Decoctions and long-simmer preparations

A decoction is a sustained simmer of hard material — root, bark, rhizome, woody stem, seed — where the cell walls are lignified and a short steep does not liberate much. The same chemistry as an infusion, run longer and hotter because the physical barrier is greater.

The tradeoff is real. Everything that increases extraction of the wanted compounds increases extraction of the unwanted ones too, and extends the time during which heat-labile compounds degrade. Roots and barks whose active fraction is a volatile monoterpene — ginger is the awkward example, being a rhizome whose interesting compounds are partly volatile — lose some of that fraction to prolonged boiling. A decoction of ginger for nausea is not necessarily better than an infusion of the same weight, which is why the remedy pages give the form the trials used.

The practical rules:

• Cold start, then raise. Soaking the material in cold water for 30 minutes before
• Cover it. Longer simmering means more opportunity to lose volatiles.
• Simmer, do not hard-boil. Vigorous boiling increases water loss and does not
• Strain while hot and press the marc gently. A lot of the active stays in the
• Reducing a decoction concentrates everything — including anything you would rather