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Overozonized wheat flour was added to unozonized wheat flour at three different ratios (M1: 1 : 1; M2: 1 : 2; and M3: 1 : 3), and the mixed flour was evaluated for quality properties, including pH, protein component, dough property, pasting property, and steamed bread quality. The pH of the mixed flour gradually increased as the addition content of overozonized flour decreased. The three mixed flour had higher insoluble polymeric protein (IPP) content than unozonized flour. Compared with overozonized flour, M1 and M2 flour did not show a significant difference in IPP content, but M3 flour exhibited a decreased IPP content. Three mixed flour had higher dough development time and dough stability time than both unozonized and overozonized flour, and there was no significant difference among three mixed flour in these two dough parameters. Peak, trough, and final viscosities of the three mixed flour were between those of unozonized and overozonized flour. Steamed bread of three mixed flour had larger specific volume and better texture than that of overozonized flour, with steamed bread of M3 flour showing the best attributes. Among the three mixed flour, M1 flour was the closest to overozonized flour in volatile compounds of steamed bread. These results suggested overozonized flour can be mixed with unozonized flour to decrease the deterioration of overozonization on the dough and food-making properties of wheat flour, but the mixing ratio should be taken into consideration to obtain a better quality.

Wheat flours were treated with ozone gas at low- and high-intensity conditions (0.61 and 3.82 g/h) for different durations (short: 5 min; long: 30 min), and the ozone-treated flours were evaluated in quality properties, including pH, protein component, water molecular mobility of dough, pasting property, and steamed bread quality. At both conditions, ozone treatment decreased the pH of wheat flour. Long duration of high-intensity treatment aroused significant increase in insoluble polymeric protein (IPP) content of wheat flour, but other treatments did not significantly change the IPP content. Dough of ozone-treated flour had higher water molecular mobility than that of native flour. Short duration of low-intensity treatment did not significantly change most pasting viscosity parameters of wheat flour, but other treatments increased the peak viscosity, breakdown viscosity, and setback viscosity. Steamed bread of ozone-treated flour had lower specific volume and pore uniformity than that of native flour. Long duration of high-intensity treatment of flour increased the hardness and chewiness of the steamed bread product, but other treatment showed opposite effect. Among the four ozone treatments, long duration of high-intensity treatment aroused the greatest change in pH, IPP, water molecular mobility of dough, and the quality of steamed bread, while short duration of low-intensity treatment had the minimum effect. Long duration of low-intensity treatment was close to the short duration of high-intensity treatment in quality attributes of wheat flour and the total ozone yield. These results suggested that the quality of wheat flour gradually changed with the increase of total ozone yield, and overozonization would greatly deteriorate the quality of wheat flour.