胡萝卜抗冻蛋白对亚冻结下冻融面团品质的影响

为了探究胡萝卜抗冻蛋白（Carrot Antifreeze Proteins,CaAFPs）对不同冻融循环下面团性质的影响，该研究将CaAFPs按照0.5%的比例添加到面团中，并以未加入CaAFPs的面团作为对照。通过比较4 ℃冷藏、-12 ℃亚冻结冻藏以及-18 ℃冻藏下3种储藏温度下，以冻融处理为辅助手段，测定不同条件下面团的含水率、失水率、可冻结水含量、质构特性以及pH值等指标的变化趋势，以此来研究CaAFPs对冻融下亚冻结面团性质的影响及机理。结果表明：经过5次冻融循环后，对照组面团的失水率呈现不同程度的上升趋势（P<0.05），加入CaAFPs后，有助于延缓面团水分的散失，各组失水率均有所下降。对照组含水率呈现不同程度下降趋势（P<0.05），加入CaAFPs后，含水率较对照组高（P<0.05）。对照组面团的可冻结水含量呈现不同程度的上升趋势（P<0.05），加入CaAFPs后，对面团的网络结构有一定的保护作用，可冻结水含量均有所下降。对照组硬度、胶着性呈现上升趋势（P<0.05），弹性、黏聚性和咀嚼性呈现下降趋势（P<0.05），加入CaAFPs后，在一定程度上可以改善面团的质构特性，使得质构变化缓慢些。对照组面团的pH值呈现不同程度下降趋势（P<0.05），加入CaAFPs后，可以延缓面团酸化现象，面团的pH变化趋势变小。以上说明添加CaAFPs对冻融面团品质具有一定的保护作用。研究结果为CaAFPs在冷冻面团中的应用以及优化冷冻储藏温度等提供一定的参考，面团在亚冻结冻藏-12 ℃下能够保持较好的性质，故可考虑将面团储藏在-12 ℃下以节约能源消耗并能保持其较佳的状态，同时也拓宽了在亚冻结状态下研究抗冻蛋白的性质的研究思路。

Effects of carrot antifreeze protein on the quality of freeze-thaw dough under subfreezing

Carrot Antifreeze Proteins (CaAFPs) are characterized by the unique anti-recrystallization capacity for potential uses in the food industry. In this study, a systematic investigation was conducted to explore the effect of CaAFPs on the properties of subfrozen dough under different freeze-thaw cycles, in order to determine if -12 ℃ suitable for the frozen dough storage and the state. The CaAFPs were added to the dough at a proportion of 0.5%. The dough without CaAFPs was used as the control. Three kinds of storage temperatures were set as 4℃ refrigerated, -12 ℃ subfrozen, and -18 ℃ frozen. The freeze-thaw was taken as the auxiliary means to measure the freezable water content, texture, and pH under the different conditions of moisture content and water loss rate. Significance analysis was then made to compare the freeze-thaw CaAFPs under the influence mechanism of the frozen dough properties. The results showed that the water loss rate of the dough in the control group showed an increasing trend in the different degrees (P<0.05) after five freeze-thaw cycles. The addition of CaAFPs greatly contributed to delaying the water loss of the dough, indicating a decrease in the water loss rate in all groups. The water content of the control group showed a decreasing trend in the different degrees (P<0.05). The water content was higher than that of the control group after adding CaAFPs (P<0.05) under freeze-thaw. An increasing trend was found in the freezable water content of the dough in the control group in the different degrees (P<0.05) under freeze-thaw. The addition of CaAFPs posed a certain protective effect on the network structure of the dough, indicating the decrease in the freezable water content. There was an upward trend (P<0.05) for the hardness and gumminess in the control group, whereas, a downward trend was the springing, cohesiveness, and chewiness (P<0.05) under freeze-thaw. After adding CaAFPs, the texture characteristics of the dough were improved significantly to more slowly adjust the texture. The pH of the dough showed a decreasing trend in the different degrees (P<0.05) in the control group. The acidification of dough was delayed for the smaller pH change trend of dough, when adding CaAFPs. In general, the moisture content of dough decreased with the increase of freeze-thaw time, where the water loss rate and the content of freezable water increased significantly, the pH value decreased, and the texture was difficult to say. But the opposite trend occurred, as the temperature dropped. Among them, -12 ℃ and -18 ℃ were significantly better than 4 ℃. There was no significant difference between them in the first two times of freeze-thaw, but after three times of freeze-thaw, -18 ℃ was obviously better than -12 ℃. The findings can provide a strong reference for the application of CaAFPs in the frozen dough and the optimization of freezing storage temperature. As such, the dough can be maintained excellent properties at -12 ℃ in the sub-freezing storage. Therefore, the dough can be expected to store at -12 ℃ for energy saving under the better state. At the same time, a new research idea can be offered for the properties of antifreeze proteins in the subfreezing state.