Digestate Colloidal Properties Impacted by Emulsion Crystallinity Alter Static and Dynamic In Vitro Digestibility
The static and dynamic in vitro digestibility of similarly sized palm stearin (PS) and palm olein o/w emulsions stabilized with Span 60 was explored. PS emulsions were tempered to contain different levels of crystallinity (PS, PS-SE-25 °C and PS-LE) and compared with a completely liquid PO emulsion. Static in vitro digestion experiments used particle size distribution (PSD) analysis as an investigational tool to explore the reasons for lipolysis differences. Emulsion digestibility and bioaccessibility were also compared between the static and dynamic TIM-1 models, respectively. The results indicate that colloidal property differences in the gastric environment, impacted by triacylglycerol (TAG) crystallinity, altered lipid digestion. Increasing level of crystallinity attenuated early lipolysis among the PS samples, although ultimate lipolysis did not differ and the liquid control PO did not exhibit the highest degree of lipolysis as expected. The work has relevance to postprandial lipemia as lipid digestion can modulate lipemic response.