Evaluation of Qualitative, Functional and Bioactive Properties of Bugged Wheat

Despite all the progresses made in the field of pest control, bug is yet the hazardous pest in Iran. This insect injects a salivary proteinase into immature wheat kernels resulting in poor rheological properties, which leads to having bread with low volume and unacceptable texture. On the other hand, protein hydrolysis of gluten can improve the functional properties and also body physiological mechanisms according to producing bioactive peptides. In this study wheat samples with variable proportion of bug-infested grains (25, 50, 75 and 100%) were initially prepared and then qualitative, functional and bioactive tests were performed to evaluate the effect of suni-bug damage. Results showed that Zeleny sedimentation value decreased by increasing bug damage in samples indicating low quality in gluten for bread making. On the other hand, by increasing proportion of bug damage, degree of hydrolysis increased and functional properties of wheat samples such as solubility and emulsifying capacity were improved. By increasing the degree of hydrolysis, protein solubility also increased and the highest emulsifying capacity was observed in 25% suni-bug wheat sample. The results of evaluating bioactive properties in wheat samples indicated that by increasing the degree of bug attack, producing short peptides with ACE inhibitory and antioxidant activity increased, therefore the highest percentage of ACE inhibition and antioxidant ability is observed in 100% suni-bug damaged sample whereas the lowest was evidenced in the sound wheat sample.