Olijfpomace

Olijfpomace is the solid byproduct left after extracting olive oil from olives. It is primarily composed of skins, pulp, and seeds, and contains some residual oil, depending on the extraction method. The material is generated in substantial quantities by olive mills, especially those using two-phase or three-phase systems. Its moisture content is typically high, and the precise composition varies with olive cultivar, processing method, and season.

Two-phase mills produce a wetter pomace paste, while three-phase mills yield a drier solid. Residual oil in olijfpomace generally accounts for a small percentage of the dry weight but can be significant enough to recover in some operations. The matrix also contains fiber, polyphenols, fatty compounds, and minerals. Because of these constituents, olijfpomace can present odor and environmental management challenges if not treated or stored properly.

Uses include energy production, soil amendment, and recovery of bioactive compounds. Dried olijfpomace can be burnt as a biomass fuel, or pelletized for use in heat and power generation. It may also be processed in anaerobic digestion to produce biogas. Composting or conversion into soil conditioner is possible, though high polyphenol content and fats may slow decomposition and require mixing with other organic materials or pretreatment. Some value-added products extract polyphenols for cosmetics or nutraceuticals.

Environmental and regulatory aspects: as a byproduct, olijfpomace is managed under waste regulations in many regions and may require pretreatment before land application or disposal. Improper storage can cause odors and leachate; appropriate drying, covering, and containment are common practices. In some cases, processors separate the olive mill wastewater (OMW) alongside the pomace for environmental compliance.