Thickener is a kind of food additive, which is mainly used to improve and increase the viscosity of food, maintain the color, fragrance, taste and stability of fluid food and jelly food, improve the physical properties of food, and make food feel smooth and delicious. Thickeners can improve the viscosity of food or form gel, thus changing the physical properties of food, making food sticky and suitable for taste, and have the functions of emulsification, stability or suspension. At present, there are 39 kinds of thickeners approved for use in China. Thickener is a hydrophilic polymer compound, also known as hydrosol. According to their sources, they can be divided into natural synthesis and chemical synthesis (including semi-synthesis). Basic chemical composition For most thickeners, their basic chemical composition is monosaccharide and its derivatives. Common monosaccharides include glucose, glucuronic acid, mannuronic acid, rhamnose, pyranose, guluronic acid and galacturonic acid.

For example, hydroxypropyl distarch phosphate is a starch derivative; The main ingredient of gelatin is protein; Pectin is a dietary fiber. Food thickeners are macromolecular substances, most of which are not digested and absorbed by human body. Such as gum, guar gum, carrageenan, etc. Their function is similar to that of dietary fiber. A few thickeners, such as gelatin, can be digested by human body, but the main component of gelatin is protein, which will be decomposed into amino acids after digestion and then participate in human metabolism, so it is a nutrient that can be absorbed and utilized. Thickeners include the following categories: inorganic thickeners (fumed silica, sodium bentonite, organobentonite, diatomite, attapulgite, molecular sieve and silica gel). Cellulose ether (methyl cellulose, hydroxypropyl methyl cellulose, sodium carboxymethyl cellulose, hydroxyethyl cellulose). Natural polymers and their derivatives (starch, gelatin, sodium alginate, casein, guar gum, chitosan, Arabic gum, xanthan gum, soy protein gum, natural rubber, lanolin, agar). Synthetic polymers (polyacrylamide, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene oxide, modified paraffin resin, carbomer resin, polyacrylic acid, polyacrylate emulsion, butadiene rubber, styrene-butadiene rubber, polyurethane, modified polyurea, low molecular weight polyethylene wax). Composite organometallic compound (amino alcohol composite titanate). Printing thickener includes (dispersed thickener, coating thickener and active thickener).