Evaluation of enterotoxins and antimicrobial resistance in microorganisms isolated from raw sheep milk and cheese : ensuring the microbiological safety of these products in southern Brazil

This study emphasizes the importance of monitoring the microbiological quality of animal products, such as raw sheep’s milk and cheese, to ensure food safety. In Brazil, there is currently no legislation governing the quality of sheep’s milk and its derivatives. Therefore, this study aimed to evaluate: (i) the hygienic-sanitary quality of raw sheep’s milk and cheese produced in southern Brazil; (ii) the presence of enterotoxins and Staphylococcus spp. in these products; and (iii) the susceptibility of the isolated Staphylococcus spp. to antimicrobial drugs and the presence of resistance genes. A total of 35 samples of sheep’s milk and cheese were examined. The microbiological quality and presence of enterotoxins were accessed using Petrifilm and VIDAS SET2 methods, respectively. Antimicrobial susceptibility tests were conducted using VITEK 2 equipment and the disc diffusion method. The presence of resistance genes tet(L), sul1, sul2, ermB, tetM, AAC(6)’, tetW, and strA were evaluated through PCR. In total, 39 Staphylococcus spp. were obtained. The resistance genes tetM, ermB, strA, tetL, sul1, AAC(6)’, and sul2 were detected in 82%, 59%, 36%, 28%, 23%, 3%, and 3% of isolates, respectively. The findings revealed that both raw sheep’s milk and cheese contained Staphylococcus spp. that exhibited resistance to antimicrobial drugs and harbored resistance genes. These results underscore the immediate need for specific legislation in Brazil to regulate the production and sale of these product

DESENVOLVIMENTO DE REQUEIJÃO CREMOSO SEM LACTOSE

Lactose intolerance is the name given to a dysfunction of the body, which has a deficiency or lack of production of enzyme lactase (β-galactosidase), responsible for the conversion of lactose into glucose and galactose. It is common in all age groups and ethnicities, its main consequence is the impossibility of ingesting products containing lactose, such as milk and its derivatives. Anticipating this, the food industry hydrolyzes lactose in order to obtain a product compatible with the disease, without compromising the characteristics already found in products without this treatment. Therefore, the objective of this work was to develop a “requeijão cremoso” without lactose. Skim milk were used as the main ingredient and β-galactosidase was added in concentrations of 0.07%, 0.1% and 0.2%, the hydrolysis time was 90 minutes at a pH of 6.55 and a temperature of 40 ºC. Analyses mode by high performance liquid chromatography showed that the degree of hydrolysis of the formulations was satisfactory. The developed product was adequate to the standards established by Brazilian legislation regarding to microbiological and physico-chemical standards. The sensorial analysis was performed with a hedonic scale of 9 points with a panel of 100 untrained judges, showing no statistically significant difference between samples of lactose-free and traditional curd. Thus, the formulation containing 0.07% of β-galactosidase enzyme can be considered a low-lactose curd, it is a good alternative for intolerants, since it has a similar taste and cost to the traditional one.A intolerância a lactose é o nome dado a uma disfunção do organismo que apresenta uma deficiência ou ausência da produção da enzima lactase (β-galactosidase), responsável pela conversão da lactose em glicose e galactose. É comum em todas as faixas etárias e etnias, sua principal consequência é a impossibilidade de ingestão de produtos contendo lactose, como leite e seus derivados. Antecipando-se a isso, a indústria alimentícia hidrolisa a lactose a fim de obter um produto compatível aos portadores dessa doença, sem comprometer as características já encontradas em produtos sem esse tratamento. Sendo assim, o objetivo deste trabalho foi desenvolver um requeijão cremoso sem lactose. Utilizou-se leite desnatado como matéria-prima e β-galactosidase em concentrações de 0,07%, 0,1% e 0,2%. O tempo de hidrólise foi de 90 minutos a um pH de 6,55 e temperatura de 40 ºC. A cromatografia líquida de alta eficiência demonstrou que o grau de hidrólise das formulações foi satisfatório. O produto desenvolvido adequou-se aos padrões estabelecidos pela legislação brasileira quanto aos limites microbiológicos e físico-químicos. A análise sensorial foi realizada com escala hedônica de 9 pontos com painel de 100 julgadores não treinados, não mostrando diferença estatística significativa entre amostras de requeijão sem lactose e tradicional. Sendo assim, a formulação contendo 0,07% de enzima β-galactosidase pode ser considerada um requeijão com baixo teor de lactose e é uma ótima alternativa para intolerantes, pois possui sabor e custo similar ao tradicional