Laboratory Manual for Common Milk Quality Testing

Milk quality assessment is critical to ensure safety and prevent adulteration in dairy supply chains. This study outlines rapid, cost-effective methods for evaluating milk quality at collection points, including sensory inspection, heat-induced solidification or clot on boiling (C.O.B), Alcohol Coagulation, Lacto scan, Milk Density, Freezing Point, Inhibitor, Phosphatase, and tests for adulterants like cane sugar, urea, formalin, starch, and soaps/detergents. Organoleptic tests rely on sensory evaluation to detect abnormal smell, taste, or appearance, indicating issues like bacterial contamination or acidification (pH < 6.4). The C.O.B. and Alcohol Coagulation tests identify high acidity (pH < 5.8) or protein instability, signaling unsuitable milk for processing. The Alcohol-Alizarin test provides dual insights into protein stability and pH via color changes. Lacto scan offers precise compositional analysis, measuring fat, solids-not-fat (SNF), proteins, and more. Density and freezing point tests detect water adulteration, while inhibitor and phosphatase tests ensure safety by identifying antibiotics or inadequate pasteurization. Adulterant-specific tests reveal cane sugar, urea, formalin, starch, or detergents, safeguarding consumer health. These methods, requiring minimal equipment, enable rapid quality control, ensuring only safe, high-quality milk enters the supply chain. Generally, enhancing test sensitivity to identify lower levels of adulterants and incorporating automated systems for real-time monitoring could be the main goals of future developments.