The effect of adjunct cultures on some chemical and biochemical properties of white-brined cheese

Abstract

The influence of different adjunct cultures on some of the chemical and biochemical properties of white-brined cheese was investigated. Four batches of cheese were produced: C, with no added adjuncts, containing only cheese culture (Lactococcus lactis ssp. lactis plus Lc. lactis ssp. cremoris); CY, containing C culture plus yogurt. culture (Streptococcus thermophilus + Lb. delbrueckii ssp. bulgaricus); CH, containing C culture plus Lactobacillus helveticus; and CYH, containing all of them. Analyses were carried out on days 2, 30, 60 and 90 of ripening. It was found that the addition of different adjunct starters to the cheese influenced (P < 0.01) the chemical composition significantly, except salt contents (P > 0.05). Total solids, protein, fat and pH values were higher in C cheese than the others. On the other hand, titratable acidity of C and CY cheeses was lower than that of CH and CYH cheeses. Although the lipolysis (acid degree value), water-soluble nitrogen (WSN) and trichloroacetic acid-soluble nitrogen (TCA-SN) values of cheeses were affected significantly (P < 0.01) from these treatments, no significant differences exist (P > 0.05) among phosphotungstic acid-soluble nitrogen values. Cheeses made with CYH culture had the highest lipolysis, WSN and TCA-SN. Degradation rates of alpha(sl)- and beta-casein were higher in CYH cheese followed by CY CH and C cheeses. Also, breakdown products of casein were higher in CY, CH and CYH cheeses compared with the control cheese. The amounts of alpha(sl)- and beta-caseins of all cheese samples decreased continuously during the ripening period, while the amounts of alpha(sl)-I casein and other breakdown products increased.