Quality of milk used in informal artisanal production of coalho and butter cheeses

Abstract

Artisanal cheeses such as coalho and butter participate in the socio-cultural identity of people and deserve recognition. Like many artisanal cheeses, it is common to produce coalho and butter cheeses from raw milk. For this reason, it is essential that the raw material from dairies is of good quality to minimize risks to consumers. Thus, this study aimed to evaluate the quality of milk in artisanal cheese factories in Rio Grande do Norte, Brazil. Fifty samples were collected from areas that stand out in dairy production in the state. These samples underwent microbiological and physical–chemical analysis, as well as antibiotic residue and fraud searches. Viable strict and facultative mesophilic bacteria were surveyed, in addition to total and thermotolerant coliforms, Salmonella sp., and Staphylococcus aureus; titratable acidity in Dornic degrees, density, cryoscopy, stability to alizarol, and percentages of protein, lactose, and fat contents were also measured, and tests for residues and recurrent fraud in milk were conducted. In general, all samples exceeded the limit established by law for mesophilic bacteria counting; Salmonella sp. was found in one sample. Given this contamination, the acidity of 76% of the samples was higher than allowed by the legislation. Regarding fat and protein parameters, 14% and 10% of the samples were below the required values by the legislation, respectively. Furthermore, there is suspicion of fraud by adding water in 24% of samples. Chlorides were found in 16% and antimicrobial residues in 46% of samples. Therefore, the quality of the milk used in informal artisanal cheese making in the state of Rio Grande do Norte is poor and may pose a risk to consumers, with the loss of quality of coalho and butter cheeses.