豆乳加熱速率與凝固劑濃度對豆腐品質影響之研究

Study on the effect in the quality of tofu for the heating rate of soymilk and concentration of coagulant addition

連振昌(Cheng-Chang Lien) ； 沈裕傑(Yu-Jie Shen) ； 黃膺任(Ying-Jen Huang)

《農林學報》 65卷1期 (2017/06) Pp. 43-50

https://doi.org/10.30089/JAF.201706_65(1).0005

摘要

豆腐製程中，豆乳加熱速率與溫度以及凝固劑濃度與添加時機是決定豆腐品質的重要因子，本研究在直流歐姆加熱的溫度控制下，探討上述二種控制變數與豆腐品質關聯性，豆乳凝固後進行擠壓得到豆腐成品，豆腐品質採用乳清導電度與穿刺試驗進行評量，研究結果顯示，乳清導電度隨加熱速率及凝固劑濃度成正比，在0.062 ℃/s的加熱速率下，豆腐的硬度、脆度與彈性都較低，而1.0% GDL凝固劑濃度較0.5%及1.5%濃度有較高的硬度、脆度與彈性指標值。

關鍵字

加熱速度 ； 凝固劑濃度 ； 豆腐 ； 導電度 ； 歐姆加熱

並列摘要

In tofu making by heat treatment, the heating rate and final temperature of whey, and the timing and concentration of coagulant addition are the two most dominant factors. This study explores the correlation of tofu quality with the above two factors under direct-current ohmic heating. Tofu product is obtained by pressing coagulating tofu curd. The quality of tofu product is assessed with electrical conductivity of whey residue and penetrometer measurements. The results show that the electrical conductivity is proportional to heating rate and concentration of coagulant addition. Tofu product from the heating rate of 0.062℃/s has lower crispness, hardness, and elasticity. The three indices are the largest at gelation under 1.0% GDL in comparison with gelations under 0.5% and 1.5% GDL.

並列關鍵字

Heating rate ； Concentration of coagulant addition ； Tofu ； Conductivity ； Ohmic heating