PHYSICOCHEMICAL CHARACTERIZATION OF MILK AND ARTISANAL BUTTER CHEESE ACCORDING TO A1 AND A2 β-CASEIN GENOTYPES IN THE SERRA DE SANTANA REGION, RIO GRANDE DO NORTE, BRAZIL
β-casein; Artisanal; A2 Test
A2 milk has emerged in the market as an alternative for individuals experiencing digestive issues related to the type of β-casein genotype; however, it is necessary to understand its physicochemical composition in comparison with A1 milk. This study aimed to characterize the composition of A1 and A2 milk and the compositional characteristics of butter cheese produced from A1 and A2 milk. The study was conducted based on data collection from herds of lactating cows belonging to 20 milk producers in the Serra de Santana microregion, from October 2024 to June 2026, comprising 267 cows and 278 milk samples, which were pooled into 54 milk pools. The variables analyzed included fat, protein, lactose, total solids, non-fat solids, casein, and casein percentage. For butter cheese analyses, eight samples were produced between April and June 2026. Comparison of two means was performed using Student’s t-test. For multiple comparisons, data were subjected to analysis of variance (ANOVA), followed by Fisher’s least significant difference (LSD) test, considering a 5% significance level. For cheese samples, descriptive analysis was performed. For all evaluated variables, no significant differences were observed between A1 and A2 milk samples (P > 0.05). A2 milk showed mean values of 3.46% fat, 3.24% protein, 4.51% lactose, 12.19% total solids, 8.73% non-fat solids, 2.50% casein, and 76.83% casein percentage, with no statistical differences compared to A1 milk. Seasonality also did not influence the observed results. Similarly, butter cheese samples produced from both milk types showed no statistical differences, with values of 40.96% moisture, 24.69% protein, and 2.56% ash.