Starches See Also Chapters 17 and

Converted starches, also called thin-boiling starches, are produced by degradation of the starch chains into small segments. They can be cooked in water at higher concentrations than native starches. Low-viscosity starches are needed in applications where a high solid starch paste with a pumpable and workable viscosity is required. There are four classes of commercial converted starches dextrins (hydrolysis in solid-state) acid-modified starches (hydrolysis in a slurry) oxidized starches and enzymically depolymerized starches. 

Acid-modified starches are made by heating and stirring concentrated starch slurry with an acid at a temperature which is below the gelatinization temperature. When the desired viscosity or degree of conversion is reached, the acid is neutralized. Acid-modified starches are used in the food industry (candy). 

Enzymes such as a-amylase and (3-amylase can break the starch chains into maltodextrins and starch sugars such as glucose and maltose. The heat-stable enzymes convert the starch after dissolving the starch by jet-cooking. Enzymatically converted starches are used in the food industry (confectionery, baking products, sweeteners), paper industry (surface sizing) and the fermentation industry. 

When a starch is treated with bi- or multi-functional reagents, crosslinking occurs. The reaction takes place in a slurry. With increasing degrees of crosslinking, starch 

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