Provided are a method of concentrating protein in grain powder, grain powder including protein that has been concentrated by using the method, and a feed additive including the grain powder including concentrated protein. According to the method of concentrating protein in grain powder, grain powder is treated with enzyme to increase the water-soluble saccharide content in a source, and by inoculating bacteria or yeast and fermentation, the increased water-soluble saccharide is removed, leading to a higher concentration of protein. Thus, the protein content ratio increase effects and the function of grain powder as a protein source are enhanced.本發明提供一種穀物粉中濃縮蛋白質的方法、一種包含已藉由使用所述方法濃縮的蛋白質的穀物粉、以及一種包含含有濃縮蛋白質的所述穀物粉的飼料添加劑。根據所述穀物粉中濃縮蛋白質的方法,用酶處理穀物粉以增加料源中水溶性糖含量,並且藉由接種細菌或酵母並發酵,移除所增加的水溶性糖,從而得到更高的蛋白質濃度。因而,增強了作為蛋白質源的穀物粉的蛋白質含量比值增加效果以及功能。
