Production of low-gizzerosine fish meal

吉泽罗辛是一种由过热的鱼粉引起的鸡胆侵蚀的致病化合物。Gizzerosine不含在新鲜鱼肉中，但在鱼肉加工过程中产生。如果产品被强烈加热，例如130ﾟC，3小时，鱼粉中会产生大量的吉兹罗辛。本研究旨在开发低Gizzerosine鱼粉的生产方法。首先，建立了一种简单的测定Gizzerosine的方法。在鱼粉中加入赖氨酸或抗坏血酸(0.5%)，在130ﾟ℃下加热3小时，可完成鱼粉样品的精制。在对照餐中产生了大量的吉兹罗辛。然而，添加0.5%赖氨酸的膳食中吉兹罗辛的含量较低。在鱼粉中添加赖氨酸的方法在实际鱼粉生产中得到了应用。使用该产品(添加0.3%或0.5%游离赖氨酸的鱼粉)，进行雏鸡生长试验、肌胃侵蚀发生率和生物赖氨酸利用率的研究。结果表明，即使在强热处理后，添加游离赖氨酸的鱼粉也远好于对照鱼粉，从动物的胃壁腐蚀率和生长速度来判断。该产品的赖氨酸利用率也很高。热处理后游离赖氨酸鱼粉的吉兹罗辛含量显著低于对照鱼粉，为生产低吉兹罗辛鱼粉提供了可能。

Gizzerosine is a causative compound of chicken gizzard erosion induced by over-heated fish meals. Gizzerosine is not contained in fresh fish meat but is produced during processing of fish meat. If the product is heated strongly, e.g. 130ﾟC, 3 hours, significant amount of gizzerosine is produced in the fish meal. The present studies were planned to develop methods to produced low-gizzerosine fish meal.At first, a simple method of gizzerosine determination was developed. The new method, which employs ion-exchange high performance liquid chromatography, could finish mare samples compared with the former methods.We added lysine or ascorbic acid (at 0.5 %) to a fish meal and heated the product at 130ﾟC, 3 hours. A significant amount of gizzerosine was produced in the control meal. However, the meal with 0.5 % lysine contained lower amount of gizzerosine. Addition of ascorbic acid induced bad effects, producing more gizzerosine.The method to add lysine to fish meal was applied for practical fish meal production. Employing the product (fish meals with 0.3 or 0.5 % free lysine), chick growth test, the incidence of gizzard erosion, and biological lysine availability were investigated. The results clearly showed that the fish meals with free lysine are far better than the control meals even after strong heat treatment, judged by the incidence of gizzard erosion and the growth rate of animals. The lysine availability in the product was also excellent. Gizzerosine content of the meals with free lysine was significantly lower than the control meals after heat treatment.The present project made it possible to produce low-gizzerosine fish meal.