卫生研究

目的建立体外模拟胃肠液消化稳定性试验和热稳定性试验方法,确定试验中的阳性和阴性参考蛋白质。方法在体外模拟胃肠液消化环境和热加工处理环境,通过SDS-PAGE凝胶电泳研究常见食物致敏原(鸡卵清蛋白OVA、牛β-乳球蛋白β-LG)、不常见食物致敏原(牛血清白蛋白BSA)和非致敏原(大豆脂肪水解酶LPE、马铃薯酸性磷酸酶PAP)在其中各观察时间点的降解情况。结果OVA在模拟胃肠液中60min不降解;β-LG在模拟胃液中60min不降解稳定存在,但在模拟肠液中30min内完全降解;BSA在模拟胃液中30min内完全降解,在模拟肠液中60min部分降解;PAP在模拟胃液中15s即完全降解,LPE在30s内完全降解;而在模拟肠液中,PAP60min完全不降解,LPE60min大部分降解。在热稳定性试验中,OVA、β-LG、BSA60min内不降解,PAP60min内完全降解。结论模拟胃液消化稳定性和热稳定性试验中设OVA为常见致敏原对照、BSA为不常见致敏原对照、PAP为非致敏原对照,模拟肠液消化稳定性试验中设OVA为常见致敏原对照、BSA为不常见致敏原对照、LPE为非致敏原对照。并据此初步建立体外消化稳定性和热稳定性试验方法。

Objective To establish the in vitro evaluation method in vitro on digestive stability and heat stability of food proteins and ascertain the reference proteins of each test.Methods With SDS-PAGE method,digestive stability of five food proteins with known allergenicity was assessed in vitro in simulated gastric and intestinal fluid and heat stability of them was determined by heat treatment.Results OVA and β-LG were stable within 60 min in SGF(simulated gastric fluid). β-LG was digested within 30min in SIF (simulated intestinal fluid). BSA was digested within 30min in SGF and partly digested within 60min in SIF. In SGF,PAP was digested within 15s and LPE within 30s. But in SIF,PAP was stable within 60min and most LPE was digested within 60min. Heat-treated OVA,β-LG and BSA were stable within 60min while PAP was totally disappeared within 60min.Conclusion The methods established in this study can be applied to evaluate the digestive stability and heat stability of food proteins.