Denaturation purpose
First, to meet the requirements of various industrial applications. For example, high-temperature technology (canning sterilization) requires good high-temperature viscosity stability of starch, frozen food requires good freeze-thaw stability of starch, and jelly food requires good transparency and film formation. The second is to open up new uses of starch and expand the scope of application. For example, starch is used in textiles; Hydroxyethyl starch and hydroxypropyl starch replace plasma; High cross-linked starch replaces talc powder used in surgical gloves.
Denaturation mode
1. Physical denaturation
Pregelatinization( α- Starch γ Radiation treated starch, ultra-high frequency radiation treated starch, mechanical grinding treated starch, wet heat treated starch, pre gelatinized starch, oil modified starch, smoked modified starch, extruded modified starch, metal ion modified starch, ultra-high pressure radiation modified starch, etc.
2. Chemical denaturation
Modified starch obtained by treating with various chemical reagents. There are two categories: one is to reduce the molecular weight of starch, such as acid hydrolyzed starch, oxidized starch, baking dextrin, etc; The other is to increase the molecular weight of starch, such as cross-linked starch, esterified starch, etherified starch, grafted starch, etc.
3. Enzymatic denaturation
(Biological modification): starch treated with various enzymes. as α、β、γ- Cyclodextrin, maltodextrin, amylose, etc.
4. Compound denaturation
Modified starch obtained by more than two treatment methods. Such as oxidized cross-linked starch, cross-linked esterified starch, etc. The modified starch obtained by compound modification has the respective advantages of the two kinds of modified starch.
In addition, modified starch can also be classified according to the production process route, including dry method (such as phosphate starch, acid hydrolyzed starch, cationic starch, carboxymethyl starch, etc.), wet method, organic solvent method (such as alcohol as the solvent for the preparation of carboxyl starch), extrusion method and roller drying method (such as natural starch or modified starch as the raw material to produce pre gelatinized starch), etc