Biological pigment of the tetrapyrroles is their connection in the biological oxidation process. Tetrapyrroles have a major role in electron transport and act as a replacement for many enzymes. They also have a role in the pigmentation of the marine organism's tissues. Melanin is a class of compounds that serves as a pigment with different structures responsible for dark, tan, yellowish / reddish pigments in marine animals. It is produced as the amino acid tyrosine is converted into melanin, which is found in the skin, hair, and eyes. Derived from aerobic oxidation of phenols, they are polymers. There are several different types
Skin-contact wine Skin-contact wine Skin-contact wine, skin-fermented wine, amber wine, or orange wine is a type of wine made from white wine grapes where the grape skins are not removed, as in typical white wine production, and stay in contact with the juice for days or even months. This contrasts with conventional white wine production, which involves crushing the grapes and quickly moving the juice off the skins into the fermentation vessel. The skins contain color pigment, phenols and tannins that would normally be considered undesirable for white wines, while for red wines skin contact and maceration is a vital part of