Vol. 9, Special Issue 1, Part I (2025)

This study explores the effect of different heat treatments (72 °C/15s, 85 °C/10min, and 121 °C/15min) on the biofunctional properties of fermented goat milk, with a focus on protein profile, antioxidant, antimicrobial, and antihypertensive activities. The protein profiles were analyzed using SDS-PAGE, revealing that fermentation and heat treatments significantly impacted the milk proteins. Caseins showed reduced intensity over the 21-day storage period, with the most degradation observed in samples heated to 121 °C. Whey proteins, such as β-lacto globulin (β-Lg), were more susceptible to heat-induced degradation, particularly at 121 °C. Antioxidant activity, measured through radical scavenging activity (RSA), increased progressively throughout the storage period for all heat treatments, with the highest RSA observed in milk heated to 121 °C. The RSA increased from 45.36% to 64.63% for 72 °C/15s, 43.25% to 61.78% for 85 °C/10min, and 51.18% to 70.20% for 121 °C/15min. Antimicrobial testing revealed that fermented milk heated at 85 °C exhibited significant antibacterial activity against E. coli, but no activity was detected against B. cereus, S. aureus, or S. enterica. Scanning electron microscopy showed that antimicrobial peptides from the milk disrupted the bacterial membrane. Additionally, the ACE inhibitory activity, a marker for antihypertensive potential, increased with fermentation, with the highest activity recorded at 85 °C/10min, reaching up to 71.68% by day 14, after which a slight decrease was observed. These results suggest that heat treatment and fermentation improve the biofunctional properties of goat milk, particularly enhancing antioxidant and antihypertensive activities, with potential applications in developing hypoallergenic and functional dairy products.