Impact of Fatty Acid Carbon Chain Length and Protein Composition on Physicochemical and Digestive Properties of <scp>MFGM</scp> Contained Emulsions

Improving fat digestibility is crucial for improving fatty acid intake in populations with weak digestive absorption capacities. Currently, research often analyzes the impact of triacylglyceride carbon chain length and emulsifier content on lipid digestion and absorption individually, overlooking their combined effects. This study aims to provide a reference for addressing the differences in fat digestibility between infant formula and breast milk by investigating the combined influence of these two factors on the physicochemical properties of droplet hydrolysis. The findings reveal significant differences in the interface substances and properties of lipid droplets composed of fatty acids with various carbon chain lengths. Emulsions prepared by OPO (long-chain fatty acids) exhibited the largest average particle size and greater stability compared to those with medium-chain fat (coconut oil) and ultra-long-chain fat (DHA algae oil). In addition, the protein composition and content on the surface of lipid droplets influenced the physical and chemical properties of emulsions. When whey protein and casein were added to a 6:4 ratio, the effect of fatty acid carbon chain length on the average particle and the emulsification characteristics of the lipid droplet interface were significantly reduced. Furthermore, emulsions composed of fat globules with a core of short-chain fatty acid or low surface protein content had higher lipolysis rates. These findings provide valuable insights for improving nutrient bioavailability in future food product developments, especially in enhancing infant nutrition.