Studies on mechanism by which zinc protoporphyrin IX is formed in meat product and its applications

我们本研究的目的是阐明锌原卟啉 IX (ZPP) 在不添加亚硝酸盐或硝酸盐的肉制品中的作用机制，并利用 ZPP 改善肉制品的颜色。原卟啉IX（PPIX）不与金属离子配位，是由血红素生物合成途径和血红素形成的。似乎一氧化氮（NO）抑制PPIX的形成，从而抑制ZPP的形成。肉类中的水溶性成分和水不溶性成分对于ZPP的形成至关重要。水溶性成分似乎不是含血红素的肌红蛋白。帕尔玛火腿中的水溶性 ZPP 可以通过凝胶色谱以单峰形式分离出来。有人建议ZPP 与糖酵解酶结合。尽管将形成大量ZPP的猪肝添加到煮熟的香肠中，但颜色并没有因肝颜色而改善。对于萨拉米香肠、生香肠来说，肝脏的添加和pH值的调节（5.5）增加了ZPP含量，改善了萨拉米香肠的色泽。模型实验中ZPP的形成量随酸化剂的不同而变化。通过选择合适的酸化剂并调节pH值，肉制品中容易形成大量的ZPP，从而改善肉制品的色泽。

Our objectives in this study are to elucidate the mechanism by which zinc protoporphyrin IX (ZPP) in meat products with no addition of nitrite or nitrate and to improve the color of meat products by using ZPP. Protoporphyrin IX (PPIX), to which metal ion is not coordinated, was formed both from heme biosynthesis route and heme. It seems to be that nitric oxide (NO) inhibits the formation of PPIX and consequently inhibits the formation of ZPP. Water-soluble component(s) and water-insoluble component(s) in meat are essential for the formation of ZPP. The water-soluble component(s) seems not to be myoglobin with heme. Water-soluble ZPP in Parma ham could be separated as a single peak by using gel chromatography. It was suggested that ZPP is bound a glycolytic enzyme. Although pork liver in which a large amount of ZPP has been formed was added to cooked sausage, the color was not improved because of liver color. As to salami, raw sausage, the addition of liver and the adjustment of pH (5.5) increased ZPP content and improved the color of salami. The amount of ZPP formed in model experiment varied with acidifiers. By selecting proper acidifier and adjusting pH, a large amount of ZPP was likely to be formed in meat product, resulting in improvement of its color.