Bacterial microbiota diversity in sheep milk during refrigerated storage under different processing conditions

Sheep milk, while nutritionally dense due to high calcium and B vitamins, spoils rapidly due to its diverse microbiota. Contamination risks arise from environmental Listeria or biofilm-forming microbes during milking and handling. This study employed 16 S rRNA gene sequencing to characterize microbial dynamics in sheep milk treated with ultrasound, pasteurization, and ultrasound/pasteurization during refrigerated storage. Analysis of 71 samples yielded 3,301,066 high-quality reads, revealing significant shifts in microbial community composition and diversity. Results revealed that Lactococcus was the primary bacteria causing deterioration in untreated sheep milk stored at 4 °C. In treated samples, the significant growth of Lactococcus and Hafniella obesoides were identified as the main cause of spoilage during 4 °C storage. This research provides valuable insights into bacterial influences on sheep milk under different processing conditions, offering potential for reducing milk losses during transportation, processing, and lowering costs in the dairy industry.