Elaboração e atuação antimicrobiana do extrato de própolis incorporado no queijo cottage

Abstract

Cottage cheese is characterized as a fresh, creamy curd with low acidity, containing about 80% moisture and 4% fat, generally having a lower fat content than most other cheeses. Due to its high moisture content, the cheese is highly perishable, and its composition favors microbial proliferation. Therefore, various methods are studied to preserve and ensure the quality of cheeses, including the use of propolis extract, which has shown biological and antimicrobial potential in foods. Propolis is a complex mixture of resinous, gum, and balsamic substances, with varying texture and color. Collected by bees from parts of plants such as flower buds and shoots, it is composed of 50% resin and plant balm, 30% wax, 10% essential and aromatic oils, 5% pollen, and 5% other substances. Thus, a cottage cheese incorporating propolis extract was developed, following a methodology using UHT skim milk, and fermentation was carried out with Bela Vista® yeast, adding 1% and 2% propolis extract. Its composition was also evaluated through physicochemical analyses, determining total proteins, total lipids, ash content, calculating the total carbohydrates, and moisture content. The characterization results were similar to those found in the literature, and the cheese samples with and without propolis extract did not show significant differences. For the evaluation of antimicrobial activity, microbiological analysis of mesophilic aerobes in plates and coliforms was performed, showing good performance of the propolis extract in the mesophilic aerobes plate test. As for coliforms, the presumptive test did not produce gas for any of the samples. Finally, a sensory analysis was conducted to assess the acceptance of propolis extract; however, the samples with propolis were not well accepted by the evaluators, receiving a lower score than expected.