美拉德反应可显著改善大豆分离蛋白（SPI）的功能性质，本文研究了干热条件下SPI与核糖发生美拉德反应的可能性，即将SPI和核糖粉末直接混合后，以290 nm下的吸光度值和色度值L为指标，研究反应温度、混合比例、相对湿度及反应时间对两者美拉德反应的影响，并对美拉德反应产物的热性能和流变学性质进行了表征。结果表明，在干热条件下SPI与核糖极易发生美拉德反应，且最适条件为反应温度80 ℃、SPI：核糖混合比例1:1（m/m）、相对湿度26.10%和反应时间6 h。DSC分析表明SPI和核糖通过美拉德反应产生了易分解的中间产物，流变学研究则说明生成了大分子产物，使得美拉德反应产物在溶液中的黏度显著增加、弹性特征明显增强。由于干热法与广泛使用的湿热法相比工艺更加简单可行，因此在SPI的改性中具有很强的实际应用价值。

The Maillard reaction has been reported to be capable of improving the functional properties of soybean protein isolate (SPI). This work attempted to explore the possibility of the Maillard reaction between SPI and ribose under the dry heating circumstance, and the effects of temperature, SPI/ribose mixing ratio, relative humidity, and reaction duration were investigated in terms of absorbance at 290 nm and L values. In addition, thermal behavior and rheological properties of the resultant products of the Maillard reaction were characterized as well. The results indicated that the reaction occurred readily using dry heat and the optimum conditions were: temperature 80 ℃, SPI to ribose ratio 1:1 (m/m), relative humidity 26.10% and reaction duration 6 h. Differential scanning calorimetry (DSC) analyses confirmed that labile intermediates were produced during the reaction. Furthermore, rheological measurements indicated that the reaction endowed the products with enhanced elastic properties and increased viscosity, implying the formation of high-molecular weight products. Compared with the widely used wet heating method, the dry heating method was simpler and more feasible, thus showing great potential for modification of SPI.

国家自然基金资助项目（31101319）；青岛农业大学校高层次人才启动基金（631415）