Effect of Tulsi Leaf Extract on Physico-chemical and Microbial Quality of Raw Milk

A study was conducted to assess the effect of tulsi leaf extract on physicochemical and microbial quality of raw milk. Raw milk collected hygienically from an organized dairy farm was assessed by addition of aqueous extracts of tulsi leaves at different concentrations viz., 0.25, 0.5, 0.75 and 1 per cent and studied for physico-chemical and microbial parameters at regular intervals at 37 °C. It was found that addition of aqueous extract of tulsi leaves extracts at 0.5 per cent (v/v) extended the shelf life of raw milk by 5 hours by clot on boiling test. There was a controlled increase in pH and titratable acidity in the milk samples added with 0.5%, 0.75% and 1% level of tulsi leaves extract. The Statistical analysis of data revealed that standard plate count of the aqueous extract of tulsi leaves treated raw milk showed highly significant difference (P ≤0.01) was noticed within treatments during the storage as well as between treatments from 3 to 12 hours of storage.