The Preparation And Properties Research Of Partial-gelatinized Starch Slurry

Starch-based sizes have characteristics of extensive source, low cost, and goodbiodegradability. The partially-gelatinized starch slurry（PGSS）produced from starch, has lowviscosity, stable properties and good liquidity. This paper prepared the PGSS in differentways using corn starch as raw materials and established a process for producing slurry withrelatively stable viscosity. The structure changes of the granules in PGSS made from differentpreparing processes were revealed, which provides a theoretical basis that how we canproduce the PGSS with the stable viscosity properties. In addition, in order to improve theapplication performance of the PGSS, this paper also discusses the effect of the dosage ofmodified starch PR-Su on the viscosity stability of the PGSS.The results showed that the PGSS with low viscosity and good stability could beobtained at65℃using constant temperature (CT) method and64℃using steamheating(SH) method, respectively. The SH method at64℃is an ideal method for producingthe PGSS using starch as raw material because the obtained PGSS showed lower viscosity(5-7mPa.s), better viscosity stability and better liquidity at low temperature condition.Comparing these two preparation methods of PGSS properties, the study found that thePGSS produced at different temperatures present different polarization characteristics, and thecrystallinity of starch granules decreased, while the degree of gelatinization, particle size andswelling potential increase gradually. The gelatinization degrees of PGSS produced by the CTmethod at65℃and SH at64℃were65.63%and72.22%, respectively, which showed thestarch granules were not fully gelatinized. At the same time, the PGSS produced by the twomethods had moderate expansion potential and particle size, which caused lower viscosity,better viscosity stability, good liquidity and suspension stability. It showed extremelysignificant positive correlation and linear relationship between the viscosity of the PGSS andaverage particle size and swelling potential.The PGSS were, produced from raw starch mixed with PR-Su using CT and SH methodsand the result showed that the addition of PR-Su could further lower the viscosity of PGSS.When the ratio of PR-Su and the original starch in slurry was1:3or less, the viscositystability of the PGSS made by SH method was obviously higher than CT method. Therefore,the PGSS produced by SH method is more suitable for the actual production.