Author : Tatit K. Bunasor

Summary : The study is primarily aimed to investigate the possibility of modifying the conventional method of preparing yoghurt by partially or totally replacing milk protein with the less expensive soymilk protein. Yoghurt-type products were prepared from cow's milk and soymilk in different percentages using lactobacillus bulgaricus and Streptococcus thermophilus separately and in combination. Chemical and physical analyses were performed on the raw materials and the products. Statistical analysis indicated that the addition of soymilk decreased significantly the total solid values for all 3 types of cultures. it also reduced the fat content of the products except for yoghurt treated with S. thermophilus (dry basis). However, as more soymilk was added, the protein values of the products increased significantly for all 3 types of cultures (dry basis). The addition of soymilk decreased titratable acidity of the products in all cultures used. From the different analyses performed in this study, it can be concluded that the best product that can be developed from soymilk-based yoghurt-type product is yoghurt made from 40% soymilk blended with 60% cow's milk and treated with mixed culture.