Effects of pH, amino acids, hydrolyzed protein and potassium phosphate on caramelization were investigated for improvement of its reaction rate. The caramelization was performed with starch syrup at 110℃ and the different color functions-metric saturation(Suv), 5-hydroxymethylfurfural (HMF) contents and absorbance at 420 ㎚ were measured. As the pH was raised from 4 to 10, the reaction rate (Suv/hr) was increased by 31.9% along with significant increase in HMF content and absorbances at 420 ㎚. Among the several amino acids, arginine and glycine were very effective for improvement of caramelization, which may be due to Maillard reaction. When K₂HPO₄ were added in different ratio with arginine, glycine, HVP or HAP, the effects of arginine and HAP on the rate were markedly enhanced while the effects of glycine and HVP were rather reduced.