| 摘要: | 本研究以加拿大黃豆為原料，研究內容主要區分兩大部分：﹙1﹚浸漬溫度、磨漿溫度及加熱方式對豆漿蛋白質及豆漿品質之影響；﹙2﹚浸漬溫度、磨漿溫度及加熱方式對盒裝豆腐質地之影響。
研究結果：﹙1﹚以5℃、30℃、60℃、80℃磨漿發現，隨著磨漿溫度升高，所得豆漿顏色較偏黃偏綠。低溫磨漿所得之豆漿黏度、顏色明亮度、白度指數均較高。不同溫度浸漬、磨漿及不同加熱方式對豆漿蛋白質表面疏水性的影響則是隨著磨漿溫度升高，其蛋白質表面疏水性也越高，浸漬溫度則是以5℃浸漬高於30℃，加熱方式則是以兩段式加熱方式其疏水性高於一段加熱。
另外，以SDS-PAGE電泳圖譜分析，7S球蛋白次單元體含量分佈隨著磨漿溫度越高有增加的趨勢，而11S球蛋白其酸性、鹼性次單元體則隨著磨漿溫度升高有減少的趨勢，11S/7S的比值隨著磨漿溫度升高而降低。﹙2﹚以不同溫度浸漬、磨漿及加熱方式製作之豆腐其離水率會隨著磨漿溫度升高而增加，浸漬溫度之離水率則是以30℃浸漬高於5℃浸漬。加熱方式則以兩段加熱高於一段加熱。以此條件製得之盒裝豆腐其密度影響則是，兩段加熱製作之豆腐其密度高於一段加熱。以低溫浸漬、低溫磨漿、兩段式加熱其豆腐成品性質硬度、凝膠性、附著性、彈性、咀嚼性及內聚性均會提高。本實驗結果可供黃豆加工業者加工條件控制及改善品質之參考。
This research used soybean from Canada as raw material and focusing on two major categories: (1)Effects of different soaking, grinding temperature and heating methods on soy milk protein and soy milk quality; (2)Effects of different soaking, grinding temperature and different heating methods on tofu texture.
Results showed: (1)Using different grinding temperature (5℃、30℃、60℃、80℃), as grinding temperature increased, the soymilk would become more yellowish and greenish. At lower grinding temperature, the soymilk viscosity, color brightness, and white index were higher. The protein surface hydrophobicity increased as the grinding temperature increased. The soaking temperature at 5℃ had higher protein surface hydrophobicity than at 30℃. Two-step heating had higher protein surface hydrophobicity than one-step heating.
Using SDS-PAGE electrophoresis pattern analysis, as the grinding temperature increased, the amount of β-conglycin subunit would increase. But the acidic and basic subunit of Glycinin and the ratio of 11S/7S would decrease. (2) Using different heating, soaking and grinding condition, the syneresis rate increased as grinding temperature increase. Soaking temperature at 30 ℃ or two-step heating had higher syneresis rate than soaking at 5 ℃ or one-step heating in respect. Two-step heating had higher density than one-step heating. Using lower soaking and grinding temperature and two-step heating would increase the tofu hardness, gumminess, adhesiveness, springiness, chewiness and cohesiveness. The results of this experiment could be used to improve the tofu quality for soy processing manufacturer. |
