纳豆几种干燥方法的比较及主要营养成分的分析

Analysis and Comparison of Several Natto Drying Methods and Major Nutrients

延长纳豆的保藏时间,能更有效地发挥其价值。固态发酵的纳豆为原料,比较3种干燥方式对纳豆激酶活性的影响,分析干燥后的纳豆粉的营养成分。结果表明,真空冷冻干燥在10~15 h,纳豆激酶活性损失率小于17%;热风干燥在50℃~60℃条件下干燥16~32 h时纳豆激酶活性损失率28%~43%,水分含量控制在10%内;冷风干燥在24℃~28℃条件下干燥48~72 h时纳豆激酶活性损失率在46%~51%,水分含量控制在12%~8%;因此,热风干燥更适合工业化生产。干燥后的纳豆粉的蛋白质、还原糖含量比原料大豆粉高,膳食纤维含量高达18%,总氨基酸含量为32.08g/100 g,必须氨基酸含量为11.12 g/100 g。

Extending the natto preservation time, can play nutritional value of natto more effectively. Natto of solid state fermentation as raw materials, study the influence of three drying methods on natto kinase activity, and analyze the nutritional content of dried natto flour. The results showed that vacuum freeze-drying for 10~15 h, natto kinase activity loss rate was less than 17%; Hot air drying at 50 ℃~60 ℃ for 16~32 h natto kinase activity was loss rate 28%~43%, and moisture content controlled below 10%; When cold air dried at 24 ℃~28 ℃ for 48~72 h, natto kinase activity loss rate was 46%~51%, and moisture content controlled at 12%~8%. It was concluded that hot air drying was more suitable for industrial production. The protein content and reducing sugar content of dried natto flour were higher than that of soy flour; The dietary fiber content of dried natto flour was up to 18%; The total amino acid content was 32.08 g/100 g, and essential amino acid content was 11.12 g/100 g.