Abstract

The quality of dairy milk depends heavily on microbial contamination and enzyme active measures. Research analysis examined the yeast and mold counts along with Aerobic Plate count (APC) and enzyme activities, including alkaline phosphatase and phosphatase, using 525 pasteurized, 560 raw, and 645 sterilized milk samples. Research measured pH levels and counts of Aerobic Bacillus (AB) and the concentration of Volatile Fatty Acids (VFA). Results indicated that 10.20% of raw milk and 2.45% of pasteurized milk samples exceeded the threshold for APC count. Yeast and mold counts were significantly higher in raw milk (8.56%) compared to pasteurized (5.65%) and sterilized milk (9.30%). AB abundance was highest in raw milk (6.32%) and lowest in sterilized milk (5.65%). Alkaline phosphatase activity (ALP) levels exceeded the critical threshold in raw milk, pasteurized milk and sterilized milk samples. Raw milk had pH of 6.90, slightly higher than pasteurized milk (6.78) but similar to sterilized milk (6.88). VFA concentrations were higher in raw milk (0.40 mM) than in pasteurized (0.28 mM) and sterilized milk (0.35 mM), indicating greater microbial metabolic activity in raw samples. These findings highlight the microbial and enzymatic variations across different milk processing methods, emphasizing need for effective thermal treatments to ensure milk safety. Research established that Bacillus microbes linked positively to ALP measurements in raw milk samples, while pasteurized milk activity levels were related negatively to microbial populations. The analysis demonstrates that dairy milk assessment depends heavily on microbial counts combined with enzymatic activity as well as quality measure indicators.