Effect of microwaves on technological and rheological properties of suni-bug (Eurygaster spp) damaged and undamaged wheat flour

Abstract

In this study, the effects of microwave application on technological and rheological properties of flours produced from sound and damaged wheat by suni-bug (Eurygaster spp.) were investigated. The flour samples were exposed to microwave energy in various times (90, 120, 180, 240, 300 s) by using a closed system at 625 W. Existing of suni-bug damage in flour samples was determined by modified Zeleny sedimentation test before microwave application. Total protein, the standard and modified Zeleny sedimentation test, wet gluten, standard and modified Perten gluten indexes, falling number, and alveographe test of the flour samples were carried out. The results were evaluated statistically and summarized as below (p<0.05). The moisture values (15.2-12.0 %), wet gluten contents (28-20.4 %), proteolytic activity (40.20-6.96 %), zeleny sedimentation (31.8-15.8 ml) and alveogram energy (W) values (192-92 10-4 J) among samples decreased whereas Perten gluten index (78-100 %) and falling number values (264-397 s) of flour samples increased with processing microwave times. The total protein content of samples was not affected significantly (p<0.05) by heating with microwave treatment. These results suggested certain microwave treatment times (120-180 s) caused positive effects on thermal inactivation of insect enzyme damage of wheat according to some physicochemical quality parameters (Zeleny sedimentation, Perten Gluten index and alveogram values).