Effect of yeast, fermentation time and frying temperature on the amount of acryl amide and chemical properties of donut

Donut is one of the most popular fried bakery products among consumers. This product is susceptible to the formation of acryl amide during processing. In this study, the effect of frying temperature (160, 170 and 180 ° C), the amount of yeast (0.5, 1 and 1.5 %) and the fermentation time (30, 45 and 60 min) on the physicochemical properties (moisture content, acidity, pH, total sugar, reducing sugars, color) and the amount of acryl amide in the final product was evaluated. The results showed that the amount of yeast, fermentation temperature and frying time affect many chemical properties (moisture, pH, acidity, protein, total sugar and color) as well as the formation of acryl amide in the final products. Increasing amount of yeast and frying temperature, the moisture content and total sugar of products increased and decreased, respectively. Increasing the amount of yeast caused a significant decrease in the amount of acryl amide in the final product, but fermentation time was not significantly effective on the amount of acryl amide in the final product. It was also found that increasing the temperature from 160 to 180 ° C increased the acryl amide content from 13.24 µg kg-1 to 27.34 µg kg-1. Finally, it was found that the adjustment process can reduce the formation of acryl amide in donuts products.