Effect of pasteurization and lactic acid bacteria on physicochemical, microbiological and sensorial characteristics of costeño cheese

Abstract

The effect of pasteurization and starter cultures on physicochemical, microbiological and sensorial characteristics of costeño cheese was determined. A completely randomized design was conducted, three treatments (T) and three replicates: Treatment 1 (T1): cheese manufactured with pasteurized milk without starter cultures, Treatment 2 (T2): cheese manufactured with pasteurized milk with Lactococcus lactis and Lactococcus cremoris (1:1) and treatment 3 (T3): cheese manufactured with pasteurized milk with Lactococcus lactis, Lactococcus cremoris and Streptococcus thermophillus (0.5:0.5:1). Treatments were compared to a control sample that was prepared with raw milk without starter cultures. Concentration of 1.5% (v/v) of culture was used in relation to the amount of used milk in each treatment. Moisture content was higher in all treatments compared to the control and protein and fat content were significantly lower. Acidity was significantly higher in samples from T2 y T3 compared to T1 and control, due to the metabolism of starter cultures. Total coliforms, yeast and mold counts showed a significant reduction due to pasteurization process in all treatments. Regarding sensorial analysis, hedonic test showed a greater preference in cheese manufactured with T2 (P0.05). There were no significant preferences between T1, T3 and control. Additionally, yield was significantly higher with T1 (22%) and T3 (23%) compared to control.