@article{grasso_grove_halik_arritt_keller_2015, title={Cleaning and sanitation of Salmonella-contaminated peanut butter processing equipment}, volume={46}, ISSN={["1095-9998"]}, DOI={10.1016/j.fm.2014.03.003}, abstractNote={Microbial contamination of peanut butter by Salmonella poses a significant health risk as Salmonella may remain viable throughout the product shelf life. Effective cleaning and sanitation of processing lines are essential for preventing cross-contamination. The objective of this study was to evaluate the efficacy of a cleaning and sanitation procedure involving hot oil and 60% isopropanol, ± quaternary ammonium compounds, to decontaminate pilot-scale processing equipment harboring Salmonella. Peanut butter inoculated with a cocktail of four Salmonella serovars (∼7 log CFU/g) was used to contaminate the equipment (∼75 L). The system was then emptied of peanut butter and treated with hot oil (90 °C) for 2 h followed by sanitizer for 1 h. Microbial analysis of food-contact surfaces (7 locations), peanut butter, and oil were conducted. Oil contained ∼3.2 log CFU/mL on both trypticase soy agar with yeast extract (TSAYE) and xylose lysine deoxycholate (XLD), indicating hot oil alone was not sufficient to inactivate Salmonella. Environmental sampling found 0.25–1.12 log CFU/cm2 remaining on processing equipment. After the isopropanol sanitation (±quaternary ammonium compounds), no Salmonella was detected in environmental samples on XLD (<0.16 log CFU/cm2). These data suggest that a two-step hot oil clean and isopropanol sanitization treatment may eliminate pathogenic Salmonella from contaminated equipment.}, journal={FOOD MICROBIOLOGY}, author={Grasso, Elizabeth M. and Grove, Stephen F. and Halik, Lindsay A. and Arritt, Fletcher and Keller, Susanne E.}, year={2015}, month={Apr}, pages={100–106} }
 @article{cheng_arritt_stevenson_2015, title={Controlling Listeria monocytogenes in Cold Smoked Salmon with the Antimicrobial Peptide Salmine}, volume={80}, ISSN={["1750-3841"]}, DOI={10.1111/1750-3841.12886}, abstractNote={AbstractListeria monocytogenes (LM) is a major safety concern for smoked salmon producers, as it can survive both the brining and smoking process in cold smoked salmon production. Salmine is a cationic antimicrobial peptide derived from the milt of salmon that has been shown to inhibit the growth of LM in vitro. Commercialization of this peptide would add value to a waste product produced when raising salmon. The purpose of this study was to determine the anti‐listeria activity of salmine in smoked salmon by measuring the viable counts of LM over time. Cold smoked salmon was treated with a salmine solution or coated with agar or k‐carrageenan films incorporating salmine to maintain a high surface concentration of the antimicrobial. Samples were then inoculated with approximately 1.0 × 103 cells of LM. The viable counts were then enumerated throughout 4 wk at 4 °C storage. It was found that 5 mg/g salmine delayed the growth of LM on smoked salmon. These samples had significantly (P < 0.05) lower LM counts than on the untreated samples on days 13 and 22. Edible films did not significantly (P > 0.05) improve the antimicrobial efficacy of salmine. The peptide combined with biopolymers also had lower antimicrobial activity in vitro when compared to salmine alone. These results suggest there is potential for salmine to be used as a natural hurdle to inhibit growth of LM due to post process contamination; however, future investigations for extending this effect throughout the shelf life of smoked salmon products are warranted.}, number={6}, journal={JOURNAL OF FOOD SCIENCE}, author={Cheng, Christopher and Arritt, Fletcher and Stevenson, Clinton}, year={2015}, month={Jun}, pages={M1314–M1318} }
 @article{yang_meng_breidt_dean_arritt_2015, title={Effects of Acetic Acid and Arginine on pH Elevation and Growth of Bacillus licheniformis in an Acidified Cucumber Juice Medium}, volume={78}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028x.jfp-14-478}, abstractNote={Bacillus licheniformis has been shown to cause pH elevation in tomato products having an initial pH below 4.6 and metabiotic effects that can lead to the growth of pathogenic bacteria. Because of this, the organism poses a potential risk to acidified vegetable products; however, little is known about the growth and metabolism of this organism in these products. To clarify the mechanisms of pH change and growth of B. licheniformis in vegetable broth under acidic conditions, a cucumber juice medium representative of a noninhibitory vegetable broth was used to monitor changes in pH, cell growth, and catabolism of sugars and amino acids. For initial pH values between pH 4.1 to 6.0, pH changes resulted from both fermentation of sugar (lowering pH) and ammonia production (raising pH). An initial pH elevation occurred, with starting pH values of pH 4.1 to 4.9 under both aerobic and anaerobic conditions, and was apparently mediated by the arginine deiminase reaction of B. licheniformis. This initial pH elevation was prevented if 5 mM or greater acetic acid was present in the brine at the same pH. In laboratory media, under favorable conditions for growth, data indicated that growth of the organism was inhibited at pH 4.6 with protonated acetic acid concentrations of 10 to 20 mM, corresponding to 25 to 50 mM total acetic acid; however, growth inhibition required greater than 300 mM citric acid (10-fold excess of the amount in processed tomato products) products under similar conditions. The data indicate that growth and pH increase by B. licheniformis may be inhibited by the acetic acid present in most commercial acidified vegetable products but not by the citric acid in many tomato products.}, number={4}, journal={JOURNAL OF FOOD PROTECTION}, author={Yang, Zhenquan and Meng, Xia and Breidt, Frederick, Jr. and Dean, Lisa L. and Arritt, Fletcher M.}, year={2015}, month={Apr}, pages={728–737} }
 @article{breidt_kay_cook_osborne_ingham_arritt_2013, title={Determination of 5-Log Reduction Times for Escherichia coli O157:H7, Salmonella enterica, or Listeria monocytogenes in Acidified Foods with pH 3.5 or 3.8}, volume={76}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028x.jfp-12-528}, abstractNote={A critical factor in ensuring the safety of acidified foods is the establishment of a thermal process that assures the destruction of acid-resistant vegetative pathogenic and spoilage bacteria. For acidified foods such as dressings and mayonnaises with pH values of 3.5 or higher, the high water phase acidity (acetic acid of 1.5 to 2.5% or higher) can contribute to lethality, but there is a lack of data showing how the use of common ingredients such as acetic acid and preservatives, alone or in combination, can result in a 5-log reduction for strains of Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes in the absence of a postpackaging pasteurization step. In this study, we determined the times needed at 10° C to achieve a 5-log reduction of E. coli O157:H7, S. enterica, and L. monocytogenes in pickling brines with a variety of acetic and benzoic acid combinations at pH 3.5 and 3.8. Evaluation of 15 different acid-pH combinations confirmed that strains of E. coli O157:H7 were significantly more acid resistant than strains of S. enterica and L. monocytogenes. Among the acid conditions tested, holding times of 4 days or less could achieve a 5-log reduction for vegetative pathogens at pH 3.5 with 2.5% acetic acid or at pH 3.8 with 2.5% acetic acid containing 0.1% benzoic acid. These data indicate the efficacy of benzoic acid for reducing the time necessary to achieve a 5-log reduction in target pathogens and may be useful for supporting process filings and the determination of critical controls for the manufacture of acidified foods.}, number={7}, journal={JOURNAL OF FOOD PROTECTION}, author={Breidt, F., Jr. and Kay, K. and Cook, J. and Osborne, J. and Ingham, B. and Arritt, F.}, year={2013}, month={Jul}, pages={1245–1249} }