Hydrolysis-Driven interfacial modification regulates the functional transition of Idesia polycarpa oil bodies during aqueous enzymatic extraction

Hydrolysis time tuned Idesia polycarpa oil body recovery & functionality. • Moderate hydrolysis improved dispersion while preserving oil-body integrity. • Increasing interfacial protein accessibility improved emulsifying performance. • Controlled hydrolysis enhanced the oxidative stability of plant oil bodies. Oil bodies (OBs) are natural lipid-based structures with unique interfacial properties; however, achieving efficient recovery while maintaining their structural and functional integrity remains challenging. This study investigated the hydrolysis-time-dependent regulation of Idesia polycarpa oil bodies (IPOBs) during Viscozyme® L-assisted aqueous enzymatic extraction (0–180 min). Cell-wall modification and changes in IPOB-associated non-lipid components were assessed by measuring IPOB-bound total sugars and total phenolics, which peaked at 120 min (135.20 ± 2.80 g/kg DW and 5.40 ± 0.15 g GAE/kg DW, respectively). IPOBs treated for 150 min exhibited the smallest particle size (2.21 μm) and the most negative zeta potential (−16.21 mV), making this condition advantageous when emulsifying activity is prioritized. In contrast, IPOBs treated for 120 min (IPOBs-120) showed the most favorable overall balance, with higher oxidative stability during storage, a lower peroxide value (∼2.9 mmol/kg oil), reduced TBARS formation (∼0.67 mmol/kg oil), and high ABTS radical scavenging activity (93.76%). Excessive hydrolysis (180 min) reduced IPOB-bound sugars to 95.50 g/kg DW and was accompanied by deterioration in colloidal and functional stability. Multivariate analysis revealed a clear transition from insufficient matrix disruption to functional optimization and, ultimately, over-hydrolysis-induced deterioration. These findings demonstrate that hydrolysis time is a critical processing parameter for producing stable IPOBs with tunable functional properties and provide a theoretical basis for their development as natural emulsifiers, plant-derived lipid ingredients, and carriers of lipophilic nutrients or bioactive compounds in complex food systems. Download: Download high-res image (400KB) Download: Download full-size image