Camel hump fat (CHF) is one of the animal fat and a kind of byproduct of the camel slaughterhouses which can be used in food industry. According to FDA it is possible to supply 30% of bulk energy from oils and fats; 10% from saturated and trans fatty acids, 10% from monounsaturated fatty acids and 10% from polyunsaturated fatty acids. Substitution of any kind of oils and fats with another can cause health problems. Nowadays unfortunately, animal fat sources have been eliminated from human diets while hydrogenated vegetable oils are used to supply saturated fatty acids. There are 50-60 % trans fatty acids in hydrogenated oils which cause an increase in LDL cholesterol whereas animal fats like camel hump fat are rich in saturated and mono unsaturated fatty acids so can be used in different foods. In the present work some physicochemical properties of CHF were determined. Its iodine index is 38/28 g I 2 /100g fat and represents its high saturated fatty acids. Saponification value (190/32 mg KOH/g fat) indicates that most of its fatty acids are long chain. Low peroxide index of CHF (0/33 meq/Kg) can show its high oxidation stability. Its low acidic value (0/49) is due to low existence of free fatty acids in the fat. High melting point of CHF that cause its solid form at room temperature is due to its saturated long chain fatty acids. Specific gravity and refractive index of this fat at 60 ?C are 0/901 and 1/451 respectively. Palmetic, stearic and oleic acids constitute up to 82 % of its fatty acids and its main TAGs are POO (15/24 %), SOO (13/2%),OOO (8/67%), MOO (7/88%), POP (7/43%) and POS (6/56%). Fatty acids similarity of CHF and cocoa butter and presence of about 78 % oleic acid at sn-2 position of TAGs in CHF, make it a suitable choice to produce cocoa butter analog. Thus enzymatic interesterififcation of CHF and tristearin () with Lipozyme TL IM in supercritical carbon dioxide was done. Pressure, temperature, reaction time, Water percent and CHF to ratio, each one at three different levels, were as variables to determine optimum condition. Results from treatments at different levels of variables and analyzed with RSM indicate that CHF can be used in order to produce cocoa butter analog and every 5 variables are effective on amount of POS, POP and SOS, main TAGs of cocoa butter, and so on the yield of cocoa butter analog. 10 MPa, 42 ?C, 2/5 h reaction, 10 % water (weight of substrate) and 1:1/16 CHF to ratio are the best levels of variables.
