Effect of 5 years long-term frozen storage on sensory quality of Monterey Jack caprine milk cheese

摘要

A study was conducted to evaluate the effect of 5 years long-term extended frozen-storage on sensory quality of Monterey Jack semi-hard goat milk cheeses stored at 20 C. Three lots of Monterey Jack caprine milk cheeses were manufactured at the university dairy processing plant. Each lot of cheese was placed in 2' x 4' x 1.5' (W x L x H) plastic pouches, vacuum packaged and immediately frozen at -20 degrees C for 5 years. A trained sensory panel (n = 7, 6 females, 1 male) evaluated the cheeses using a previously published lexicon for cheese flavor adapted for evaluating goat milk cheeses. Flavor and taste intensities were scaled using a 15-point intensity scale using the Spectrum (TM) descriptive analysis method. Flavor scores of the fresh cheese as the reference standard were compared with those of the 5 years frozen-stored samples. The results of sensory profiling by the trained panel showed that cooked/milk, sweet and milk fat flavors were significantly (P < 0.05) reduced after the long-term frozen storage, while no changes occurred in diacetyl, whey, sour, salty, brothy and waxy flavors. A noticeable grainy/pasty texture was detected in the 5 years frozen-stored cheeses. However, flavor characteristics of the goat cheeses were not greatly changed suggesting that long-term frozen storage of goat milk cheese appeared to be feasible and applicable for later consumption and marketing