pomace

Pomace is the solid residue remaining after the extraction of juice, wine, or oil from fruit or olives. It typically consists of skins, pulp, seeds, and sometimes stems. The term is most commonly used for grape pomace, apple pomace, and olive pomace.

Grape pomace, or marc, is produced after pressing grapes for wine or juice. It includes grape skins, seeds, and residual pulp. Grape pomace can be distilled into pomace brandies such as grappa or marc, processed for polyphenol and tannin extraction, dried for animal feed, or used as a source of fiber and for composting.

Apple pomace is generated when apples are pressed for juice or cider. It is rich in dietary fiber and pectin, making it valuable for pectin production, as well as for animal feed, composting, or anaerobic digestion to produce biogas.

Olive pomace arises from olive oil production and consists of the solid remains after oil extraction, including skins, pulp, and seeds. After solvent extraction, the remaining material may be used to recover residual oil, and olive pomace can be processed into fuel, compost, or animal feed, depending on treatment. In some cases, olive pomace oil is produced from the residuals.

Environmental and economic considerations include the fact that pomace is a by-product with varying disposal costs. Valorization through extraction of bioactive compounds, production of industrial fibers, animal feed, compost, or bioenergy can improve efficiency and reduce waste in agricultural processing.