Investigation the molecular degradation, starch-lipid complexes formation and pasting properties of wheat starch in instant noodles during deep-frying treatment

Abstract

The effects of frying temperature and time on the amylose content, thermodynamic properties, crystalline properties, and pasting properties of starch in wheat-flour based noodles were investigated. The amylose content increased when the frying temperature increased or the frying time extended. Differential scanning calorimetry confirmed the formation of starch-lipid complexes. ΔH of the complexes increased sharply from 0.91 to 1.40 J/g with increased frying temperature, while it initially increased from 1.01 to 1.40 J/g and then decreased rapidly to 1.17 J/g with prolonged frying time. These observations were consistent with the results of relative crystallinity. Rapid viscosity analysis showed that the viscosities decreased by the increasing frying temperature or the prolonging frying time. The results showed that the deep-frying process destroyed the starch structure and led to the formation of starch-lipid complexes.