Accelerated ripening of Ras cheese with a commercial proteinase and intracellular enzymes from Lactobaciilus delbrueckii subsp bulgaricus, Propionibacterium freudenreichii and Brevibacterium linens

Intracellular cell-free enzyme extract of Lactobacillus delbrueckii subsp bulgaricus, Propionibacterium freudenreichii and Brevibacterium linens, was used to accelerate Ras cheese ripening with a commercial proteinase Neutrase. The general gross composition of the cheese was very similar during the ripening period. Significant increase in the free fatty acids of the cheese manufactured with the cell-free extract of Lactobacillus delbrueckii subsp bulgaricus was observed; protein breakdown showing little difference between the control and the treated cheese. After storage, the cheese treated with either Neutrase alone or with cell-free extract had significantly more intense typical Ras cheese flavour, but the presence of Neutrase and cell-free extract gave more bitterness at the end of ripening.