| The contamination of 3-monochloropropane-1,2-diol fatty acid esters (3-MCPDE) and glycidyl ester (GE) in 74 batches of 12 kinds of commercially available edible oils was evaluated,and the effect of deodorization conditions on the generation of 3-MCPDE and GE, as well as the effect of adsorbent and molecular distillation on the removal of 3-MCPDE and GE were studied.The results showed that the detection rates of 3-MCPDE and GE in the 12 kinds of oils were 100%, in which the 3-MCPDE content was 0.234 -12.212 mg/kg,and the GE content was 0.196-10.891 mg/kg. The highest content of 3-MCPDE and GE was found in rice bran oil, followed by palm olein. Deodorization temperature had a significant effect on 3-MCPDE and GE. The deodorization temperatures for large generation of 3-MCPDE and GE were > 220 ℃ and>200 ℃, respectively. As the deodorization time prolonging, the contents of 3-MCPDE and GE increased. GE could be easily removed by activated carbon, activated clay, silica gel and attapulgite with the removal rate all above 96%. However, 3-MCPDE was difficult to be removed by adsorbents. Molecular distillation could simultaneously remove 3-MCPDE and GE, and the removal rates of 3-MCPDE and GE reached 88% and 94% respectively at 230 ℃. |
