Abstract:Compared with buckwheat wantuo that were not quick-frozen, the quality of quick-frozen buckwheat wantuo, thawed using different methods was investigated. Four thawing methods were compared, namely natural air, microwave, atmospheric pressure cooker, and ultrasonic thawing. The results showed that the microwave method required 53 s, which was the shortest thawing time among the four methods. In terms of texture, the estimates for hardness, gumminess, and chewiness of quick-frozen buckwheat wantuo using microwave thawing were 1923 g, 1636 g, and 1548 g, respectively, which were the closest to those of the control. Natural air-thawing and ultrasonic thawing showed relatively high levels of hardness, with low levels of chewiness. The sensory scores of the sample using microwave thawing and the control were 81.20 and 81.00, respectively, with no significant difference (p > 0.05). In terms of color, the ΔE* values with microwave thawing and atmospheric pressure-cooker thawing methods were less than 2, while their individual effects on the color of quick-frozen buckwheat wantuo could not be distinguished by the naked eye. The rate of water loss with microwave method was 2.23%, which was the closest to that observed with the control method. Microwave thawing showed the lowest bacterial countsof 278 CFU/g, among all four thawing methods. As compared to the control, all four methods showed an impact on volatile flavor. This study demonstrated that microwave thawing was the most suitable method to thaw quick-frozen buckwheat wantuo.
