Zhu Yunping, Wang Yu, Li Jinlong, Li Fang, Teng Chao, Li Xiuting
Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU) , Beijing 100048, People's Republic of China.
Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University (BTBU) , Beijing 100048, People's Republic of China.
J Agric Food Chem. 2017 Jun 14;65(23):4728-4735. doi: 10.1021/acs.jafc.7b00837. Epub 2017 May 31.
This study investigated the effects of water-extractable arabinoxylan (WEAX) on gluten by thermal treatment. Fourier transform infrared spectroscopy (FTIR) results showed that heating significantly decreased β-sheets and β-turn structures in gluten proteins between 25 and 55 °C. The addition of WEAX caused a transition from β-turn to β-sheets at >55 °C. The ratio of weakly hydrogen-bonded β-sheets to strongly hydrogen-bonded β-sheets demonstrated an increasing trend with temperature increasing, but WEAX can hinder this process. FT-Raman results revealed that a hydrophilic environment was developed with 5% WEAX at 25 °C, and phenolic hydroxyl on ferulic acid can form new H-bonds with the phenyl groups of the nondissociated Tyr residues. A 5% WEAX content is helpful for gluten to maintain its original gauche-gauche-gauche conformation of disulfide bond upon heating. In addition, WEAX can reduce the elasticity of gluten and form a soft texture at 25, 55, and 75 °C.
本研究通过热处理研究了水可提取阿拉伯木聚糖（WEAX）对谷蛋白的影响。傅里叶变换红外光谱（FTIR）结果表明，加热显著降低了25至55°C之间谷蛋白中的β-折叠和β-转角结构。在>55°C时，添加WEAX导致从β-转角向β-折叠转变。随着温度升高，弱氢键结合的β-折叠与强氢键结合的β-折叠的比例呈增加趋势，但WEAX可阻碍这一过程。傅里叶变换拉曼光谱（FT-Raman）结果显示，在25°C下添加5%的WEAX可形成亲水环境，阿魏酸上的酚羟基可与未解离的酪氨酸残基的苯基形成新的氢键。5%的WEAX含量有助于谷蛋白在加热时保持其二硫键的原始左-左-左构象。此外，在25、55和75°C时，WEAX可降低谷蛋白的弹性并形成柔软质地。
