Using proteinase negative variants of Streptococcus cremoris UC310 or UC320 to manufacture cottage cheese, theoretical yields were increased 1 .97% and 1 .56% respectively when compared to the theoretical yields of the proteinase positive parents. Yield differences were strain dependant and differences between positive and negative variants were not manifest with strains of UC73 and UC97. It was necessary to produce bulk culture using pH control and to add sufficient nitrogenous stimulant to provide carry-over stimulant into the cheese milk. All cultures examined developed normally even when the bulk medium contained a blend of 5% yeast extract and casein hydrolysate. It was possible to use the culture to complete the required acidification after direct acidification to pH 5.2 with phosphoric acid. Careful selection of lactic