不同培养条件对红曲鲜榨米色价的影响

Effect of Different Culture Conditions on Color Value of Red Yeast Fresh Extruded Rice

目的针对鲜榨米易氧化、吸潮的问题,使用红曲对鲜榨米进行发酵,制备红曲鲜榨米,开发鲜榨米新产品,分析不同培养条件对红曲鲜榨米色价的影响。方法以鲜榨米为固态培养基质,利用传统固态发酵的方式,制备红曲鲜榨米,并分析培养温度、水添加量、pH值、外源氮含量和培养时间等培养条件对红曲鲜榨米色素色价的影响。结果红曲鲜榨米醇溶性色素色价明显高于水溶性色素;水分含量对色素积累的影响较小;在30℃时,醇溶性橙、黄、红色素的色价分别高达298.34,186.35,230.09 U/g;当pH值为4.0时,水溶性色素色价最高,当pH值为7.0时,醇溶性色素色价最高;当醇、水溶性色素色价最高时,外源氮的质量分数分别为0.9%,0.5%;在培养6 d时红曲鲜榨米醇溶性色素色价最高,在培养7 d时水溶性色素色值最高。结论外源氮含量、pH值和培养时间对红曲鲜榨米水溶性和醇溶性的影响较大。

The work aims to ferment the fresh extruded rice with red yeast to prepare red yeast fresh extruded rice and develop fresh extruded rice products and analyze the influence of different culture conditions on color value of red yeast fresh extruded rice,thus solving the problem of easy oxidation and moisture absorption of fresh extruded rice.The fresh extruded rice was used as the solid culture substrate to prepare the red yeast fresh extruded rice with traditional solid state fermentation method and analyze the influence of culture temperature,water amount,pH,content of exogenous nitrogen and culture time on the color value of pigment of red yeast fresh extruded rice.The color value of alcohol-soluble pigment in fresh rice was significantly higher than that of water-soluble pigment.Water content had little influence on pigment accumulation.At 30℃,the color values of alcohol-soluble orange,yellow and red pigments were as high as 298.34,186.35,230.09 U/g,respectively.Water-soluble pigments had the highest color value when pH=4.0,while alcohol-soluble pigments had the highest color value when pH=7.0.When the color value of alcohol and water-soluble pigment was the highest,the amount of exogenous nitrogen was 0.9%and 0.5%,respectively.Moreover,the color value of alcohol-soluble pigment in red yeast fresh extruded rice was the highest at 6 d,while the water-soluble pigment reached the highest at 7 d.Exogenous nitrogen content, pH value and culture time have great influence on water solubility and alcohol solubility ofred yeast fresh extruded rice.