Fluctuations in Goat Milk Composition During Processing

An elevated somatic cell count (SCC) affects the physicochemical characteristics of milk, altering its renneting ability and ultimately impacting the yield and quality of the cheese produced. This study aims to analyse the variations in the composition of Latvian goat milk and its technological properties in relation to SCC. Individual goat milk samples (n = 240) were collected from one of the largest goat farms in Latvia during 2019 and 2020. Latvian, Saanen, and cross-breed goat milk samples from different lactations were tested for their chemical composition (fat, protein, lactose, dry matter, and SCC), fat-to-protein ratio, freezing point, and curd firmness. Samples were collected during different lactation periods in order to analyse the seasonal effect on milk quality. The results demonstrated that milk samples from goats with lower SCCs (Group I) exhibited the highest fat (3.34%), lactose (4.56%), and dry matter (11.28%) concentrations and fat-to-protein ratios (1.02). Curd firmness decreased progressively from Group I to Group IV, fluctuating between Latvian Native (1.96–1.47 N), Saanen (1.91–1.59 N), and cross-breed (1.66–1.58 N) goat milk samples. A significantly lower (p = 0.030) curd firmness (1.56 N) was determined in the Group IV goat milk samples. Seasonal fluctuations in milk composition were observed in relation to curd firmness, which peaked in late lactation milk (3.85 N), although minor fluctuations were observed in protein concentrations (3.23% to 3.30%) across the sampling periods (2019 and 2020). These findings highlight the necessity of SCC monitoring in Latvian goat milk to ensure appropriate quality for milk processing.