Aspectos tecnológicos do queijo Minas Frescal produzido a partir de leite A1 e A2 para beta-caseína

Abstract

Cow's milk is considered a complete food, consisting of approximately 87% of water and 13% of solid compounds, being 3.9% represented by lipids; 3.4% protein; 4.8% lactose, vitamins and only 0.8% corresponding to minerals. Of the 80% proteins are caseins, and among the organic structures of casein, β-casein corresponds to 25-35%, due in 13 known allelic variants, where the most common forms are casein encoded by alleles A1 and A2. Digestion of β-casein A1 produces a bioactive peptide that is related to human disease cases. Since β-casein A2 does not produce this bioactive product when it is digested, therefore, milk with higher amounts of β-casein A2 is less likely to cause the same health problems as milk with β-casein A1. Given the benefits found in this milk, we sought to produce Minas Frescal cheeses from milk of cows with different genotypes for β-casein (A1A1, A1A2 and A2A2) and evaluate their technological and sensory aspects. Minas Frescal cheese was produced due to its easy manufacturing process and being one of the most popular cheeses in Brazil. For the production of Minas Frescal cheeses, milk from 15 Holstein and 15 Girolando cattle with different genotypes for β-casein (A1A1, A1A2 and A2A2) was used. The entire experimental group defined was divided into 3 groups: group A1A1 composed of 10 animals, 5 of Girolando and 5 of Holstein; group A1A2 composed of 10 animals, 5 of them Girolando and 5 of the Holstein and group A2A2 composed of 10 animals, 5 of Girolando and 5 of Holstein. In the collected milks were performed physical chemical analysis of density at 15ºC, titratable acidity, pH, fat and Total Dry Extract (EST). The cheeses produced were evaluated under physicochemical, sensory and yield aspects at 4 cold storage times - 1, 7, 14 and 21 days. It is observed from the Minas Frescal cheeses produced that there was a statistical difference (p>0.05) in the moisture content, fat in the dry extract, ashes and pH. Cheese produced with β-casein A2A2 milk had a higher yield. The A2A2 genotype showed significant difference (p>0.05) in relation to the other treatments evaluated. Technological advantages were obtained as a greater fat recovery in cheese and a lower fat loss in whey. Over time during cheese storage it was observed that the texture properties such as hardness, adhesiveness, cohesiveness, elasticity and chewability also showed significant difference (p>0.05). In the sensory attributes, advantages were detected in the taste attributes and overall aspects in A2A2 treatment, thus showing a good acceptance of cheese made from β-casein A2A2 milk. From the results obtained we can conclude that the production of cheese with milk A2 showed good results that can represent a differential for the consumer market, since, besides the benefits related to yield and texture, milk A2 is pointed as having a higher digestibility which helps in the quality and preservation of consumer health.