Abstract:

The semi-dry preparation of starch phosphate monoesters from corn starch was optimized using orthogonal array design. The optimal reaction system was found to consist of 9% sodium polyphosphate and 2% urea at pH 5.0 and the reaction was allowed to proceed for 2 h at 150 ℃, and the degree of substitute was up to 0.0516 under these conditions. The established process was stable and repeatable. A higher degree of substitute was obtained at a higher reaction temperature of 180 ℃, but the color of the obtained product needed to be improved. Starch containing 15% moisture was beneficial for the reaction, producing better product color.

Key words: starch phosphate monoesters, preparation process, semi-dry process