The specialized book "Verification of Adulteration in Milk Sold in Assis/SP" examines the quality of pasteurized dairy products in the city of Assis, São Paulo. In a comprehensive study, 25 milk samples were analyzed over a period of five months to identify possible adulterations and fraud cases. The tests conducted included, among others, digital cryoscopy, density determination, pH value, fat content, acidity in °Dornic, and the lactose sedimentation test. The results were compared with the legal requirements in Brazil, particularly Instruction Normative No. 51. The study found that only 12% of the tested samples met all legal requirements, with significant deviations noted especially in the lactose sedimentation and cryoscopy tests. These results highlight the need for improved quality control in milk production in Assis.