Determinação de adulteração por adição de leite bovino em queijo bubalino

Abstract

Buffalo milk has a high nutritional value and is an excellent element for the preparation of dairy products, has higher levels of fat, protein, total solids and some minerals, compared to bovine milk. However, fluctuations in the availability of milk from species other than cattle, and the higher price compared to bovine milk, give rise to the incentive for adulteration of traditional cheeses. The fraudulent addition of bovine milk in cheese made with buffalo milk will lead to nutritional and economic loss to the consumer. In our country, legislation currently no reported technique for this function, therefore, a need exists to develop a practical and reliable determination of such tampering. Thus, the study aimed to optimize and validate the test method for determination of beta-carotene as a way to determine adulteration in mozzarella made with buffalo milk, since, according to the literature, physiological differences Buffalo for bovine animals cause a greater conversion of carotenoids from feeding fodder to retinol, which would lead to staining of the white buffalo derivatives of origin, due to the almost complete of carotenoids in their constitution. Analyses were carried out at EMBRAPA Food Technology in the laboratory of High Performance Liquid Chromatography (HPLC) using samples prepared only with buffalo milk and / or mixed with cow milk for identification and quantification of beta-carotene, as a marker of authenticity, and quantification of retinol in these derivatives at 60 days and 200 days after birth, assessing whether the lactation period and fat could influence the results. To ensure reliability of the results of the analyzes were performed validation parameters according to the guidance recommended by ANVISA and INMETRO than verification of the efficiency test method using commercial samples of cheese. The results of the validation to the test methods showed that the methods were selective, sensitive and linear for the analysis of beta-carotene and retinal. Indicated no significant difference (p <0.05) in the amounts of retinol, beta-carotene and fat in cheese and milk, respectively, measured in periods of lactation, so no direct influence on the test method, and according with the results of verification of the efficiency the method proved reliable and efficient for the determination of adulteration of cheese made with buffalo milk in the region of Rio de Janeiro.