Changes of extracellular vesicles in goat milk treated with different methods

This study explored the effects of four processing treatments on goat milk-derived extracellular vesicles (EVs). Raw goat milk of four groups was heated at 65 °C for 30 min (pasteurization), 120 °C for 3 s (high-temperature heating), ultrasonic treatment (480 W) for 10 min, and microwave (800 W) for 50 s, respectively. EVs were extracted by ultracentrifugation. The particle size, concentrations of protein, specific marker proteins (TSG101 and HSP70), and total EVs-derived RNA of precipitation of enriched EVs were determined. The results showed no significant changes in particle sizes, TSG101, and HSP70 after pasteurization, but protein concentration increased significantly, and total RNA decreased markedly. The particle size, total EVs-derived RNA, and expression levels of TSG101 and HSP70 were all significantly decreased by high-temperature heating, ultrasonic treatment, and microwave. The study suggested that both high-temperature and microwave treatments significantly decrease the particle sizes, total RNA concentration, and the abundance of specific marker proteins of EVs. • Pasteurization had little effect on particle size, morphology and some components of EVs in goat milk. • High temperature heating and microwave have a large effect on the size, morphology, and certain components of EVs. • The effect of ultrasound on morphology of EVs was not obvious, it had a greater effect on the size and components of EVs.