Mercer A, Castle L, Comyn J, Gilbert J
Ministry of Agriculture, Fisheries and Food, Food Science Laboratory, Norwich, U.K.
Food Addit Contam. 1990 Jul-Aug;7(4):497-507. doi: 10.1080/02652039009373911.
The diffusion coefficient of the plasticizer di-(2-ethylhexyl)adipate (DEHA) in Cheddar cheese (Df) was determined by measuring the extent to which DEHA penetrated cheese that was placed in intimate contact with artificially DEHA-contaminated cheese. Slices (20 microns) of cheese from the boundary layer, into which DEHA had migrated, were microtomed at -40 degrees C, and analyzed for DEHA by gas chromatography (GC). Mean values of Df determined by graph fitting experimental and calculated data were 1.5 x 10(-9) cm2 s-1 at 5 degrees C and 3.0 x 10(-8) cm2 s-1 at 25 degrees C. The partition coefficient (K) of DEHA between cheese and PVC film was derived from the partition coefficients of DEHA between acetonitrile (ACN) and cheese lipid, ACN and cheese solid, and ACN and PVC film. The mean values of K between cheese and PVC film were estimated to be 0.70 at 5 degrees C and 0.58 at 25 degrees C. The estimated values of Df and K were then used in a mathematical model (Till et al. 1982) to predict migration levels of DEHA into cheese. Good agreement with previously published experimental data was obtained. Extrapolation of the prediction of DEHA migration into fatty foods, such as salami and avocado, was also successful (ratio of experimental to predicted results within a factor of two). The values of Df and K for cheese are, however, inappropriate for modelling non-fatty foods such as meat, cakes, fruit and vegetables. Predicted values for these foods were typically 3-10-fold too high. More accurate predictions would probably be obtained if values of Df more relevant to these foods are used. The predictions were relatively insensitive to the value of K.
通过测量己二酸二（2-乙基己基）酯（DEHA）渗透到与人工DEHA污染奶酪紧密接触的切达干酪中的程度，测定了增塑剂己二酸二（2-乙基己基）酯（DEHA）在切达干酪中的扩散系数（Df）。从DEHA迁移进入的边界层切取20微米厚的干酪切片，在-40℃下进行切片，并用气相色谱法（GC）分析DEHA。通过对实验数据和计算数据进行曲线拟合确定的Df平均值在5℃时为1.5×10⁻⁹ cm² s⁻¹，在25℃时为3.0×10⁻⁸ cm² s⁻¹。DEHA在干酪和PVC膜之间的分配系数（K）由DEHA在乙腈（ACN）与干酪脂质、ACN与干酪固体以及ACN与PVC膜之间的分配系数推导得出。干酪和PVC膜之间K的平均值在5℃时估计为0.70，在25℃时为0.58。然后将估计的Df和K值用于数学模型（Till等人，1982年）中，以预测DEHA向干酪中的迁移水平。与先前发表的实验数据取得了良好的一致性。对DEHA向脂肪类食品（如意大利腊肠和鳄梨）中的迁移预测进行外推也取得了成功（实验结果与预测结果的比值在两倍以内）。然而，干酪的Df和K值不适用于对非脂肪类食品（如肉类、蛋糕、水果和蔬菜）进行建模。这些食品的预测值通常高出3至10倍。如果使用与这些食品更相关的Df值，可能会得到更准确的预测。预测对K值相对不敏感。
