were generated in the MAP-stored shredded sweet potatoes after 10 days, but off-odors were not detected in any of the MAP-stored shredded sweet potatoes.}, number={3-4}, journal={JOURNAL OF FOOD PROCESSING AND PRESERVATION}, author={McConnell, R and Truong, VD and Walter, WM and McFeeters, RF}, year={2005}, pages={246–267} }
 @article{mcfeeters_2004, title={Fermentation microorganisms and flavor changes in fermented foods}, volume={69}, DOI={10.1111/j.1365-2621.2004.tb17876.x}, abstractNote={ABSTRACT:  Food fermentation processes often result in profound changes in flavor relative to the starting ingredients. However, fermenting foods are typically very complex ecosystems with active enzyme systems from the ingredient materials interacting with the metabolic activities of the fermentation organisms. Factors such as added salt, particle sizes, temperature, and oxygen levels will also have important effects on the chemistry that occurs during fermentation. This is a brief review of recent research on flavor changes in food fermentations. The emphasis will be on the role of lactic acid bacteria in changing the compounds that help determine the character of fermented foods from plant‐based substrates.}, number={1}, journal={Journal of Food Science}, author={McFeeters, R. F.}, year={2004}, pages={215–217} }
 @article{breidt_hayes_mcfeeters_2004, title={Independent effects of acetic acid and pH on survival of Escherichia coli in simulated acidified pickle products}, volume={67}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028x-67.1.12}, abstractNote={Our objective was to determine the effects of organic acids and pH on the rate at which selected strains of Escherichia coli O157:H7 die in acid solutions representative of acidified pickle products (pH < 4.6). We used gluconic acid/sodium gluconate (pKa = 3.7) as a noninhibitory buffer to maintain pH at selected values in the absence of other organic acids. This was possible because we found that the inhibitory effects of this acid on E. coli strains at pH 3.1 were independent of acid concentration over a range of 2 to 200 mM. By this method, the lethal effects of acetic acid solutions (100 to 400 mM) at selected pH values between 3.1 and 4.1 were compared with the effects of pH alone (as determined using gluconate buffer). We found D-values were two- to fourfold lower with acetic acid compared with the effect of pH alone for simulated pickle brines in this pH range. Glutamic acid, an amino acid that is known to enhance acid resistance in E. coli and is a component of pickle brines, protected the E. coli strains from the specific effects of acetic acid.}, number={1}, journal={JOURNAL OF FOOD PROTECTION}, author={Breidt, F and Hayes, JS and McFeeters, RF}, year={2004}, month={Jan}, pages={12–18} }
 @article{mcfeeters_barrangou_barish_morrison_2004, title={Rapid softening of acidified peppers: Effect of oxygen and sulfite}, volume={52}, DOI={10.1021/jf003459533}, number={14}, journal={Journal of Agricultural and Food Chemistry}, author={McFeeters, R. F. and Barrangou, L. M. and Barish, A. O. and Morrison, S. S.}, year={2004}, pages={4554–4557} }
 @article{passos_fleming_hassan_mcfeeters_2003, title={Effect of malic acid on the growth kinetics of Lactobacillus plantarum}, volume={63}, ISSN={["0175-7598"]}, DOI={10.1007/s00253-003-1375-7}, abstractNote={The fermentation kinetics of Lactobacillus plantarum were studied in a specially designed broth formulated from commercially available, dehydrated components (yeast extract, trypticase, ammonium sulfate) in batch and continuous culture. During batch growth in the absence of malic acid, the specific growth rate was 0.20 h(-1). Malic acid in the medium, at 2 mM or 10 mM, increased the specific growth rate of L. plantarum to 0.34 h(-1). An increase in the maximum cell yield due to malic acid also was observed. Malic acid in the medium (12 mM) reduced the non-growth-associated (maintenance energy) coefficient and increased the biomass yield in continuous culture, based on calculations from the Luedeking and Piret model. The biomass yield coefficient was estimated as 27.4 mg or 34.3 mg cells mmol(-1) hexose in the absence or presence of malic acid, respectively. The maintenance coefficient was estimated as 3.5 mmol or 1.5 mmol hexose mg(-1) cell h(-1) in the absence or presence of malic acid. These results clearly demonstrate the energy-sparing effect of malic acid on the growth- and non-growth-associated energy requirements for L. plantarum. The quantitative energy-sparing effect of malic acid on L. plantarum has heretofore not been reported, to our knowledge.}, number={2}, journal={APPLIED MICROBIOLOGY AND BIOTECHNOLOGY}, author={Passos, FV and Fleming, HP and Hassan, HM and McFeeters, RF}, year={2003}, month={Dec}, pages={207–211} }
 @article{papageorge_mcfeeters_fleming_2003, title={Factors influencing texture retention of salt-free, acidified, red bell peppers during storage}, volume={51}, ISSN={["0021-8561"]}, DOI={10.1021/jf025788e}, abstractNote={Red bell peppers were stored in a salt-free, acidified cover solution with sulfite as a microbial preservative. The texture retention of stored peppers was evaluated as a function of pH, acid, calcium, blanch treatment, and growing conditions of the peppers. Field-grown peppers softened at a faster rate than greenhouse-grown peppers and exhibited more variability in their ability to maintain texture during storage. Improved firmness retention of red peppers stored at 30 degrees C was observed when the pH was adjusted to be in the range of 3.4-3.8, when at least 5 mM calcium was added to the peppers, and when red peppers were blanched at 75 degrees C for at least 1 min.}, number={5}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Papageorge, LM and McFeeters, RF and Fleming, HP}, year={2003}, month={Feb}, pages={1460–1463} }
 @article{walter_truong_simunovic_mcfeeters_2003, title={Low-temperature blanching of sweetpotatoes to improve firmness firmness retention: Effect on compositional and textural properties}, volume={68}, ISSN={["0022-1147"]}, DOI={10.1111/j.1365-2621.2003.tb09633.x}, abstractNote={ABSTRACT:  Low‐temperature blanching of sweetpotatoes (SP) prior to cooking has been shown to significantly increase firmness retention. This research investigated the effect of blanching on firmness, pectin methylesterase activity (PME), pectin methylation, and galacturonic acid and cell wall material concentrations in SP tissue subjected to blanching and cooking treatments. PME activity decreased 82% after 20 min of blanching in water at 62°C, while sample firmness continued to increase with blanching time (3.5 N for unblanched and 19.0 N for 90 min blanched, and cooked tissue), indicating that firming due to pectin demethylation explains part of the observed increased firmness retention caused by low‐temperature blanching, but unknown factors also play a role.,}, number={4}, journal={JOURNAL OF FOOD SCIENCE}, author={Walter, WM and Truong, VD and Simunovic, N and McFeeters, RF}, year={2003}, month={May}, pages={1244–1247} }
 @article{mcfeeters_barish_2003, title={Sulfite analysis of fruits and vegetables by high-performace liquid chromatography (HPLC) with ultraviolet spectrophotometric detection}, volume={51}, ISSN={["1520-5118"]}, DOI={10.1021/jf025693c}, abstractNote={Free and total sulfite were analyzed in acidified vegetable products, instant mashed potatoes, and dried apples. Sulfite was separated by HPLC and quantified with a UV-vis detector. Resolution from components of food samples was achieved by varying the acid concentration of the eluant solution and by appropriate choice of the analytical wavelength. The minimum detectable levels for sulfite were 0.5 mg/L for a 10-cm analytical column and 1.5 mg/L for a 30-cm column. For analyses done with a 30-cm column, the coefficient of variation was <2% for analysis of free sulfite and total sulfite in acidified vegetables. For dried apples and instant potatoes, it ranged from 1 to 6.5%. The corresponding analytical errors were <4% and 1.2-5.6%, respectively, for the 10-cm column.}, number={6}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={McFeeters, RF and Barish, AO}, year={2003}, month={Mar}, pages={1513–1517} }
 @article{lu_fleming_mcfeeters_yoon_2002, title={Effects of anions and cations on sugar utilization in cucumber juice fermentation}, volume={67}, ISSN={["0022-1147"]}, DOI={10.1111/j.1365-2621.2002.tb09469.x}, abstractNote={ABSTRACT:  :}, number={3}, journal={JOURNAL OF FOOD SCIENCE}, author={Lu, Z and Fleming, HP and McFeeters, RF and Yoon, SA}, year={2002}, month={Apr}, pages={1155–1161} }
 @article{lu_fleming_mcfeeters_2002, title={Effects of fruit size on fresh cucumber composition and the chemical and physical consequences of fermentation}, volume={67}, DOI={10.1111/j.1365-2621.2002.tb08841.x}, abstractNote={ABSTRACT:  The composition of pickling cucumbers varied with fruit size, which affected buffer capacity, sugar utilization, terminal pH, and texture of the fermented fruit. We found that as cucumber size increased (from less than 27 to 51 mm in dia), malic acid, pH, buffer capacity, and dry matter content decreased, and glucose and fructose contents increased. Fruit firmness and bloater damage were greater in large than in small, fermented, whole cucumbers. Blanching (75 °C, 30 s) had little effect on the fermentation and prevention of bloater formation in finished products, regardless of fruit sizes. It was demonstrated that cucumber juice can serve as a model system for studying the metabolic, but not the physical (texture, bloater damage), consequences of lactic acid bacteria chosen as starter cultures for cucumber fermentation.}, number={8}, journal={Journal of Food Science}, author={Lu, Z. and Fleming, H. P. and McFeeters, R. F.}, year={2002}, pages={2934–2939} }
 @article{dougherty_breidt_mcfeeters_lubkin_2002, title={Energy-based dynamic model for variable temperature batch fermentation by Lactococcus lactis}, volume={68}, ISSN={["0099-2240"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000175407300048&KeyUID=WOS:000175407300048}, DOI={10.1128/AEM.68.5.2468-2478.2002}, abstractNote={ABSTRACT}, number={5}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Dougherty, DP and Breidt, F and McFeeters, RF and Lubkin, SR}, year={2002}, month={May}, pages={2468–2478} }
 @article{palma-harris_mcfeeters_fleming_2002, title={Fresh cucumber flavor in refrigerated pickles: Comparison of sensory and instrumental analysis}, volume={50}, ISSN={["0021-8561"]}, DOI={10.1021/jf0116404}, abstractNote={The ability of nonacidified, refrigerated pickled cucumbers to produce the fresh cucumber flavor impact compounds (E,Z)-2,6-nonadienal and (E)-2-nonenal declined during storage. Production of these compounds decreased as the pH of refrigerated cucumbers was reduced. Despite the fact that the concentrations of (E,Z)-2,6-nonadienal and (E)-2-nonenal generated were over 10(5)-fold greater than the threshold levels, it was possible for a sensory panel to consistently detect differences in the intensity of fresh cucumber flavor, provided the pH difference between samples was 1 unit or greater. The presence of spices did not interfere with the ability of panelists to detect differences in fresh flavor intensity. There was a linear correlation between sensory scores and the amount of (E,Z)-2,6-nonadienal produced by cucumbers equilibrated at different pH levels.}, number={17}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Palma-Harris, C and McFeeters, RF and Fleming, HP}, year={2002}, month={Aug}, pages={4875–4877} }
 @article{fasina_fleming_mcfeeters_2002, title={Thermal and rheological properties of brine from fermented and sulfite-preserved cucumbers}, volume={25}, ISSN={["0145-8876"]}, DOI={10.1111/j.1745-4530.2002.tb00568.x}, abstractNote={ABSTRACT}, number={4}, journal={JOURNAL OF FOOD PROCESS ENGINEERING}, author={Fasina, OO and Fleming, HP and McFeeters, RF}, year={2002}, month={Oct}, pages={307–322} }
 @article{lu_fleming_mcfeeters_2001, title={Differential glucose and fructose utilization during cucumber juice fermentation}, volume={66}, ISSN={["1750-3841"]}, DOI={10.1111/j.1365-2621.2001.tb15600.x}, abstractNote={ABSTRACT:  Glucose (32 mM) and fructose (36mM) of cucumber juice were degraded simultaneously by Lactobacillus plantarum, but at different rates and extents. Glucose depletion was slightly more rapid than fructose during the exponential growth phase, but slower thereafter and stopped before exhaustion. In contrast, fructose degradation continued until all naturally present fructose was exhausted. When cucumber juice was supplemented with fructose and/or glucose, the starter culture continued to ferment fructose, but not glucose, resulting in an increase in lactic acid production and a decrease in terminal pH. Fructose utilization was not affected by the presence of glucose, but the presence of fructose reduced glucose utilization.}, number={1}, journal={JOURNAL OF FOOD SCIENCE}, author={Lu, Z and Fleming, HP and McFeeters, RF}, year={2001}, pages={162–166} }
 @article{unal_fleming_mcfeeters_thompson_breidt_giesbrecht_2001, title={Novel quantitative assays for estimating the antimicrobial activity of fresh garlic juice}, volume={64}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028X-64.2.189}, abstractNote={Novel agar diffusion and broth dilution assays were developed for quantitatively estimating the antimicrobial activity of fresh garlic juice. Bacteria found to be inhibited by garlic juice in agar diffusion assay included two gram-positive and five gram-negative species. Leuconostoc mesenteroides was not inhibited. Escherichia coli B-103 (HB101, with pJH101, ampicillin resistant, 100 microg ml(-1)) was inhibited and chosen as the standard culture for quantitative assays. The agar diffusion assay was based on the slope ratio method, where the slope of dose response for garlic juice was divided by the slope of dose response for methylmethane thiosulfonate (MMTSO2). Juice from fresh garlic varied in activity between 1.76 and 2.31 microg of MMTSO2 per mg of garlic juice. The activity of juice decreased during 11 months of storage of garlic cloves at 5 degrees C from 2.31 to less than 0.1 microg of MMTSO2 per mg of juice. The broth dilution assay also used the E. coli B-103 culture, which permitted selective enumeration of this bacterium when 100 microg ml(-1) of ampicillin was incorporated into the enumerating agar. Selective enumeration was essential since the garlic juice was not sterile and, thus, contained natural flora. Growth of E. coli was unaffected by 0.1%, delayed by 0.25%, and completely inhibited at 0.5 and 2% garlic juice in broth during 24 h of incubation at 37 micro C. The minimum inhibition concentration of garlic juice by broth dilution assay was, thus, estimated to be 0.5%, which is equivalent to 3.46 microg of MMTSO2 per mg of garlic juice by the agar diffusion assay.}, number={2}, journal={JOURNAL OF FOOD PROTECTION}, author={Unal, R and Fleming, HP and McFeeters, RF and Thompson, RL and Breidt, F and Giesbrecht, FG}, year={2001}, month={Feb}, pages={189–194} }
 @article{palma-harris_mcfeeters_fleming_2001, title={Solid-phase microextraction (SPME) technique for measurement of generation of fresh cucumber flavor compounds}, volume={49}, ISSN={["0021-8561"]}, DOI={10.1021/jf010182w}, abstractNote={Investigations were carried out to determine whether flavor compounds characteristic for fresh cucumbers could be rapidly determined using a solid-phase microextraction (SPME) dynamic headspace sampling method combined with gas chromatography and flame ionization detection. Cucumbers were sampled, during blending, for fresh cucumber flavor compounds (E,Z)-2,6-nonadienal and (E)-2-nonenal. The GC was such that the two target compounds were separated and baseline-resolved. Relative standard deviations for analysis of both (E,Z)-2,6-nonadienal and (E)-2-nonenal using this SPME sampling method were +/-10%. Utility of the analytical method was demonstrated by determining the effect of heat treatments on the ability of cucumbers to produce these flavor impact compounds.}, number={9}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Palma-Harris, C and McFeeters, RF and Fleming, HP}, year={2001}, month={Sep}, pages={4203–4207} }
 @article{zhou_mcfeeters_fleming_2000, title={Development of oxidized odor and volatile aldehydes in fermented cucumber tissue exposed to oxygen}, volume={48}, ISSN={["0021-8561"]}, DOI={10.1021/jf990287n}, abstractNote={Changes in volatile compounds in fermented cucumber tissue during exposure to oxygen were investigated by purge and trap sampling, followed by GC-MS. Hexanal and a series of trans unsaturated aldehydes, (E)-2-pentenal, (E)-2-hexenal, (E)-2-heptenal, and (E)-2-octenal, increased in fermented cucumber slurries exposed to oxygen. Sensory evaluation of oxidized odor was correlated with the increase in aldehyde concentrations. Other identified volatile components present after fermentation did not show major changes during exposure to oxygen. There was no decrease in the formation of aldehydes in fermented cucumber samples that were heated to inactivate enzymes before exposure to oxygen. These results indicated that the formation of aldehydes in oxygen was due to nonenzymatic reactions.}, number={2}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Zhou, A and McFeeters, RF and Fleming, HP}, year={2000}, month={Feb}, pages={193–197} }
 @article{zhou_mcfeeters_fleming_2000, title={Inhibition of formation of oxidative volatile components in fermented cucumbers by ascorbic acid and turmeric}, volume={48}, ISSN={["0021-8561"]}, DOI={10.1021/jf990669t}, abstractNote={Two naturally occurring antioxidants, ascorbic acid and turmeric, were effective in inhibiting formation of hexanal, (E)-2-penenal, (E)-2-hexenal, (E)-2-heptenal, and (E)-2-octenal when slurries of fermented cucumber tissue were exposed to oxygen. Added ascorbic acid prevented formation of most of these oxidative aldehydes at 175 ppm or greater. Turmeric, which is used commercially as a yellow coloring in cucumber pickle products, was found to almost completely prevent aldehyde formation at 40 ppm.}, number={10}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Zhou, A and McFeeters, RF and Fleming, HP}, year={2000}, month={Oct}, pages={4910–4912} }
 @article{pattee_isleib_giesbrecht_mcfeeters_2000, title={Investigations into genotypic variations of peanut carbohydrates}, volume={48}, ISSN={["0021-8561"]}, DOI={10.1021/jf9910739}, abstractNote={Carbohydrates are known to be important precursors in the development of roasted peanut quality. However, little is known about their genotypic variation. A better understanding of the role of carbohydrates in roasted peanut quality requires first an understanding of the genotypic variation in the soluble carbohydrate components. Ion exchange chromatography was used to isolate 20 different carbohydrate components in 52 genotypes grown in replicated trials at two locations. Inositol, glucose, fructose, sucrose, raffinose, and stachyose were quantitated, and 12 unknown peaks were evaluated on the basis of the peak height of the unknown relative to the cellobiose internal standard peak height. Peaks tentatively identified as verbascose and ajugose could not be properly integrated because of tailing. Of the 18 carbohydrates that were estimated, 9 exhibited significant variation between test environments, 5 among market types, 14 among genotypes within market types, and 11 exhibited some significant form of genotype x environment interaction. Genotypes accounted for 38-78% of the total variation for the known components, suggesting that broad-sense heritability for these components is high. The observed high genotypic variation in carbohydrate components is similar to the high genotypic variation observed for the sweetness attribute in roasted peanuts, which raises the question regarding possible interrelationships. The establishment of such interrelationships could be most beneficial to peanut breeding programs to ensure the maintenance of flavor quality in future peanut varieties.}, number={3}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Pattee, HE and Isleib, TG and Giesbrecht, FG and McFeeters, RF}, year={2000}, month={Mar}, pages={750–756} }
 @article{pattee_isleib_giesbrecht_mcfeeters_2000, title={Relationships of sweet, bitter, and roasted peanut sensory attributes with carbohydrate components in peanuts}, volume={48}, ISSN={["0021-8561"]}, DOI={10.1021/jf9910741}, abstractNote={Certain roasted peanut quality sensory attributes have been shown to be heritable. Currently the only means of measuring these traits is the use of a trained sensory panel. This is a costly and time-consuming process. It is desirable, from a cost, time, and sample size perspective, to find other methodologies for estimating these traits. Because sweetness is the most heritable trait and it has a significant positive relationship to the roasted peanut trait, the possible relationships between heritable sensory traits and 18 carbohydrate components (inositol, glucose, fructose, sucrose, raffinose, stachyose, and 12 unknown peaks) in raw peanuts from 52 genotypes have been investigated. Previously reported correlations among sweet, bitter, and roasted peanut attributes were evident in this study as well. Where there was positive correlation of total sugars with sweetness, there also was positive correlation of total sugars with roasted peanut attribute and negative correlation of total sugars with bitterness and astringency. The expected generalized relationship of total sugars or sucrose to sweetness could not be established because the relationship was not the same across all market-types. Further work is needed to determine the nature of the chemical components related to the bitter principle, which appear to modify the sweet response and interfere with the sensory perception of sweetness, particularly in the Virginia market-type. Also, certain carbohydrate components showed significant relationships with sensory attributes in one market-type and not another. These differential associations demonstrate the complexity of the interrelationships among sweet, bitter, and roasted peanut sensory attributes. Within two market-types it is possible to improve the efficiency of selection for sweetness and roasted peanut quality by assaying for total carbohydrates. On the basis of the regression values the greatest efficiency would occur in the fastigiate market-type and then the runner.}, number={3}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Pattee, HE and Isleib, TG and Giesbrecht, FG and McFeeters, RF}, year={2000}, month={Mar}, pages={757–763} }
 @article{gheyas_blankenship_young_mcfeeters_1998, title={Dietary fibre composition in developing apple fruits}, volume={73}, ISSN={["0022-1589"]}, DOI={10.1080/14620316.1998.11511026}, abstractNote={SummaryChanges in dietary fibre composition of ‘Delicious’, ‘Golden Delicious’, and ‘Stayman’ apples were studied over the course of fruit development. Fruit were analysed every 15 d starting 30 d after full bloom (DAFB) up to 150 DAFB in ‘Delicious’, 135 DAFB in ‘Golden Delicious’, and 120 DAFB in ‘Stayman’. Nonstarch cell wall materials (NSCWM) and nonstarch polysaccharides (NSP) content of apple flesh of all the cultivars decreased during development. During the period between 30 DAFB and 120 DAFB, NSP content of ‘Delicious’, ‘Golden Delicious’, and ‘Stayman’ fruit decreased by 25.2%, 29.0%, and 19.3%, respectively. Relative amount of monosaccharides present in apple fibre also changed during development. Proportions of rhamnose, arabinose, mannose, and galactose decreased during development while the proportions of xylose, glucose and uronic acid increased. Firmness of apple flesh was positively correlated with its NSP content. Firmness was also strongly correlated with the amounts of galactose, gluco...}, number={5}, journal={JOURNAL OF HORTICULTURAL SCIENCE & BIOTECHNOLOGY}, author={Gheyas, F and Blankenship, SM and Young, E and McFeeters, R}, year={1998}, month={Sep}, pages={631–639} }
 @article{krall_mcfeeters_1998, title={Pectin hydrolysis: Effect of temperature, degree of methylation, pH, and calcium on hydrolysis rates}, volume={46}, ISSN={["0021-8561"]}, DOI={10.1021/jf970473y}, abstractNote={The rate of acid hydrolysis of pectin at pH 3 decreased as the degree of pectin methylation (DM) increased. Acid hydrolysis rates for polypectate (<5% DM) declined as the pH was raised from 2 to 6. Pectin (35% and 70% DM) hydrolyzed more slowly than polypectate below pH 3.5, but degradation rates then increased because β-elimination became the dominant reaction above pH 3.8. Temperature effects on the hydrolysis rates at pH 3 of pectin samples from different sources, as indicated by values for the entropy and enthalpy of activation for this reaction, were very different from the effect of temperature on cucumber tissue softening at the same pH. The results indicated that pectin hydrolysis is not the primary reaction responsible for nonenzymatic plant tissue softening at acid pH. Though calcium ions strongly inhibit plant tissue softening at acid pH, calcium ions did not inhibit acid hydrolysis of pectin. Keywords: Plants; cell wall; pectic substances; degradation; Cucumis sativus}, number={4}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Krall, SM and McFeeters, RF}, year={1998}, month={Apr}, pages={1311–1315} }
 @article{mcfeeters_1998, title={Use and removal of sulfite by conversion to sulfate in the preservation of salt-free cucumbers}, volume={61}, ISSN={["0362-028X"]}, DOI={10.4315/0362-028X-61.7.885}, abstractNote={Cucumbers (Cucumis sativus) were microbiologically stable in cover liquid containing 300 ppm of added sodium metabisulfite (calculated as SO2), 20 mM calcium chloride, and HCl to give an equilibrated pH of 3.5. The sulfur(IV) oxoanions could be easily removed to nondetectable levels (< 3 ppm) by addition of an equimolar amount of hydrogen peroxide, which rapidly converted S(IV) primarily to sulfate ions. When sulfur(IV) oxoanions were removed from stored fresh cucumbers, 85% of the added metabisulfite could be accounted for by formation of sulfate ions. If cucumbers were heated before addition and removal of sulfur(IV) oxoanions, 96% of that added was converted to sulfate by hydrogen peroxide. Preservation of cucumbers in this way does not require fermentation, so addition of salt is not needed to select for lactic acid bacteria.}, number={7}, journal={JOURNAL OF FOOD PROTECTION}, author={McFeeters, RF}, year={1998}, month={Jul}, pages={885–890} }
 @article{zhou_mcfeeters_1998, title={Volatile compounds in cucumbers fermented in low-salt conditions}, volume={46}, ISSN={["0021-8561"]}, DOI={10.1021/jf9704726}, abstractNote={Volatile compounds present in cucumbers fermented in 2% salt were analyzed using purge and trap concentration followed by GC-MS. Thirty-seven volatile compounds were identified from over 100 peaks detected using GC-MS. Most of the identified compounds did not change during fermentation. However, the ability of disrupted cucumber tissue to produce (E,Z)-2,6-nonadienal and 2-nonenal, the two most important volatiles in fresh cucumber odor, decreased during fermentation. In addition, linalool increased to levels several times its odor threshold during the first 10 days of fermentation. Keywords: Cucumis sativus; gas chromatography; mass spectrometry; Lactobacillus plantarum; Cucurbitaceae}, number={6}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Zhou, AC and McFeeters, RF}, year={1998}, month={Jun}, pages={2117–2122} }
 @article{gheyas_blankenship_young_mcfeeters_1997, title={Dietary fibre content of thirteen apple cultivars}, volume={75}, ISSN={["0022-5142"]}, DOI={10.1002/(SICI)1097-0010(199711)75:3<333::AID-JSFA883>3.0.CO;2-R}, abstractNote={Fibre composition of the following 13 apple cultivars was studied: 'Cortland', 'Empire', 'Fuji', 'Golden Delicious', 'Gala', 'Granny Smith', 'Jonagold', 'Mutsu', 'McIntosh', 'Delicious', 'Rome', 'Stayman' and 'York'. Fruit samples from each of these cultivars were analysed for non-starch cell wall materials (NSCWM) and non-starch polysaccharides (NSP). NSCWM was further fractionated into soluble and insoluble fibre fractions. Both NSCWM and NSP content were found to be significantly influenced by cultivar. NSCWM content ranged from 19.1 g kg -1 apple flesh in 'Fuji' to 36.2 g kg -1 in 'York'. Mean (± SD) NSCWM content of all the cultivars was 23.1 ± 45 g kg -1 . NSP content of apple flesh ranged from 13.8 g kg -1 in 'McIntosh' to 287 g kg -1 in 'York' with the overall mean for all cultivars being 17.9 ± 4.2 g kg -1 . Relative amount of monosaccharides found in the hydrolysates of apple fibre also varied among cultivars. The greatest difference was observed in galactose content.}, number={3}, journal={JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE}, author={Gheyas, F and Blankenship, SM and Young, E and McFeeters, R}, year={1997}, month={Nov}, pages={333–340} }
 @misc{daeschel_mcfeeters_fleming_klaenhammer_sanozky_1987, title={Lactic acid bacteria which do not decarboxylate malic acid and fermentation therewith}, volume={4,666,849}, number={1987 May 19}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Daeschel, M. A. and McFeeters, R. F. and Fleming, H. P and Klaenhammer, T. R. and Sanozky, R. B.}, year={1987} }
 @article{mcfeeters_fleming_thompson_1982, title={MALIC AND CITRIC ACIDS IN PICKLING CUCUMBERS}, volume={47}, ISSN={["0022-1147"]}, DOI={10.1111/j.1365-2621.1982.tb12899.x}, abstractNote={ABSTRACT}, number={6}, journal={JOURNAL OF FOOD SCIENCE}, author={MCFEETERS, RF and FLEMING, HP and THOMPSON, RL}, year={1982}, pages={1859-&} }