油脂微波加热模型中3-氯-1,2-丙二醇脂肪酸酯的形成

通过建立油脂微波加热模型，研究不同的油脂微波加热后3-氯-1,2-丙二醇（3-chloropropane-1,2-diol，3-MCPD）脂肪酸酯含量的变化情况以及NaCl溶液、pH值、时间、不连续微波和金属离子等因素对3-MCPD脂肪酸酯形成的影响。结果表明：1）熟榨植物油微波加热后3-MCPD脂肪酸酯含量增加均超过9 mg/kg，远超过其他植物油。2）3-MCPD脂肪酸酯含量随NaCl的质量浓度增加而增加，随NaCl溶液体积分数的增加呈先增加后减少趋势。3）酸性环境促进3-MCPD脂肪酸酯形成。4）微波加热10 min内，3-MCPD脂肪酸酯含量与时间呈正相关。5）微波总时间一定的情况下，不连续微波产生的3-MCPD脂肪酸酯明显少于连续微波。6）金属离子作为催化剂参与活性中间物的形成，能明显地促进3-MCPD脂肪酸酯的形成。上述结果可为食品微波加工处理过程中危害物3-MCPD脂肪酸酯的控制研究提供数据支持。

Formation of 3-Chloropropane-1,2-diol in Microwave Heating Model of Edible Oil

A series of experiments have been conducted to establish a model system through microwave heating to explore
the formation of 3-chloropropane-1,2-diol (3-MCPD) in edible oil as a function of oil type, NaCl, pH, heating time,
intermittent microwave heating and metal ions. The results showed that 1) microwave heating resulted in formation of over
9 mg/kg 3-MCPD in hot-pressed oils, whereas much less 3-MCPD was formed in cold-pressed oils and commercial oils; 2)
the amount of 3-MCPD esters increased with increasing concentration of sodium chloride solution, and increased firstly and
then decreased with increasing proportion of sodium chloride solution added, reaching maximum value at 20%; 3) acidic
condition could promote the formation of 3-MCPD; 4) the amount of 3-MCPD increased with increasing time up to 10
minutes; 5) compared to continuous microwave heating for an equal time, intermittent microwave heating could inhibit the
production of 3-MCPD; and 6) metal ions could significantly promote the formation of 3-MCPD esters because metal ions
could act as catalysts to promote the formation of intermediates during the formation of 3-MCPD. Therefore, this study can
be regarded as a data support for limiting the formation of 3-MCPD esters during microwave heating of foods.