Preparation of Edible Corn Starch Phosphate with Highly Reactive Sodium Tripolyphosphate in the Absence of Catalyst

Purpose: To prepare edible corn starch phosphate under optimized experimental conditions.
Methods: Edible corn starch phosphate was prepared via the reaction of starch with active sodium tripolyphosphate. Reaction efficiency and viscosity were used as indices to optimize experimental conditions. Freeze-thaw stability and transparency of starch phosphate and native starch were comparatively studied.
Results: Starch phosphate with optimal combined phosphate content (0.39 %) was obtained under optimized conditions: reaction duration, 90 min; temperature, 160 oC; pH, 5.0; and phosphate, 1.5 g. Starch phosphate with optimal viscosity (230 cp) was obtained under different conditions: reaction duration, 120 min; temperature, 140 oC; pH, 6.0; and phosphate, 1.5 g. Significant differences (p < 0.05) were observed in syneresis and paste transparency of starch phosphate and native starch.
Conclusion: Edible corn starch phosphate has been successfully prepared under optimized experimental conditions whose freeze-thaw stability and paste transparency has obvious improvement compared with native starch.

Keywords
Starch phosphate; Combined phosphate; Sodium tripolyphosphate; Syneresis; Paste efficiency