Effects of ozone treatment on medium hard wheat (Triticum aestivum L.) flour quality and performance in steamed bread making

The quality characteristics of medium hard wheat flour were investigated after treatment with ozone gas (5 mg/L at 3.3 L/min) as a function of time (0, 0.5, 1.0, 1.5 and 2.0 h) in the study. Results indicated that the wet gluten content and whiteness of wheat flour increased significantly (P < 0.05) compared with the control. However, alpha-amylase activity, peak viscosities, hot paste viscosity, and cold paste viscosity decreased significantly (P < 0.05) during oxidation. For the microstructure, starch granules were reduced in size with ozone treatment and all became single starch granules after 1.5 h treatment. Ozone treatment time for 1.0 h had positive effects on quality scores, volume/weight, height, skin color, skin structure, external appearance and internal structure. Ozone treatment was beneficial in wheat flours to obtain improved steamed bread properties.