waterextractables

Waterextractables, or water-extractables, are substances present in a material that dissolve in water under defined conditions. They are typically quantified by extracting a sample with water for a prescribed time and temperature and measuring the dissolved material, usually as a percentage of dry weight.

In wood science and wood products, water-extractives refer to non-structural components soluble in water, such as simple sugars, organic acids, phenolics, tannins, resins, fats, waxes, and inorganic salts. The amount and composition of water-extractives influence properties like color, odor, workability, decay resistance, and dimensional stability, and they can affect processing and finish quality.

Extraction procedures vary by standard but often involve rinsing or soaking under agitation, followed by filtration and drying to determine the extractives mass. The term is used in quality control, species identification, and in evaluating processing effects (for example, thermal treatment) on extractives.

Outside wood science, water-extractables are discussed in the context of food packaging, textiles, and polymer materials, where soluble leachables can migrate into products and affect safety, stability, or aesthetics. They are also relevant to soil and environmental science when assessing soluble components leached from soils or anthropogenic materials.

Limitations include that water extraction captures only water-soluble compounds under the tested conditions; some compounds may require aqueous solutions of different pH or organic solvents to extract, and the results depend on temperature, duration, and agitation.