| Abstract: | Phosphate diesters of waxy maize starch were prepared by crossbonding reactions using various concentrations of phosphorus oxychloride (POCl3) under conditions of controlled pH and temperature in order to have the modified starch with better functional properties. The waxy maize starch treated with 350 ppm POCl3 (D. B.) showed higher paste viscosity and better heat resistance and acid proofing at a range of pH 3.0–4.0 than the unmodified starch and the other diesters prepared using 250–1,000 ppm POCl3. The viscosity at 25°C of 4% pastes, added salt, sugar and acid simulating a kind of brown sauce and cooked at 95°C for 10 min, containing the diester prepared by either 350 or 1,000 ppm POCl3, was higher and more stable in a refrigerator up to 4 months than that of the unmodified waxy maize starch. Application of the diester (1,000 ppm POCl3) to an effective thickener for “instant Miso soup” was also investigated. |
