| Conjugated linoleic acid (CLA) was prepared from safflower seed oil by alkali isomerization method. With conversion rate of CLA and content of non-active isomers as response values, reaction temperature, reaction time and alkali dosage of the isomerization were optimized by response surface methodology. The results showed that the optimal isomerization conditions were obtained as follows: reaction temperature 167 ℃，reaction time 6 h, alkali dosage 0.5 times of the mass of safflower seed oil; under these conditions, the conversion rate of CLA reached 97.9% and the content of non-active isomers was about 2%. The composition of the prepared CLA fatty acids mixture was analyzed by GC-MS, and the results indicated that the content of total CLA in the product was 77.31%, in which the contents of the two kinds of isomers 9c, 11t-CLA and 10t,12c-CLA, palmitic acid, stearic acid, oleic acid, linoleic acid and other trace components were 75.30%, 4.00%, 1.40%, 10.10%, 1.63% and 5.56%,respectively. |
