COMPARATIVE STUDY OF YOGHURT PREPARED BY USING LOCAL ISOLATED AND COMMERCIAL IMPORTED STARTER CULTURE

Abstract

The present study was designed to evaluate the local isolated starter culture for the preparation of yoghurt. The yoghurt prepared from this starter culture was compared for various chemical and sensory characteristics with yoghurt prepared from commercial imported starter culture. Locally isolated starter culture and commercial imported culture of Lactobacillus bulgaricus and Streptococcus thermophilus in combination of 1:1 with dose levels of 1.50, 2.00, 2.50 and 3.00 %), were used for the preparation of yoghurt. These yoghurt samples were stored for 15 days in refrigeration and tested for chemical and sensory characteristics. Acidity of the both type of yoghurt samples was significantly affected by storage period and concentration of starter culture. Total solids decreased gradually during the storage in both types of sample. Lactose content of the samples manifested a decreasing trend but fat % did not change during storage. Yoghurt samples prepared from local isolated culture were found equally good as compared with yoghurts prepared from commercial imported starter cultures for their sensory attributes. Mix culture of Lactobacillus bulgaricus and Streptococcus thermophilus may be prepared and used for yoghurt production in 1:1 ratio at the rate of 2.00-2.50 %.