Extraktstoffen

Extraktstoffe are substances that can be dissolved and removed from a solid matrix by a suitable solvent. They are not chemically bound within the material, and their removal leaves behind a residue that is more tightly integrated with the matrix.

The concept is used across disciplines such as plant chemistry, wood science, and food technology. In plant material—leaves, bark, seeds, or essential oils—extractives encompass a broad range of compounds, including lipids, waxes, resins, tannins, phenolics, sugars, and volatile terpenes. Some extractives contribute fragrance, flavor, or biological activity even before chemical isolation.

In wood and timber, extractives are the portion that can be leached by organic solvents. They influence color, odor, decay resistance, and processing behavior, as well as interactions with adhesives and finishes. The specific profile of extractives varies with species, growth conditions, and drying history.

Extraction methods differ by target compounds and solvent choice. Common techniques include solvent extraction (maceration or Soxhlet), percolation, and modern approaches such as supercritical CO2 extraction. The solvent and conditions determine which substances are recovered.

Typical extractives include lipids and fatty acids, resins and terpenes, tannins, phenolic compounds, and various sugars and volatile constituents. Essential oils are a well-known subset obtained by distillation or solvent extraction and may be included under the broad term extractives depending on the context.

Applications and relevance vary: in flavor and fragrance chemistry, pharmacognosy, wood processing, and material science, knowing the extractive content helps explain odor, color, stability, and processing behavior. Analytical methods such as GC-MS and HPLC are commonly used to characterize extractives and quantify their amounts.

In summary, Extraktstoffe describe diverse, extractable substances that can be removed from a material by solvent extraction, with implications for aroma, color, stability, and processing.