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

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′ × 4′ × 1.5′ (W × L × H) plastic pouches, vacuum packaged and immediately frozen at −20 °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™ 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.