Study of quality changes in high moisture wheat after hot air drying

Abstract

Objective: To study the effects of different drying processes on the quality of high moisture wheat. Methods: Investigates the changes of wheat quality under different drying processes in three dimensions: appearance quality, nutritional quality and processing quality. Three indicators, namely colour, wet gluten content and drying rate, were selected as response values and combined with response surface analysis to predict the optimal drying process for high moisture wheat. Results: Drying temperature was the main influencing factor. As the temperature increased, the colour of the wheat deepened, the crude protein content decreased, the wet gluten content decreased, the water absorption of the dough increased, the formation time increased, the stabilization time increased, the degree of weakness decreased, the flour quality index under increased, The wheat skin changed from a small raised rectangle to a small sunken pit, and the internal starch granules changed from a smooth round or oval shape to a rough irregular shape. The optimal processing conditions of the response surface were drying temperature 45 ℃, wind speed 0.94 m/s, tempering time 30.4 min. The colour L* 58.811, the wet gluten content of 27.292%, the drying rate of 8.146×10-2%/min and the comprehensive score of 0.613 were obtained with this parameter. Conclusion: The study proved that the optimization of the hot air drying process improved the post-drying quality of wheat to some extent on the basis of ensuring the drying efficiency.

Keywords

• high moisture wheat
• hot air drying
• drying efficiency