Optimization of functional diacylglycerol (DAG) oil Production from safflower oil and evaluation of its properties

From 1999 and 2000، DAG oil production has been started in Japan and USA. It must be mentioned that DAG oil has been considered as useful product for human health and it is known as functional and nutraceutical cooking oil. The objective of this study was to evaluate reaction parameters in DAG production from safflower oil and to optimize the process to obtain maximum yield of DAG. After safflower oil extraction، enzymatic glycerolysis was used to produce DAG oil. The treatments were determined using Design-expert software and after modeling، the process optimization was done. Finally، some physicochemical properties of DAG oil were investigated. After modeling، it was observed that the enzyme load had linear effect while the reaction temperature and glycerol content showed the quadratic effect on DAG yield. Also it was obtained that there was significant interaction effect between enzyme load/time، enzyme load/ glycerol and time/glycerol. Results showed that there was no significant difference between DAG and safflower oils in terms of specific gravity and iodine value but refractive index، color and peroxide value were different. Maximum production of DAG (48. 454 %) obtained at reaction temperature of 46. 9 ºC، reaction time of 4 h، enzyme load of 0. 75 % (weight of oil)، and molar ratio of glycerol to oil 2:1 which was increased to 53. 84 % after product purification.