花生粕脂肪含量对豆腐品质的影响

Effects of Oil Contents of Peanut Cakes on Tofu Quality

为了确定适用于制备花生豆腐的原料的脂肪含量,以低温花生粕为原料,采用谷氨酰胺转氨酶(transglutaminase,TG)和高温微压煮浆(high-temperature pressure cooking,HTPC)工艺制备花生豆腐,研究不同花生粕脂肪含量(6.89%、10.12%、15.43%、20.28%和25.54%)对豆腐质构的影响,对比花生豆腐与市售大豆豆腐的耐煮性和色泽,并分析加工过程中花生蛋白的结构变化。结果表明,花生粕脂肪含量对豆腐质构有显著影响(P<0.05),除脂肪含量为25.54%的花生粕外,其他脂肪含量的花生粕均可用于制备花生豆腐。当花生粕脂肪含量为6.89%时,可制得与市售大豆石膏豆腐的质构、耐煮性相当的花生豆腐产品,且其黄度值b(8.38)显著小于大豆石膏(15.86)和卤水(16.56)豆腐(P<0.05),具有色泽优势。而对于花生蛋白结构变化的分析表明,当花生粕脂肪含量相对较低(6.89%~20.28%)时,TG对花生蛋白的作用效果较好,进一步施加HTPC处理可使花生蛋白完全变性,并且通过形成疏水相互作用和二硫键以维持豆腐凝胶结构。研究结果为花生豆腐的加工提供了技术指导和理论支撑。

In order to determine the suitable oil content of raw material for peanut tofu preparation,peanut tofu was produced by the method combining transglutaminase（ TG） and high-temperature pressure cooking（ HTPC）,using low-temperature peanut cakes（ LTPC） as the raw material. The effects of different oil contents（ 6.89%,10.12%,15.43%,20.28% and 25. 54%） of peanut cakes on the tofu texture were studied,the color and cooking loss of the peanut tofu were compared with the commercial soybean tofu,and the structural changes of peanut proteins during tofu processing were also analyzed. The results showed that the tofu texture was significantly influenced by the oil content of the LTPC（ P 0. 05）,and the peanut tofu could be made from the LTPC with oil contents from 6.89% to 20.28%. When the oil content of the LTPC was 6.89%,the texture and cooking loss of the obtained peanut tofu were close to those of the commercial soybean gypsum tofu,and its degree of yellow value b（ 8. 38） was significantly lower than that of the soybean gypsum（ 15.86） and bitter（ 16.56） tofu（ P0.05）,which might be more accepted by the consumers. Besides,the analysis on the structural changes of peanut proteins showed that TG had good effect on peanut proteins,when the oil contents of LTPC were low（ 6.89% ~ 20.28%）,then the peanut proteins could be completely denatured after subsequent HTPC treatment,and finally hydrophobic interaction and disulfide bonds were formed to stabilize the gel structure of peanut tofu. This study provided technical guidance and theoretical support for peanut tofu processing.