针对欧盟法规(EU) 10/2011规定,测定食品接触材料(塑料器皿)的总迁移量时,需将塑料制品置于模拟液中于40 ℃浸泡10 d,检测周期过长的问题,试验了在几种不同的模拟液中改变浸泡温度及时间,以期达到缩短检测周期的目的。最终选择了以下几种浸泡条件:① 以乙醇-水(10+90)混合液作为模拟液,于100 ℃浸泡88 h;② 乙酸-水(3+97)溶液为模拟液,于100 ℃浸泡6 h;③ 乙醇-水(95+5)混合液为模拟液,在60 ℃浸泡40 h;④ 异辛烷为模拟液,于60 ℃浸泡5 h。浸泡结束后,将模拟液移入已称至恒重的蒸发皿(m1)中,蒸发至干,移入105 ℃烘箱中放置过夜并称至恒重(m2),根据m2与m1的差值(残渣量)除以浸泡体积即得总迁移量。采用上述改进的浸泡条件,不仅缩短了检测时间,而且能满足相关法规的要求。

As stipulated in the regulation of (EU) 10/2011, for determination of over-all migration from plastic wares intended to come into contact with food, the sample should be immersed in simulated liquor at 40 ℃ for 10 days. Aiming to shorten the testing time, conditions of immersion of different kinds of plastics in various simulated liquor under different temperatures with a shorter time were tested, and the following procedures were proposed: ① immerse in mixture of C2H5OH-H2O (10+90) at 100 ℃ for 88 h;② immerse in CH3COOH-H2O (3+97) at 100 ℃ for 6 h;③ immerse in C2H5OH-H2O (95+5) at 60 ℃ for 40 h;④ immerse in iso-octane at 60 ℃ for 5 h. At the end of immersion, the simulated liquor was removed to an evaporating dish (weighed to constant mass of m1 previously), and evaporated to dryness. The dish together with the residue was placed in an oven (at 105 ℃) overnight and its mass was weighed to constant (m2). Value of all-over migration was calculated by m2-m1/volume of simulated liquor. By using either of the 4 modified immersion conditions, not only the testing time was shortened, and the results were also found to meet with the requirements of the relative regulations.