Optimization of starch sulfation process with a deep eutectic solvent-mixture of sulfamic acid:urea

Abstract

Abstract The process of sulphation of potato starch with a deep eutectic solvent, a mixture of sulfamic acid: urea, was optimized. The influence of varying factors was established - the ratio of sulfamic acid: urea (SAA: U), the ratio of starch: sulfating complex (St: SC) and the duration of the process on the sulfur content (wt.%) in the obtained starch sulfate. The data of analysis of variance for the obtained mathematical models indicate good prognostic properties. The optimal conditions for starch sulfation, which provide water-soluble sulfated starch with a high (up to 11.2% wt.) sulfur content, have been established. The optimal conditions for the process of sulfation of potato starch are the ratio SAA: U 1: 2.0-1: 2.2, the ratio St: SC 1: 3.5-1: 4.0 and the duration of the process is 118-120 minutes.