Hydrophilic and lipophilic antioxidant capacity of commonly consumed South African fruits, vegetables, grains, legumes, fats/oils and beverages.

摘要

The antioxidant capacity of commonly consumed South African foods was determined using the fluorescein (FL)-based oxygen radical absorbance capacity (ORAC_FL) assay. The hydrophilic (H)-ORAC_FL of these foods ranged from 15 to 4202 micro mole Trolox equivalents (TE)/100 g, and the lipophilic (L)-ORAC_FL from 11 to 109 micro mole TE/100 g. The L-ORAC_FL of all the items analyzed contributed less than 5% of the total antioxidant capacity (TAC), except for sunflower oil (42%). Cultivar and seasonal availability influenced the H-ORAC_FL of some, but not all, fruits. The Golden Delicious apple cultivar has a lower (P<0.05) H-ORAC_FL (with peel and peeled) compared to the other apple cultivars analyzed. Household thermal processing decreased the H-ORAC_FL of cabbage, brown onion and baby marrow (zucchini) (P<0.05) and the L-ORAC_FL of potato and green beans (P<0.05). Although the H-ORAC_FL of refined grains (e.g. maize porridge) is among the lowest, such foods make a substantial contribution to the daily dietary intake of the South African population.