Carrageenan (Carrageenan) originally originated in Carraghan County, southern Ireland. /kloc-industrial production began in the 0/8th century. At present, the main raw materials are red algae such as Eucheuma, Keratophyllum and Taxodium. According to the different sulfate groups on galactose residues, it can be divided into κ-type, ι-type and λ-type. In chemical structure, sulfated or non-sulfated galactose and 3,6-dehydrated galactose are alternately connected by α- 1 3 glycosidic bond and β- 1 4 bond, and the D galactose unit C4 connected by 1 3 has 1 sulfate groups. The molecular weight is above 200,000.
Its chemical characteristics are mainly:
Solubility: it can be dissolved in cold water, and the dissolution rate is increased in hot water above 70℃;
● Gelatinity: It can generate thermoreversible gel in the presence of potassium ions;
Thickening: when the concentration is low, a low-viscosity sol is formed, which is close to Newtonian fluid; when the concentration is high, a high-viscosity sol is formed, which is a non-Newtonian fluid.
● Synergy: Synergy with locust bean gum, konjac gum, xanthan gum and other colloids can improve the elasticity and water retention of the gel;
● Health value: Carrageenan has the basic characteristics of soluble dietary fiber. Carrageenan degraded in vivo can form a soluble complex with fibrin. It can be decomposed into CO2, H2, biogas, formic acid, acetic acid, propionic acid and other short-chain fatty acids by coliform bacteria, and become the energy source of probiotics.
Therefore, it is mainly used for:
● Jelly, pudding ● Soft candy
● Meat products ● Cold drinks
● Dairy products ● Liquor clarifier
● Drinks ● Pet food
When it comes to Agar, agar is a kind of seaweed polysaccharide mainly extracted from red algae such as agar, Gracilaria, laver at the end of the period, and chickpea with hot water. It is the earliest gelling agent used by human beings.
Chemical structure of agar
The chemical structure of agar is complex, and it is generally considered to be a chain-type molecular neutral sugar composed of agarobiose as the skeleton. The agarobiose is a chain-type molecular neutral sugar with β-D- galactopyranose linked by 1 3 and 3,6-inner ether -α-L- galactopyranose linked by 1 4. In addition, it also contains a small amount of L- galactose, 6- methyl -D- galactose and D- xylose, as well as sulfate, pyruvate and glucuronic acid.
Colloidal chemical characteristics of agar
● Solubility: insoluble in cold water and inorganic and organic solvents. It can be dissolved in water when heated above 85℃;
Gelatinity: after being heated and dissolved in water, it is cooled to 28-35℃ to form gel.
● Gel strength: the greater the degree of molecular polymerization and the longer the molecular chain, the greater the gel strength; The content of galactose also affects it;
● Synergism with locust bean gum, konjac gum and xanthan gum can improve the elasticity and water retention of the gel.