@article{krause_miracle_sanders_dean_drake_2008, title={The effect of refrigerated and frozen storage on butter flavor and texture}, volume={91}, ISSN={["1525-3198"]}, DOI={10.3168/jds.2007-0717}, abstractNote={Butter is often stored for extended periods of time; therefore, it is important for manufacturers to know the refrigerated and frozen shelf life. The objectives of this study were to characterize the effect of refrigerated and frozen storage on the sensory and physical characteristics of butter. Fresh butter was obtained on 2 occasions from 2 facilities in 113-g sticks and 4-kg bulk blocks (2 facilities, 2 package forms). Butters were placed into both frozen (-20 degrees C) and refrigerated storage (5 degrees C). Frozen butters were sampled after 0, 6, 12, 15, and 24 mo; refrigerated butters were sampled after 0, 3, 6, 9, 12, 15, and 18 mo. Every 3 mo, oxidative stability index (OSI) and descriptive sensory analysis (texture, flavor, and color) were conducted. Every 6 mo, peroxide value (PV), free fatty acid value (FFV), fatty acid profiling, vane, instrumental color, and oil turbidity were examined. A mixed-model ANOVA was conducted to characterize the effects of storage time, temperature, and package type. Storage time, temperature, and package type affected butter flavor, OSI, PV, and FFV. Refrigerated butter quarters exhibited refrigerator/stale off-flavors concurrent with increased levels of oxidation (lower oxidative stability and higher PV and FFV) within 6 mo of refrigerated storage, and similar trends were observed for refrigerated bulk butter after 9 mo. Off-flavors were not evident in frozen butters until 12 or 18 mo for quarters and bulk butters, respectively. Off-flavors in frozen butters were not correlated with instrumental oxidation measurements. Because butter is such a desirable fat source in terms of flavor and textural properties, it is important that manufacturers understand how long their product can be stored before negative attributes develop.}, number={2}, journal={JOURNAL OF DAIRY SCIENCE}, author={Krause, A. J. and Miracle, R. E. and Sanders, T. H. and Dean, L. L. and Drake, M. A.}, year={2008}, month={Feb}, pages={455–465} }
 @article{lozano_miracle_krause_drake_cadwallader_2007, title={Effect of cold storage and packaging material on the major aroma components of sweet cream butter}, volume={55}, ISSN={["0021-8561"]}, DOI={10.1021/jf071075q}, abstractNote={The major aroma compounds of commercial sweet cream AA butter quarters were analyzed by GC-olfactometry and GC-MS combined with dynamic headspace analysis (DHA) and solvent-assisted flavor evaporation (SAFE). In addition, the effect of long-term storage (0, 6, and 12 months) and type of wrapping material (wax parchment paper vs foil) on the aroma components and sensory properties of these butters kept under refrigerated (4 degrees C) and frozen (-20 degrees C) storage was evaluated. The most intense compounds in the aroma of pasteurized AA butter were butanoic acid, delta-octalactone, delta-decalactone, 1-octen-3-one, 2-acetyl-1-pyrroline, dimethyl trisulfide, and diacetyl. The intensities of lipid oxidation volatiles and methyl ketones increased as a function of storage time. Refrigerated storage caused greater flavor deterioration compared with frozen storage. The intensity and relative abundance of styrene increased as a function of time of storage at refrigeration temperature. Butter kept frozen for 12 months exhibited lower styrene levels and a flavor profile more similar to that of fresh butter compared to butter refrigerated for 12 months. Foil wrapping material performed better than wax parchment paper in preventing styrene migration into butter and in minimizing the formation of lipid oxidation and hydroxyl acid products that contribute to the loss of fresh butter flavor.}, number={19}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Lozano, Patricio R. and Miracle, Evan R. and Krause, Andrea J. and Drake, Maryanne and Cadwallader, Keith R.}, year={2007}, month={Sep}, pages={7840–7846} }
 @article{krause_lopetcharat_drake_2007, title={Identification of the characteristics that drive consumer liking of butter}, volume={90}, ISSN={["1525-3198"]}, DOI={10.3168/jds.2006-823}, abstractNote={This study identified and explored the sensory characteristics that drive consumer liking of butter. A trained descriptive panel evaluated 27 commercial butters using a defined sensory language. Two focus groups were conducted with butter consumers to gain an understanding of consumer use and consumption habits. Six representative butters and 2 vegetable oil spreads were selected for consumer acceptance testing. Both internal and external preference mapping techniques were applied to interpret consumer data. Key discriminating sensory characteristics of butters included color intensity; diacetyl, cooked, grassy, and milk fat flavors; and salty taste. From focus groups and quantitative consumer testing, the key butter features were a desirable flavor and a natural image. Negative aspects included price and cholesterol. Five consumer clusters with distinct butter and spread flavor likes and dislikes were identified. Butter is a desirable product to consumers. Sensory expectations of butter vary among consumers, and butters with specific sensory characteristics could be marketed to specific target market segments.}, number={5}, journal={JOURNAL OF DAIRY SCIENCE}, author={Krause, A. J. and Lopetcharat, K. and Drake, M. A.}, year={2007}, month={May}, pages={2091–2102} }