3-MCPD- and glycidyl esters can be mitigated in vegetable oils by use of short path distillation

Short path distillation was applied to produce edible oils low in 3-MCPD-FE and G-FE, but with comparable quality to conventionally deodorized oils. By use of the Response Surface Methology the effect of different process parameters (condenser temperature (X-1), evaporator temperature (X-2), stirrer speed (X-3) and pump frequency (X-4)) on quality parameters of the oil (content of 3-MCPD-FE/G-FE (minimal), acid value (minimal), content of vitamin-E-active compounds (sum of tocopherols and tocotrienols, maximal) and oxidation stability (maximal)) was investigated. A model was calculated for the production of refined palm oil with lowest amounts of 3-MCPD-FE/G-FE and a chemical and sensory quality comparable to oil produced by standard deodorization. For the different variables of short path distillation no 3-MCPD-FE was detected in any of the samples, while the level for G-FE ranged between the limit of detection and 0.7 mg/kg. A target conflict between the content of vitamin-E-active compounds (maximal) and acid value (minimal) was found, but in a (global) optimum of all target quality parameters (condenser temperature = 60 degrees C, evaporator temperature = 170 degrees C, stirrer speed = 100 rpm and pump frequency = 20 Hz) the quality of the short path distilled palm oil was comparable to conventionally refined palm oil. Slightly poorer sensory quality regarding taste and smell can be improved by a mild deodorization after short path distillation. Only the colour of the resulting oil differs from that of a conventionally refined oil, one being orange red due to the carotinoids which were not thermally decomposed.