Anti-nutritional compounds in fresh and dried lychee fractions (Litchi chinensis Sonn.)

Abstract

The present study evaluated the anti-nutritional factors of “Bengal” lychee (Litchi chinensis Sonn.), in the fresh pulp, peel and seed, both fresh and processed. The samples were analyzed for the levels of phenolic compounds, nitrate, oxalic acid and inhibitory activities of trypsin, lipase and α-amylase. Drying influenced the activity of all enzyme inhibitors, resulting in a reduction in the inhibitory activity of lipase (0.13 and 0.15 lipase inhibitor units for peel and seed, respectively) and an increase in the inhibitory activities of trypsin (10.14 and 10.66 trypsin inhibitor units for peel and seed, respectively) and α-amylase (1.13 and 1.08 amylase inhibitor units for peel and seed, respectively). With drying, it was possible to observe an increase in the levels of phenolic compounds, the low content of nitrate did not change with drying, while oxalic acid was not detected. The antinutrients evaluated in lychee fractions are present in amounts that do not preclude its use; thus, the use of lychee fractions, fresh or dried, is feasible as nutrient sources and add value to the fruits, since industries can use these residues for developing new products, as well as in food enrichment.