Processing techniques alter resistant starch content, sugar profile and relative bioavailability of iron in groundnut (Arachis hypogaea L.) kernels

Abstract

The effect of processing techniques (soaking, roasting and microwave irradiation) on biochemical parameters of groundnut, especially resistant starch (RS) and non-resistant starch (NRS), along with phytic acid (PA), iron (Fe), PA/Fe molar ratio and sugars were studied. Changes in RS and NRS content after processing have not been reported yet. Roasting for 12 min at 160 °C caused an increase in RS (61.1 %) and NRS (67.2 %) content in the GAUG-10 genotype. Water-soaking of kernels for 8 h reduced the amount of PA and increased the amount of Fe and the molar ratio of PA/Fe. Processing techniques reduced sugar alcohols (inositol and mannitol) and stachyose content in groundnut kernels. Variation in nutritional and antinutritional traits of groundnut influenced by processing technique suggests a degree of genotypic tolerance.