Physical and chemical quality of raw milk commercialized in the sertão region of Paraíba, Brazil

Abstract

In this work, the qualitative profile of raw milk commercialised in the city of Patos-PB was evaluated through physical - chemical and fraud detection analyses. Twenty samples of raw milk sold in 17 districts of the city were collected. The samples were subjected to density determination, cryoscopy index, fat content, titratable acidity, alkaline phosphatase and peroxidase, total dry extract (TDE) and defatted dry extract (DDE), in addition to determining the presence of fraudulent substances such as hydrogen peroxide, formaldehyde, alkaline, starch and urine. According to the research, non-standard samples were verified for the following analyses: density 14/20 (30%) cryoscopy 15/20 (75%), titratable acidity 6/20 (30%), TDE 1/20 (5%) and DDE 7/20 (35%). The fat content showed values accordingly and the alkaline phosphatase and peroxidase tests indicated that the milk did not undergo heat treatment. Furthermore, fraud was verified by adding water 15/20 (75%), presence of alkaline 1/20 (5%) and hydrogen peroxide 1/20 (5%). Most samples of the raw milk 16/20 (80%) showed irregularities, thus attesting that the raw milk commercialized in the municipality is unfit for human consumption. The high index of samples in disagreement with the legislative standards serves as a warning for the risks associated to the consumption of raw milk to the health of its consumers and it represents the failures of the producers to meet quality control standards in the region, as well as, failure from the legal authorities to inspect these producers.