EVALUATION OF MICROENCAPSULATED TURMERIC OLEORESIN FOR PRE-EXTRUSION COLORING USING RESPONSE SURFACE METHODOLOGY

摘要

This work evaluates turmeric oleoresin (TO) vis-a-vis that microencap-sulated in two wall materials, viz- gum arablc (TO-GA) and n-octenyl succinic anhydride (n-OSA) starch (TO-MS), as pre-extrusion coloring of sorghum extrudate for maximum retention of color. The effect of the extrusion conditions on the retention of turmeric color during extrusion of sorghum flour -chosen as a model having parameters die temperature, screw speed and moisture content-was studied using response surface methodology. Experiments were carried out by extrusion of sorghum flour containing 1% oleoresin, and microencapsulated oleoresins using a single-screw extruder at a constant feed rate of 55 g/min. At all conditions of extrusion, both the microencapsulated oleoresins gave a better retention of color than the free oleoresin. Experiments using the optimized levels of the parameters showed a good agreement between the experimental and the predicted values of color.