PRODUCTION, CHARACTERISATION AND VALUE ADDITION OF DAHI MADE FROM RAW, PASTEURIZED AND DOUBLE PASTEURIZED MILK

Abstract

Dahi is an Indian fermented milk product having high nutritive values produced by bacterial fermentation of milk. The main objective of this study is to retain the nutritive value of milk supposedly lost during pasteurization and to compare the anti pathogenic effect of bacterial fermentation and prolonged incubation of dahi from raw milk as cheese from raw milk is approved by FDA regulations provided the ripening is done for a minimum period of 60 days. Further study was undertaken for characterization of the product as dahi based on acidity, acceptability and the microbial count including Lactobacillus and Coliform. Value addition with different herbs and spices was carried out with the intent of observing their two fold effect on dahi as a flavouring agent and their anti Coliform activity. Moreover the anti Coliform activity of these herbs is likely to decrease the drastic thermal processing required to reduce the pathogen count. The setting conditions was optimized at 15hrs of incubation time,37 o C temperature and with an inoculum volume of 5%. The factors involved were acidity, overall acceptability and total microbial count based on the interactive effect of time-temperature profile and inoculum volume. Further scope of study may include standardization of the process of inclusion of herbs and spices based on its nutritive, flavouring and anti-microbial properties.