Effect of microencapsulation of dietary oil on postprandial lipemia

Microencapsulation is increasingly applied to dietary oils, but only limited information is available about the effect on bioavailability. The aim of the present study was to evaluate the bioavailability of microencapsulated vegetable oil from a liquid food product in a clinical trial. Another aim was to compare the suitability of sodium octenyl succinate starch (SOSS) and oat starch aggregate (OSA) in sustained release of a vegetable oil. Twenty-four healthy young men were recruited and randomly allocated into 1 of 3 groups (A, B, C). All subjects consumed 2 liquid test meals, which differed only with respect to microencapsulation. Groups A and B consumed berry juice or fermented oat drink, respectively, containing either non-encapsulated or SOSS-encapsulated blackcurrant seed oil (BCO). Group C received sea buckthorn oil (SBO) encapsulated with SOSS or OSA. Blood samples were collected at 0, 30,60,90,180,270, and 360 min after the meal, and chylomicron-rich (CM-rich) fraction was separated for subsequent triacylglycerol (TAG) analysis. Microencapsulation increased the glycemic response. SOSS-encapsulated BCO resulted in a similar CM-rich TAG response as non-encapsulated BCO, indicating that the SOSS-encapsulated oil was fully bioavailable. OSA-encapsulation had a similar bioavailability. The lipemic response of subjects who consumed the oil mixed in the fermented oat drink was higher than that of other subjects. This most likely resulted from the slightly higher fat and energy content of the fermented oat drink compared with berry juice. Contrary to expectations, the use of OSA in microencapsulation did not result in sustained release.