No abstract

The relationship among consumer acceptability, descriptive sensory attributes, and shelf-life was determined for 2% milk pasteurized at 77, 79, 82, and 85 degrees C. Sensory descriptive attributes and volatile compound composition were monitored over the shelf-life of the products to determine if treatments could be differentiated at various times through out the shelf-life of the product. Consumers preferred 79 degrees C milk over other treatments on d 0; however, at d 6 postpasteurization, 79 and 82 degrees C milks were preferred over the 77 degrees C treatment. Consumers were grouped into 8 clusters based on product liking for both d 0 and d 6 evaluations. The largest cluster liked all pasteurization treatments, and 79 degrees C milk was highly acceptable to all consumers who liked milk. Similar sensory descriptors indicated the end of shelf-life for all pasteurization treatments even though treatments could be differentiated by descriptors on d 0. This research reveals that altering the pasteurization temperature from 79 degrees C may cause a decrease in consumer acceptability to some consumers. Also, altering pasteurization temperature did not affect shelf-life or sensory descriptors and volatile compound composition at the end of shelf-life.

Ten trained panelists determined that 61 characteristics explained the flavor, aroma, texture, basic taste(s), feeling factors and appearance attributes inherent in 12 commercially produced yogurts formulated from bovine milk. When 12 yogurts were used to validate the sensory lexicon, differences (P < 0.05) existed in 37 of the original 61 characteristics. Yogurt brands were then differentiated based on these sensory attributes utilizing principal components analysis. This analysis revealed which attributes were most important in both explaining plain yogurt as well as allowed the clustering of different brands into groups based on taste, aroma, appearance and/or texture. Taste and texture characteristics were more effective at differentiating yogurt treatments than aroma and appearance. Even though taste and texture characteristics allowed trained panelists to identify, differentiate and categorize products, the yogurt could not be differentiated or categorized by fat percentage or source of milk (organic versus conventional). PRACTICAL APPLICATIONS A sensory lexicon was developed that is effective in the characterization and differentiation of nonflavored yogurts. Flavor and texture attributes were effective at differentiating yogurts, but yogurt products could not be grouped together according to sensory descriptors based on fat percentage and milk source (organic versus conventional).

The relationship between the consumer acceptability of Cheddar cheese and its descriptive sensory attributes was determined using preference mapping and logistic regression for three Cheddar cheeses. A trained panel (n = 9) differentiated the cheeses based on taste, aroma and textural attributes. The overall order of consumer preference (P < 0.05) for the three cheeses was 9, 7 and 12 months of aging time, respectively. The trained panel characterized the 7‐ and 9‐month‐old cheeses as having young/undeveloped flavors such as “cooked,”“buttery” and “creamy” flavors, and had volatiles that were responsible for the creamy flavor in cheeses. The 12‐month‐old cheese was characterized by aged/developed flavors and included volatile compounds responsible for fruity aromas and sulfurous, earthy and free fatty acid flavors. External preference mapping revealed six clusters of consumers with varying Cheddar cheese preferences; 74, 95 and 61% of the consumers found 7‐, 9‐ and 12‐month‐old cheeses to be acceptable, respectively.