According to the chemical structure and composition of thickeners, they can be divided into polysaccharide and polypeptide. Polysaccharide thickeners include starch, cellulose, pectin, alginic acid and so on, which are widely distributed in nature. The main thickeners are gelatin, sodium caseinate and cheese crisp.

According to the ionic properties of thickeners, they can also be divided into two categories: ionic thickeners, such as alginic acid, sodium carboxymethyl cellulose and starch; non-ionic thickeners, such as propylene glycol sodium alginate and hydroxypropyl starch.

According to the source of thickener, it can be divided into natural thickener and synthetic thickener. Among them, natural thickeners can be further divided into animal thickeners (gelatin, sodium caseinate, etc.), plant thickeners (guar gum, Arabic gum, pectin, agar, carrageenan, etc.), microbial thickeners (xanthan gum, gellan gum, etc.) and enzyme treated thickeners (enzyme hydrolyzed guar gum, enzyme treated starch, etc.). The main synthetic thickeners are modified starch, modified cellulose, propylene glycol alginate and xanthan gum.

According to the relative molecular weight of thickeners, there are low molecular weight thickeners and high molecular weight thickeners. Among them, low molecular weight thickeners and high molecular weight thickeners can be further classified according to the functional groups contained in their molecules, mainly including inorganic thickeners, cellulose, fatty alcohols, fatty acids, ethers, polyacrylates and associated polyurethane thickeners.