Hydroxypropylated starch cross-linked

Starch source DS (Acetylated) MS (Hydroxypropylated) DS (Cross-linked)... 

Hung, P. V, Morita, N. (2005). Physicochemical properties of hydroxypropylated and cross-linked starches from A-type and B-type wheat starch granules-Review. Carbohydr. Polym., 59,239-246. 

In industrial production of acid-modified starches, a 40% slurry of normal com starch or waxy maize starch is acidified with hydrochloric or sulfuric acid at 25—55°C. Reaction time is controlled by measuring loss of viscosity and may vary from 6 to 24 hs. For product reproducibiUty, it is necessary to strictly control the type of starch, its concentration, the type of acid and its concentration, the temperature, and time of reaction. Viscosity is plotted versus time, and when the desired amount of thinning is attained the mixture is neutralized with soda ash or dilute sodium hydroxide. The acid-modified starch is then filtered and dried. If the starch is washed with a nonaqueous solvent (89), gelling time is reduced, but such drying is seldom used. Acid treatment may be used in conjunction with preparation of starch ethers (90), cationic starches, or cross-linked starches. Acid treatment of 34 different rice starches has been reported (91), as well as acidic hydrolysis of wheat and com starches followed by hydroxypropylation for the purpose of preparing thin-hoiling and nongelling adhesives (92). 

Wattanchant, S., Muhammad, K., Hashim, D., Rahman, R. A. (2003). Effect of cross-linking reagents and hydroxypropylation levels on dual-modified sago starch properties. Food Chem., 80, 463 71. 

Woo, K. S., Seib, P. A. (1997). Cross-linking of wheat starch and hydroxypropylated wheat starch in alkaline slurry with sodium trimetaphosphate. Carbohydr. Polym., 33, 263-271. 

Yeh, A. L, Yeh, S. L. (1993). Property differences between cross-linked and hydroxypropylated rice starches. Cereal Chem., 70, 596. 

Zheng, G. H., Han, H. L., Bhatty, R. S. (1999). Functional properties of cross-linked and hydroxypropylation waxy hull-less barley starches. Cereal Chem., 76,182-188. 

Starches have been chemically modified to improve their solution and gelling characteristics for food applications. Common modifications involve the cross linking of the starch chains, formation of esters and ethers, and partial depolymerization. Chemical modifications that have been approved in the United States for food use, involve esterification with acetic anhydride, succinic anhydride, mixed acid anhydrides of acetic and adipic acids, and 1-octenylsuccinic anhydride to give low degrees of substitution (d.s.), such as 0.09 [31]. Phosphate starch esters have been prepared by reaction with phosphorus oxychloride, sodium trimetaphosphate, and sodium tripolyphosphate the maximum phosphate d.s. permitted in the US is 0.002. Starch ethers, approved for food use, have been prepared by reaction with propylene oxide to give hydroxypropyl derivatives [31]. 

The reaction of a cross-linked starch with sodium 2-chloroethyl-3-chloro-propyl- or 3-chloro-2-hydroxypropyl-sulphonate has been used in the preparation of ion-exchange matrices. The reaction with 3-chloro-2-hydroxypropyl-sulphonate proceeded in high yield, even at low temperatures, and did not require an organic solvent. 

These include cross linked or inhibited starches, hydroxypropylated starches, phosphorylated starches, starch succinates, grafted starches, and carboxymethyl starch. ... 

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