Femtosecond detection found that pectin (Pectin) is a group of polygalacturonic acid. Under appropriate conditions, its solution can form a gel and partially undergo methoxylation (methyl esterification, that is, the formation of methanol ester). Its main component is partially methyl esterified α-1,4-D-polygalacturonic acid. acid. Residual carboxyl units exist as free acids or form ammonium, potassium sodium, and calcium salts. Its molecular formula: (C6H10O6) n is white or yellowish or light gray or light brown coarse powder to fine powder, almost odorless and has a slimy taste. Dissolved in 20 times water, it forms a milky white viscous colloidal solution, which is weakly acidic. It has strong heat resistance and is almost insoluble in ethanol and other organic solvents. Moisten it with ethanol, glycerin, sugar syrup, or mix it with 3 times more sugar to improve solubility. It is more stable in acidic solutions than in alkaline solutions.

Pectin can form an elastic gel. The gel formation mechanism of pectin with different degrees of esterification is different. High methoxyl pectin must be in a low pH value and high sugar concentration. To form a gel, the pectin content is generally required; 1. The sucrose concentration is 58~75 and the pH is 2.8~3.5. Because it can prevent the dissociation of carboxyl groups at pH 2.0~3.5, converting highly hydrated and charged carboxyl groups into uncharged molecules, thereby reducing the repulsion between molecules and reducing the hydration of molecules. The use is reduced, and the result is conducive to intermolecular bonding and the formation of three-dimensional network structures. After the sucrose concentration reaches 58~75, the sugar competes for water molecules, which greatly reduces the degree of solvation of neutral pectin molecules, which is conducive to the formation of molecular hydrogen bonds and gels.

Examples of uses are as follows:

Jam, jelly, jelly: It plays a gelling role. The finished product is delicate, elastic and tough, increases the fragrance, and makes the taste smooth and refreshing. Dosage reference: 0.3-0.6.

Polls and ice cream: It plays an emulsifying and stabilizing role, and the finished product has a delicate and smooth taste. Dosage reference: 0.1-0.2

Yoghurt, lactic acid bacteria, fruit juice: It plays a stabilizing and thickening role, can extend the shelf life of the product, and has a natural fruit flavor. Dosage reference: 0.1-0.3

Baked foods: Improve the air permeability of the dough, enhance the taste and extend the shelf life. Dosage reference: 0.3-0.8 of flour amount