Characterization and storage stability of spray dried soy-rapeseed lecithin/ trehalose liposomes loaded with a tilapia viscera hydrolysate

Drying-induced stabilization is a challenge that delivery systems still face. This study aims to investigate the effects of adding trehalose to spray dried soy-rapeseed lecithin liposomes, and the storage stability of the dried liposomes loaded with a tilapia viscera protein hydrolysate, during 42 days at 4 degrees C and 23 degrees C, and at different relative humidity (RH). Particle size increased from 215 to 250 nm in fresh liposomes to 258-314 nm after spray drying according to trehalose concentration, all preparations showing a strong electronegative zeta Potential (-48.5 to -59.9 mV). Dried liposomes stored at 4 degrees C maintained lower polydispersity and higher solubility than those stored at 23 degrees C. Changes in water activity (Aw), FTIR and DSC revealed structural changes in samples stored at 23 degrees C and high RH. Spray dried hydrolysate-containing liposomes could be considered as a functional food ingredient due to the substantial antioxidant activity and angiotensin-converting enzyme (ACE) inhibitory capacity after in vitro simulated gastrointestinal digestion. Industrial relevance: The availability of a natural liposomal preparation in dry powder form, capable to maintain its bioactive properties, is a great advantage for the functional food industry, since it favours the stability, transport and storage of the ingredient prior to use, and allows great versatility to be incorporated in solid restructured products.

Automated summary

This study investigated the effects of adding trehalose to spray dried soy-rapeseed lecithin liposomes and the storage stability of dried liposomes loaded with a tilapia viscera protein hydrolysate under different conditions. The findings suggest that spray dried hydrolysate-containing liposomes could be considered as a functional food ingredient due to their antioxidant activity and ACE inhibitory capacity. This natural liposomal preparation in dry powder form may offer advantages for the functional food industry by maintaining bioactive properties and providing versatility for use in solid restructured products.