乳状液的组成及油滴粒径对β-胡萝卜素生物接近度的影响

目的:研究乳状液中β-胡萝卜素的胶束化过程以及油滴粒径、油相含量和β-胡萝卜素质量分数对乳状液中β-胡萝卜素生物接近度的影响规律及可能机制。方法:采用静态体外消化法,以胶束化率为指标评估β-胡萝卜素的生物接近度。结果:肠消化阶段的前30 min是乳状液中β-胡萝卜素胶束化过程的重要阶段;在一定范围内,β-胡萝卜素的胶束化率(3.23%~10.87%)与乳状液油滴粒径(0.44~4.28μm)呈线性负相关;油相含量1%~20%范围内,β-胡萝卜素的胶束化率随油相含量增加呈"S"型增长趋势;β-胡萝卜素的胶束化率随其质量分数的增加(2~30 mg/100 g)先上升后降低,相应地胶束中β-胡萝卜素的绝对质量先上升而后进入平台期。

Effect of Emulsion Composition and Oil Droplet Size on β-Carotene Bioaccessibility

Purpose: To investigate the process of β-carotene micellarization and evaluate the effect of oil droplet size, oilphase content and β-carotene concentration on the bioavailability of β-carotene incorporated in emulsions as well as toelucidate the possible mechanisms. Methods: The β-carotene bioaccessibility was assessed by in vitro digestion model. Thefraction of β-carotene transferred from the emulsion to a micellar phase was investigated. Results: Within the first 30 min ofduodenal digestion, the majority of lipid hydrolysis and β-carotene micellarization occurred. There was a negative correlationbetween the ratio of β-carotene incorporated into micelles and oil droplet size in the range from 0.44 to 4.28 μm. When theoil phase content increased from 1% to 20%, the bioaccessibility of β-carotene in the micellar phases presented a S-typegrowth tendency. The ratio of β-carotene incorporated into micelles increased significantly when β-carotene concentrationincreased from 2 to 30 mg/100 g and then tended to decrease when β-carotene concentration was further increased. However,the absolute amount of β-carotene incorporated into micelles increased first and then tended to remain stable.