Enzymatically produced acylglycerol and glycerin monostearate additives improved the characteristics of gelatin-stabilized omega-3 emulsions and microcapsules.

The impacts of enzymatically produced acylglycerol and glycerin monostearate on the characteristics of gelatin-stabilized omega-3 emulsions and microcapsules were investigated. Tuna oil was enzymatically produced and the resulting acylglycerol was mixed with tuna oil at 12.5% (w/w) to prepare a novel oil phase. This oil phase was stabilized by gelatin to prepare oil-in-water emulsions and subsequent microcapsules via complex coacervation. The tuna oil with glycerin monostearate (GMS) at 1 and 2% (w/w) were used as controls. Results showed that both acylglycerol and GMS significantly reduced the emulsion droplet size and zeta potential, while increasing the viscoelasticity and stability. The diacylglycerol/monoacylglycerol were involved in the oil/water interfacial layer formation by lowering interfacial tension and increasing droplet surface hydrophobicity. Overall, the changed emulsion properties promoted the complex coacervation and contributed to the formation of microcapsules with improved oxidative stability. Therefore, enzymatically produced acylglycerol can develop high-quality stable omega-3 microencapsulated novel food ingredients.

Comparative Lipidomics Profiling of Acylglycerol from Tuna Oil Selectively Hydrolyzed by Thermomyces Lanuginosus Lipase and Candida Antarctica Lipase A.

Lipase hydrolysis is an effective method to develop different functional types of lipids. In this study, tuna oil was partially hydrolyzed at 30% and 60% by Thermomyces lanuginosus lipase (TL 100 L) and Candida Antarctica lipase A (ADL), respectively, to obtain lipid-modified acylglycerols. The lipidomic profiling of the acylglycerols was investigated by UPLC-Q-TOF-MS and GC-MS to clarify the lipid modification effect of these two lipases on tuna oil. The results showed that 247 kinds of acylglycerols and 23 kinds of fatty acids were identified in the five samples. In the ADL group, the content of triacylglycerols (TAG) and diacylglycerols (DAG) increased by 4.93% and 114.38%, respectively, with an increase in the hydrolysis degree (HD), while there was a decreasing trend in the TL 100 L group. TL 100 L had a better enrichment effect on DHA, while ADL was more inclined to enrich EPA and hydrolyze saturated fatty acids. Cluster analysis showed that the lipids obtained by the hydrolysis of TL 100 L and ADL were significantly different in the cluster analysis of TAG, DAG, and monoacylglycerols (MAG). TL 100 L has strong TAG selectivity and a strong ability to hydrolyze acylglycerols, while ADL has the potential to synthesize functional lipids containing omega-3 PUFAs, especially DAG.