Progress in starch modification in the last decade

Starch is, after cellulose, the most abundant organic compound in nature. Modification of starch is carried out to enhance the positive attributes and to eliminate the shortcomings of the native starches. Various methods have been developed to produce a range of modified starches with a variety of characteristics and applications. Physically modified starches are simple and inexpensive because they can be produced without chemicals or even biological agents. In contrast, chemical modification is possible due to ubiquitous hydroxyl groups in starches that have been exploited for over a century, principally in the preparation of starch esters and ethers, but also in more subtle alterations, e.g., in order to tune the structure of starches for specific applications. All these techniques tend to alter the highly flexible starch polymer with changed physicochemical properties and modified structural attributes of high technological value for the food and non-food industries. Modification of starch is an ever evolving industry with numerous possibilities to generate novel starches which includes new functional and value added properties as demanded by the industry. This review aims to summarize the latest developments and recent knowledge regarding physically and chemically modified starches. This paper covers physical modification methods (pre-gelatinization, hydrothermal, and non-thermal processes), some chemical modifications and a combination of both.

Recent trend in the physical and chemical modification of starches from different botanical sources: A review

The development of green material in the last decade has been increased, which tends to reduce the impact of humans on the environment. Starch as an agro-sourced polymer has become very popular rec...

Physical and chemical modification of starches: A review

Preparation and physical characteristics of slowly digesting modified food starches

Designing hydrogel particles for controlled or targeted release of lipophilic bioactive agents in the gastrointestinal tract

Waxy maize (native and hydroxypropylated [HP]) and potato starches were impregnated with ionic gums (sodium alginate, CMC, and xanthan, 1% based on starch solids) and heat-treated in a dry state for 0, 2, or 4 hr at 130°C. Effects of the dry heating on paste viscosity (RVA) and clarity (light transmittance) were examined. Heat treatment with sodium alginate and CMC raised the paste viscosities of native and HP waxy maize starches, but decreased that of potato starch. Xanthan provided the most substantial changes in paste viscosity among the tested gums. It appeared to heavily restrict granule swelling of the waxy maize starches, but it increased swelling of potato starch granules. Dry heating raised the paste viscosity of all the starch-gum mixtures tested, except the potato starchalginate mixture. The final viscosity at 50°C of a 7% paste was raised in all other starches by ≈500–1,000 cP by this treatment. The paste of waxy maize starch-gum products became opaque and shorter textured by the heat...

Modification of Starch by Dry Heating with Ionic Gums

Waxy maize and potato starches were dispersed in pH 6.0 and 8.0 aqueous solutions (1%) of an ionic gum (sodium alginate, sodium carboxymethylcellulose, and xanthan). The mixture was dried at 45°C overnight and then heat-treated 2 hr at 130°C. Effects on the paste viscosity of the products in a pH 7.0 buffer were examined. Heating with sodium alginate or sodium carboxymethylcellulose (CMC) increased the paste viscosity of waxy maize starch but reduced that of potato starch. In both starches, xanthan effected greater viscogram changes than did sodium alginate or CMC. Use of xanthan in the treatment produced products with restricted granular swelling and increased shear stability of the pastes. The pH of the starch-gum mixtures affected the thermally induced viscosity changes. Mild acidity (pH 6.0) effected a viscosity decrease for the heat-treated starch product, whereas alkalinity (pH 8.0) raised the viscosity regardless of the presence of gum. But pH 6 before heat treatment was favored for viscos...

H. S. Lim

Papers

Modification of Starch by Dry Heating with Ionic Gums

Effect of Dry Heating with Ionic Gums at Controlled pH on Starch Paste Viscosity