Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Nutrition, Dietetics, and Food Sciences

Committee Chair(s)

C.A. Ernstrom


C.A. Ernstrom


R. Brown


C. Batty


Three different methods of acidifying skim milk(milk starter, whey base starter and direct acid set) for making cottage cheese were evaluated for their effect on yield, quality and acidification cost. Cultured cottage cheese was produced with milk starter and pH controlled whey-base starter by the short set method. Five percent milk starter and 2.4% whey base starter were approximately equivalent in activity and gave average setting times of 234 to 255 minutes. Direct acid set cottage cheese was made by the Vitex/American method. The setting time required for direct acid set cottage cheese was 158 minutes. Yields of cottage cheese made by direct acid set were significantly higher than with the two cultured methods. Mean yield for direct acid set was 16.1%, the milk starter yield was 14.5% and the whey base method gave a yield of 14.8%.

Protein in the milk starter was less efficiently recovered in the cottage cheese curd than the protein in pasteurized milk.

The direct acid set method produced cottage cheese curd that was more mealy than the curd produced by cultured methods, but was still equal in over-all quality to curd made by milk starter methods. The cottage cheese produced by the different acidification methods were judged superior to commercially made direct acid and commercial cultured cottage cheese by an panel of trained judges. Cottage cheese made by whey base starter was preferred over all of the other cottage cheese. Acidification costs per kilogram of cottage cheese curd were $0.54 for milk starter, $0.019 for whey base starter and $0.114 for direct acid set curd. Overall ingredient cost per 1,000 Kg of skim milk set were $160.04, $154,43 and $170.17 respectively. Saving in time with direct acid set methods probably offset the additional cost of ingredients.