摩擦行为对食品接触用不锈钢制品中金属元素迁移影响研究

The effect of friction behavior on the migration of metal elements from stainless-steel articles for food contact

目的评价摩擦行为对食品接触用不锈钢制品中金属元素迁移的影响。方法分别采用GB 4806.9-2016《食品安全国家标准食品接触用金属材料及制品》和欧洲委员会决议CM/Res(2013)9(以下简称欧标)规定方法,检测长期使用过和市售新不锈钢制品中金属元素的迁移水平,迁移试验条件分别为4%乙酸中煮沸30 min后室温放置24 h和5 g/L柠檬酸中100℃下浸泡2 h。参考GB/T 32095.2-2015《家用食品金属烹饪器具不粘表面性能及测试规范第2部分:不粘性及耐磨性测试规范》振动耐磨方法,研究动态摩擦对市售新不锈钢制品中金属元素迁移的影响,以上方法金属迁移量均符合相应标准要求。结果采用欧标方法,5份长期使用摩擦后不锈钢制品铅(Pb)第1次迁移量高于定量限,而全新不锈钢制品均低于定量限。采用国标方法,80%(4/5)长期使用摩擦后不锈钢制品的第1次迁移试验中铬(Cr)的迁移量超过定量限,远高于全新不锈钢制品(20%,1/5)。3次动态摩擦试验后Cr和镍(Ni)迁移达到平衡。结论国标的迁移试验体系比欧标对不锈钢中Cr元素提取能力强。摩擦行为促进不锈钢的腐蚀和金属元素迁移,长期使用后的不锈钢制品与全新制品比较,Pd和Cr元素的迁移水平更高,但均不存在安全风险。

Objective To evaluate the effect of friction behavior on migration levels of metal elements from stainless-steel articles for food contact.Methods The migration levels of metal elements from used and new stainless-steel articles were compared according to GB 4806.9-2016 and Council of Europe Resolution CM/Res(2013)9.The migration conditions were boiling in 4%acetic acid for 30 min followed by at room temperature for 24 h and soaking in 5 g/L citric acid at 100℃for 2 h,respectively.Meanwhile,the impact of dynamic friction on migration were investigated on new stainless-steel articles,where the friction method were referred to the GB/T 32095.2-2015 standard.Migration of metal elements complied with the corresponding standard.Results Based on the European standard,migration of lead in the first migration test was above limit of quantitation(LOQ)in all five used stainless-steel articles after friction,but none in new ones.The quantification rate of chromium in the first migration test in 80%(4/5)of used stainless-steel articles were above LOQ after friction by GB 4806.9-2016 standard while were 20%(1/5)in new ones.The migration level of Cr was higher by GB 4806.9-2016 standard than by European resolution in single dynamic friction study.Results from the dynamic friction experiments indicated that the migration of Cr and Ni reached equilibrium after 3 times of friction.Conclusion The migration condition in GB 4806.9-2016 standard had stronger leaching ability for Cr from stainless-steel articles than that in European resolution.Friction behavior promoted corrosion and metal element migration of stainless steel.Long-term used stainless-steel products had higher lead and chromium migration than new products,but without safety risks.