| Popis: |
We evaluated the effects of soluble fiber, including oligosaccharides, and resistant starch on the micellarization of lutein, α-carotene, and β-carotene from a raw spinach and carrot “salad” using a simulated in vitro digestion. Fiber variables were either combined with raw salad alone or with raw salad and nonfat yogurt to simulate a more complex meal. Raw and ripe bananas were used to examine the potential impact of the natural, inherent resistant starch fiber in the banana on the micellarization of lutein, α-carotene (AC), and β-carotene (βC). It was expected that the soluble fibers, fructooligosaccharide (FOS), galactooligosaccharide (GOS), and pectin, as well as fibers displaying characteristics of soluble fiber, such as resistant starch (RS) would decrease xanthophyll and carotene micellarization as previous soluble fiber studies had shown in vitro and in vivo. The efficiency with which lutein, 13-cis-β-carotene, α-carotene, β-carotene, and 9-cis-β-carotene from the raw salad partitioned in the aqueous fraction were 54.1 ± 1.3%, 18.5 ± 0.6%, 22.0 ± 1.4%, 19.6 ± 1.0%, and 52.7 ± 2.2%, respectively. High viscosity citrus pectin significantly inhibited micellarization of lutein (α< 0.0001), 13-cis-β-carotene (α< 0.0001), α-carotene (α< 0.0001), β-carotene (α< 0.0001), and 9-cis-β-carotene (α< 0.0001) relative to the fiber free control at 4% (wt: wt). Unexpectedly, oligosaccharide and resistant starch samples (FOS, GOS, RS2, and RS3) significantly increased micellarization of lutein, AC, and βC. Micellarization of lutein in the spinach and carrot salad was significantly increased by 12%, 12%, and 14% with the addition of 2% FOS (α= 0.0377), 4% FOS (0.0306), and 2% RS3 (α= 0.0054), respectively. Alpha- and beta-carotene showed very similar results. Micellarization of beta-carotene was significantly increased by 41%, 60% and 49% with the addition of 2% (wt: wt) FOS (α= 0.0136), RS2 (α< 0.0001), and RS3 (α= 0.0014), respectively. Micellarization of beta-carotene cis isomers was significantly increased with the addition of both 2% and 4% (wt: wt) FOS, GOS, RS2 and RS3. The combination of yogurt and salad did not significantly affect micellarization of lutein, AC or βC. There was no significant difference in extent of micellarization of carotenoids between raw and ripe banana. The results from this study indicate that the presence of 2-4% FOS, GOS, and RS ingredients will not compromise the bioaccessibility of carotenoids in a meal. |
