冰提苜蓿冰结构蛋白及其对冷冻面团的影响

Extraction of Alfalfa Ice Structuring Proteins Using Ice and Their Effect on Frozen Dough

摘要:

以紫花苜蓿草粉为原料，采用冰结合磷酸盐缓冲溶液法提取苜蓿冰结构蛋白。通过对苜蓿冰结构蛋白提取率的计算，对提取过程中的pH值、缓冲溶液的浓度、料液质量体积比进行优化。经单因素实验及响应曲面实验得到提取苜蓿冰洁构蛋白的最佳工艺参数为：料液质量体积比为1 g∶20 mL，缓冲液pH 8.0，磷酸盐缓冲液浓度为61 mmol/L，其最终提取率可达到 2.87%。利用生物显微镜对苜蓿冰结构蛋白的冰晶形态进行观察，可以观测到许多体积小、且呈现六棱型及多边型的不规则形状，说明其对冰晶生长及冰晶形态的抑制与修饰效果显著，具有很好的抗冻活性。利用SDS-PAGE对苜蓿冰洁构蛋白进行检测，确定其蛋白质相对分子质量约为52 000，苜蓿冰结构蛋白应用到冷冻面团中发现可改善面团的品质。

Abstract:

In this study，ice structuring proteins were extracted from the Alfalfa meal powder using ice of Alfalfa were optimized by calculation of extraction efficiency，single-factor experiment and response extraction with phosphote buffer solution Furthermore，the extraction conditions for ice structuring proteins surface methodology. The results revealed that the extraction yield of Alfalfa ice structuring proteins was up to 2.87%，when the extraction was carried out by suspending in 61 mmol/L phosphate buffer solution at pH 8.0 with a solid/liquid ratio of 1∶20 and 46 ice pieces were added in per 100 milliliters of crude extracts. Additionally，the observed ice crystal morphology suggested that the ice structuring proteins of Alfalfa which mostly showed six hexagons or irregular shapes were small in size，indicating that ice structuring proteins of Alfalfa are able to modify the conformations of ice crystals and significantly inhibit the growth. the protein molecular weight of Alfalfa ice structuring proteins is about for 52 kDa，which was by SDS-PAGE.