Microbiological and physicochemical analyses are important parameters to determine the shelf life and food safety. The aim of this study was to evaluate the microbiological and physicochemical parameters of 101 samples of pasteurized milk collected from dairies located in COMCAM region, Brazil. For microbiological analyzes, coliforms at 35&deg;C and 45&deg;C, and mesophilic aerobic bacteria counts were performed. The physicochemical parameters investigated were alkaline phosphatase, peroxidase, and cryoscopic index. According to the results, 21% of the samples were above the limit established by the Brazilian legislation for mesophilic bacteria counts, and 1% for coliform counts at 45&deg;C. For the physicochemical parameters, the analyses of peroxidase and cryoscopy index were not in accordance for 2% and 17% of the samples, respectively. The microbiological and physic chemical results showed that the quality conditions of some pasteurized milks was not adequate, possible due errors during their handling, processing and storage. These factors could result in potential health risks for consumers.<br />

Este trabalho propôs desenvolver um leite fermentado por Lactobacillus helveticus (LH) ou associada com cultura de Streptococcus thermophilus (LHST) adicionado de extrato de hibisco e avaliar a atividade antioxidante e evolução do crescimento das culturas láticas durante a estocagem sob refrigeração a 4 ± 1ºC. O leite fermentado recebeu extrato de hibisco na forma livre (LHExL e LHSTExL) ou encapsulado com PVP e Tween 80 (LHExE e LHSTExE). Avaliou-se a atividade antioxidante (DPPH e FRAP) nos tempos de 1, 15 e 30 dias. Os resultados demonstraram que o teor de acidez titulável foi inferior após a fermentação. A viabilidade das bactérias láticas foi satisfatória, as quais atenderam os requisitos legais e mantiveram estáveis até 30 dias de estocagem para ambas as caldas do leite fermentado (LH e LHST). A atividade antioxidante frente ao radical DPPH foi superior a 80%, porém não apresentou resultados conclusivos relativos à interação das culturas láticas e das diferentes formas de aplicação do extrato de hibisco. Porém, o LH apresentou maior atividade antioxidante pelo método FRAP quando associado ao extrato de hibisco encapsulado no tempo inicial. Esta análise permitiu observar que a associação do extrato de hibisco independente da forma veiculada ao leite fermentado aumentou a atividade antioxidante pelo método de FRAP e este manteve estável ao longo do tempo de estocagem. Portanto, o estudo permitiu concluir que o leite fermentado associado ao extrato de hibisco contribuiu com o aumento da atividade antioxidante e manteve estável ao longo do tempo de estocagem.

Brazil nuts are largely consumed either as a whole or as an ingredient in different food products. These seeds are rich in lipids that are susceptible to oxidation, which is the most common cause of deterioration in their sensory and nutritional quality. Active food packagings are a potential strategy to prevent food lipid oxidation. In this work, thermoplastic starch/poly (butylene adipate–co–terephthalate) (TPS/PBAT) containing water‐soluble curcumin and pinhão (Araucaria angustifolia) extract as natural antioxidants were used to package Brazil nuts (Bertholletia excelsa). Packaged nuts were stored under different temperatures and analysed for up to 30 days of storage. The lipid profile of the oil extracted from the nuts before packaging showed that it is rich in unsaturated fatty acids. The UV–Vis spectra were organized into an augmented matrix and then into a principal component analysis (PCA). Results showed that for 10°C, the control TPS/PBAT film and the film containing pinhão extract resulted in the best preservation. When evaluated at 25°C, the nuts packed in films that contained water‐soluble curcumin presented the best oxidative stability until the 15th day of storage. After this period, the oxidation reactions were significant for all samples, indicating a possible compromise on the sensory and nutritional quality of Brazil nuts.