Collagen is extracted from animal skin or bone, it is a kind of protein, belongs to the human body one of the 6 major nutrients, itself is hormone-free.
Collagen is a biological macromolecule, the main component of animal connective tissue, but also the most abundant and widely distributed functional protein in mammals, accounting for 25% to 30% of the total amount of protein, and some organisms even up to 80% or more. Animal tissues of animal and poultry origin are the main way for people to obtain natural collagen and its collagen peptides.
The collagen content in aquatic animals is higher than that in terrestrial animals, such as silver carp, bighead carp and grass carp skin protein content of 25.9%, 23.6% and 29.8%, respectively, which are higher than their respective corresponding protein content of fish meat: 17.8%, 15.3% and 16.6%. The collagen content in the skin of the fish can be up to more than 80% of its total protein, much higher than other parts of the fish body.
One study reported that the collagen in the skin of real seabream accounted for 80.5 percent of the crude protein, while that of eel was as high as 87.3 percent. Such a high content means a high yield, such as small tuna bonito 42.5%; Japanese sea bass 40.7%; aromatic fish 53.6%; yellow sea bream 40.1%; and mackerel 43.5% (all on a dry weight basis).
Expanded Information
Collagen is generally a white, transparent powder with elongated rod-shaped molecules and a relative molecular mass ranging from about 2kD to 300kD. Collagen has a strong extension force, insoluble in cold water, dilute acid, dilute alkali solution, with good water retention and emulsification.
Collagen is not easily hydrolyzed by general protease, but can be broken by animal collagenase, broken fragments of automatic denaturation, can be hydrolyzed by ordinary protease. When the environmental pH is lower than neutral, the denaturation temperature of collagen is 40~41℃, and when the environmental pH is acidic, the denaturation temperature of collagen is 38~39℃.
Baidu Encyclopedia - Collagen