3.4. Antioxidant properties
Fruits contain many compounds that display antioxidant functionalities.
Therefore, to measure the antioxidant capacity of each
compound individually is a complex and difficult undertaking. Several
methods have been developed to estimate the total antioxidant
capacity of different plant materials (Guo et al., 2003).
Usually, these methods measure the ability of antioxidants to scavenge
specific radicals, to inhibit lipid peroxidation or to chelate
metal ions. The use of simple ‘‘total antioxidant capacity’’ methods
differing in their way of generating free radicals, the strategy to
measure the end point of the inhibition reaction, and the sensitivity
towards the different reducing molecules in the sample (Roginsky
& Lissi, 2005). Therefore, more than one method should be
used to gain a more complete picture of the antioxidant capacity
of phenolic compounds, as illustrated by the data in Table 4 that
show the antioxidant activity of dietary fibre concentrates obtained
from exotic-fruit co-products using each of the ABTS, DPPH,
and FRAP assays and expressed as lM Trolox equivalent (TE)/g