Modified starch

Modified starch Some starches have been altered to yield a wide variety of modified starches, extending their usefulness in food processing.

It has been chemically or physically modify to create unique functional characteristics which contribute to shelf stability, appearance, convenience and performance in food preparation.

One or more modification process are used: mild oxidation or bleaching, moderate oxidation, acid or enzyme depolymerization, monofunctional esterification, polyfunctional esterification, mono-functional etherification, alkaline gelatinization and certain combination of these treatments.

Many commercial derivatives are produced by the addition of reactive, organic reagents to aqueous starch slurries while controlling alkalinity (pH 7-9 for esterification and pH 11-12 for etherification ) and temperature (typically less than 60 ° C).

The modifications may affect the starch’s gelatinization, heating times, freezing stability, cold water solubility or viscosity.

There are many types of modified starch. Each one has a different function depending on the way the starch has been modified. Three types of modified starch are: 
Cross linked starch
Oxidized starch
Instant to pre-gelatinized starch

Cross linked starch is to enable the starch to withstand such conditions as low pH, high shear or high temperature.

While pre –gelatinized starch can dispersible in cold water and can thicken without heat being applied. It also can be cooked and dried, yet is able to reabsorb a lot of water in preparation without cooking the food.

Modified food starches are insoluble in alcohol, in ether and in chloroform.
Modified starch