Rastreamento de microrganismos psicrotróficos em etapas de ordenha e quantificação de caseínomacropeptídeo em leite cru

Abstract

The growing demand of milk to supply the population has promoted the evolution of this chain, especially with regard to aspects related to food safety. Thus, this study traced psychrotrophic and proteolytic microorganisms, which are responsible for the separation of the main milk protein, k-casein, with emphasis on identifying and preserving Pseudomonas and Pseudomonas aeruginosa. This species presents high virulence, thus, it is very important to public health and to produce biofilm on several surfaces. The tracing samples were collected from the milking phases and were collected with hand swabs on udder, bucket, cooler, blower, raw milk collection and of milking water. The nonparametric Kruskal-Wallis analysis was used to screening of microorganisms in milking phases, while CMP evaluation results were obtained by the Principal Component Analysis. The results indicated that as the psychrotrophic bacteria counting increased (p <0.05), CMP values decreased. This has indicated lower levels of proteolysis, and it could possibly be related to the fact that psychrotrophic microorganisms present in samples did not have the proteolytic ability. The highest point of contamination indicated in tracing was the surface of the animals udder due to the adopted management, since most producers did not carry out a correct hygiene during this phase