冻结温度对冷冻全麦馒头复蒸品质及组分性质的影响

Effect of Freezing Temperature on Re-steaming Quality and Component Properties of Frozen Whole Wheat Steamed Bread

分析不同冻结温度(-20、-40、-80℃)对不同全麦粉替代率(30%、50%、100%)冷冻全麦馒头复蒸品质及组分性质的影响,结果表明:冻结温度越低,冷冻速度越快,复蒸全麦馒头比容保持越好,对复蒸全麦馒头的质构品质影响越小。冻结温度对不同全麦粉替代率冷冻馒头的高径比无显著影响。-20℃下,不同全麦粉替代率冷冻馒头复蒸后硬度均显著高于新鲜馒头;-80℃下,复蒸后馒头硬度最接近新鲜馒头。冻结温度越低,冷冻全麦馒头淀粉的糊化焓值越低,100%全麦馒头淀粉糊化特性指标值越接近新鲜馒头;-40℃下,30%和50%全麦馒头淀粉糊化特性指标值与新鲜馒头更接近。较低的冻结温度下冷冻馒头中面筋蛋白的可萃取率较低,面筋蛋白二级结构破坏较小。冻结温度越低,全麦馒头内部的微观结构受损越小,复蒸后,其品质越接近新鲜馒头。综上,较低的冻结温度有利于保持全麦馒头较好的品质。

The effects of different freezing temperatures(-20℃,-40℃,-80℃)on the re-steaming quality and component properties of frozen whole wheat steamed bread with different whole wheat flour replacement rates(30%,50%,100%)were analyzed.The results showed that the specific volume retention of the re-steamed whole wheat steamed bread was higher and the texture quality of the re-steamed whole wheat steamed bread was better with the lower freezing temperature and the faster freezing speed.Freezing temperature had no significant effect on the height/diameter ratio of frozen steamed bread with different whole wheat flour replacement rate.At-20℃,the hardness of frozen steamed bread with different whole wheat flour replacement rate was significantly higher than that of fresh steamed bread after re-steaming.At-80℃,the hardness of steamed breads is similar to that of fresh steamed bread after re-steaming.With the decrease of freezing temperature,the starch gelatinization enthalpy of frozen whole wheat steamed bread was lower,and the index value of starch gelatinization characteristics of 100%frozen whole wheat steamed bread was similar to that of fresh steamed bread,30%and 50%whole wheat steamed bread were closer to that of fresh steamed buns at-40℃freezing temperature.The lower the extractability of gluten protein was in frozen steamed buns at lower freezing temperature,the smaller the damage of gluten protein structure was.The damage to the internal microstructure of whole wheat steamed buns was smaller at lower freezing temperature,and its quality was closer to that of fresh steamed buns.In short,the lower freezing temperature is conducive to keeping the better quality of whole wheat steamed buns.To provide basis and reference for frozen whole wheat steamed buns processing and quality improvement.