Technological and chemical characters of bread prepared from irradiated wheat flour

The present work is a part of research programme aimed to use gamma irradiation to decrease the growth of fungi and the concentration of mycotoxines which present naturally in collected samples of wheat flour from Egyptian markets (first part). To follow the technological, rheological and chemical characters of bread "Balady" common type in Egypt, same samples of wheat flour were irradiated with 2, 4 and 8 kGy for these purposes. The Egyptian bread type (Balady) had been prepared from irradiated and non-irraidated samples. The chemical analysis proved a significant induction in reducing sugars (RS) which increased gradually with increasing doses as 16.75%, 30.30%, 43.24% after using 2, 4 and 8 kGy respectively. Same trend was observed with total sugars (TS), less changes were observed in non-reducing sugars (NRS) and starch content. Results obtained showed that an actual reduction in dough development time, stability, weaking of dough and height of bread especially for irradiated samples at 4 and 8 kGy but 2 kGy was less effective. The reduction of Alkaline Water Retention Capacity (AWRC) was clear at high doses whereas 2.0 kGy improved the freshness of aged "balady" bread. Concerning, the evaluation of organoleptic characters of bread as judged by the panelists, all the samples were accepted either irradiated or not. But, the lowest values of acceptance resulted from irradiated samples with 4 and 8 kGy. Therefore, using 2 kGy can be recommended for keeping quality of wheat flour to avoid the infestation or pathogenic infection. Whereas high doses (4-8 kGy) can be use for eliminating the mycotoxins with some changes of quality which can be overcome by using some additional matters to get more acceptable bread and less changes in technological characters.