Proximate composition and anti-oxidant activity of organically- and conventionally-grown broccoli (Brassica oleracea L. var. italica)

Abstract

Increasing interest in organic cultivation led us to undertake a comparative study between organically- and conventionally-grown broccoli during succesive phases of their growth. The results showed similar proximate compositions in organically- and conventionally-grown crops. Carbohydrate levels were highest (120.6 and 116.6 g kg–1, respectively) at the time of commercial harvest. Broccoli was a good scavenger of peroxyl (50% inhibition) and hydroxyl (65% inhibition) radicals, with no significant differences between those crops grown organically or conventionally.Trolox equivalent anti-oxidant capacity (TEAC) values were slightly higher during all three phases of growth in organically-grown broccoli compared to conventionally-grown broccoli.TEAC values decreased as growth progressed, from 12.80 in Stage 1 to 8.58 in Stage 3 in organically-grown broccoli, and from 10.84 to 5.56 in the equivalent Stages in conventionally-grown broccoli.