@article{croissant_watson_drake_2011, title={Application of Sensory and Instrumental Volatile Analyses to Dairy Products}, volume={2}, ISBN={["978-0-8243-4902-8"]}, ISSN={["1941-1421"]}, DOI={10.1146/annurev-food-022510-133653}, abstractNote={ Comprehensive food flavor analysis requires a multidisciplinary approach. This article presents a comprehensive review of the relationship between sensory and instrumental analysis in the research of food flavor. Common practices for aroma flavor compound isolation, separation, and identification are discussed with strengths and weaknesses of the respective methodologies. A review of whey protein flavor research is presented to demonstrate the range of techniques available for the investigation of food flavors. These techniques are applicable to all food categories. The complexity introduced by food texture regarding flavor analysis is discussed using the attribute creaminess as an example. }, journal={ANNUAL REVIEW OF FOOD SCIENCE AND TECHNOLOGY, VOL 2}, author={Croissant, A. E. and Watson, D. M. and Drake, M. A.}, year={2011}, pages={395–421} }
 @article{croissant_kang_campbell_bastian_drake_2009, title={The effect of bleaching agent on the flavor of liquid whey and whey protein concentrate}, volume={92}, ISSN={["1525-3198"]}, DOI={10.3168/jds.2009-2535}, abstractNote={The increasing use and demand for whey protein as an ingredient requires a bland-tasting, neutral-colored final product. The bleaching of colored Cheddar whey is necessary to achieve this goal. Currently, hydrogen peroxide (HP) and benzoyl peroxide (BPO) are utilized for bleaching liquid whey before spray drying. There is no current information on the effect of the bleaching process on the flavor of spray-dried whey protein concentrate (WPC). The objective of this study was to characterize the effect of bleaching on the flavor of liquid and spray-dried Cheddar whey. Cheddar cheeses colored with water-soluble annatto were manufactured in duplicate. Four bleaching treatments (HP, 250 and 500 mg/kg and BPO, 10 and 20 mg/kg) were applied to liquid whey for 1.5 h at 60 degrees C followed by cooling to 5 degrees C. A control whey with no bleach was also evaluated. Flavor of the liquid wheys was evaluated by sensory and instrumental volatile analysis. One HP treatment and one BPO treatment were subsequently selected and incorporated into liquid whey along with an unbleached control that was processed into spray-dried WPC. These trials were conducted in triplicate. The WPC were evaluated by sensory and instrumental analyses as well as color and proximate analyses. The HP-bleached liquid whey and WPC contained higher concentrations of oxidation reaction products, including the compounds heptanal, hexanal, octanal, and nonanal, compared with unbleached or BPO-bleached liquid whey or WPC. The HP products were higher in overall oxidation products compared with BPO samples. The HP liquid whey and WPC were higher in fatty and cardboard flavors compared with the control or BPO samples. Hunter CIE Lab color values (L*, a*, b*) of WPC powders were distinct on all 3 color scale parameters, with HP-bleached WPC having the highest L* values. Hydrogen peroxide resulted in a whiter WPC and higher off-flavor intensities; however, there was no difference in norbixin recovery between HP and BPO. These results indicate that the bleaching of liquid whey may affect the flavor of WPC and that the type of bleaching agent used may affect WPC flavor.}, number={12}, journal={JOURNAL OF DAIRY SCIENCE}, author={Croissant, A. E. and Kang, E. J. and Campbell, R. E. and Bastian, E. and Drake, M. A.}, year={2009}, month={Dec}, pages={5917–5927} }
 @article{croissant_washburn_dean_drake_2007, title={Chemical properties and consumer perception of fluid milk from conventional and pasture-based production systems}, volume={90}, ISSN={["1525-3198"]}, DOI={10.3168/jds.2007-0456}, abstractNote={The continued popularity of organic and natural foods has generated interest in organic milk, and use of pasture for dairy cattle is a requirement for organic production. This process may improve the health benefits of fluid milk via increases in the unsaturated fatty acid content, including conjugated linoleic acid. Because pasture-based (PB) systems vary in types of forage, it is important to understand the impact of feed on the composition and flavor of fluid milk. The objectives of this study were to compare the chemical and sensory properties of PB milk with conventional fluid milk from Jersey and Holstein cows and to evaluate consumer acceptance of those milks. Fluid milk was collected throughout the 2006 growing season from Holstein and Jersey cows located in 2 herds: one fed a PB diet and one fed a conventional total mixed ration (TMR) diet. Milk was batch-pasteurized and homogenized. Sensory analyses, descriptive profiling, difference testing, and consumer testing were conducted on pasteurized products in separate sessions. Instrumental volatile analysis and fatty acid composition profiling were also conducted. The instrumental and sensory analyses differentiated the PB and TMR milks. Greater percentages of unsaturated fatty acids, including 2 common isomers of conjugated linoleic acid, were measured in PB milks. Trained panelists documented greater intensities of grassy and cowy/barny flavors in PB milks compared with TMR milks when evaluated at 15 degrees C. Volatile compound analysis by solid-phase microextraction and gas chromatography-mass spectrometry separated PB and TMR milk samples. However, analyses showed no compounds unique to either sample. All identified compounds were common to both samples. Consumers were unable to consistently differentiate between PB and TMR milks when evaluated at 7 degrees C, and cow diet had no effect on overall consumer acceptance. These results indicate distinct flavor and compositional differences between TMR and PB milks, but the differences were such that they did not affect consumer acceptance. The current findings are useful to consider as interest in PB dairy production systems grows.}, number={11}, journal={JOURNAL OF DAIRY SCIENCE}, author={Croissant, A. E. and Washburn, S. P. and Dean, L. L. and Drake, M. A.}, year={2007}, month={Nov}, pages={4942–4953} }
 @article{whetstine_croissant_drake_2005, title={Characterization of dried whey protein concentrate and isolate flavor}, volume={88}, ISSN={["1525-3198"]}, DOI={10.3168/jds.S0022-0302(05)73068-X}, abstractNote={The flavor of whey protein concentrates (WPC 80) and whey protein isolates (WPI) was studied using instrumental and sensory techniques. Four WPC 80 and 4 WPI, less than 3 mo old, were collected in duplicate from 6 manufacturers in the United States. Samples were rehydrated and evaluated in duplicate by descriptive sensory analysis. Duplicate samples with internal standards were extracted with diethyl ether. Extracts were then distilled to remove nonvolatile material using high vacuum distillation. Volatile extracts were analyzed using gas chromatography/olfactometry with post peak intensity analysis and aroma extract dilution analysis. Compounds were identified by comparison of retention indices, odor properties, and gas chromatography/mass spectrometry against reference standards. Whey proteins exhibited sweet aromatic, cardboard/wet paper, animal/wet dog, soapy, brothy, cucumber, and cooked/milky flavors, along with the basic taste bitter, and the feeling factor astringency. Key volatile flavor compounds in WPC 80 and WPI were butanoic acid (cheesy), 2-acetyl-1-pyrroline (popcorn), 2-methyl-3-furanthiol (brothy/burnt), 2,5-dimethyl-4-hydroxy-3-(2H)-furanone (maple/spicy), 2-nonenal (fatty/old books), (E,Z)-2,6-nonadienal (cucumber), and (E,Z)-2,4-decadienal (fatty/oxidized). This baseline data on flavor and flavor sources in whey proteins will aid ongoing and future research and will help to identify the most appropriate whey ingredients to use to control or minimize flavor variability in whey enhanced products.}, number={11}, journal={JOURNAL OF DAIRY SCIENCE}, author={Whetstine, MEC and Croissant, AE and Drake, MA}, year={2005}, month={Nov}, pages={3826–3839} }