Abstract
This study investigated the effects of sequential high-pressure homogenization followed by heat treatment on the physicochemical properties and lipidomic characteristics of liquid egg (LE) and liquid egg yolk (LEY). After treatment, homogenization and heat-treated liquid egg (H-LE) and homogenization and heat-treated liquid egg yolk (H-LEY) exhibited significantly enhanced flowability and thermal stability, with gelation temperatures increasing from 65°C to 82°C for H-LE and from 82°C to 95°C for H-LEY. In vitro digestion analysis revealed that H-LE demonstrated a 14.8 % higher hydrolysis degree compared to unmodified controls, indicating enhanced digestibility. Quantitative lipidomics analysis using LC-MS/MS identified 894 lipid molecules across 25 subclasses, with minimal changes in total lipid abundance after modification. However, significant decreases were observed in specific phospholipids, particularly 14 phosphatidylserine species in H-LE and 10 phosphatidylcholine species in H-LEY, suggesting selective phospholipid hydrolysis. While the modification process reduced overall lipid unsaturation, the content of nutritionally valuable polyunsaturated fatty acids (DHA, EPA, LA, and ARA) remained largely unchanged, though their molecular forms shifted from triglycerides to phospholipids, particularly in H-LE. Notably, PE-EPA content increased significantly in both modified products (from 39.75 % to 43.34 % in H-LE and from 34.58 % to 36.53 % in H-LEY). These findings demonstrate that combined high-pressure homogenization and heat treatment effectively improves egg liquid functionality while maintaining essential nutritional components, offering potential for developing enhanced egg-based products with superior processing characteristics and bioavailability.