Never add glycerine to hot liquids as it is temperature sensitive and will coagulate. Always mix with cold or warm liquids. Fluid extracts are used both to concentrate and preserve the active ingredients of an herb. Fluid extracts are considered by many herbalists to be the preferred way to preserve water soluble active ingredients. When properly made one fluid ounce of fluid extract equals one ounce of fresh herb.
Alcohol is ideal for extracting fats, resins, waxes and most alkaloids.
It is an excellent preservative and is quickly assimilated. The substance used to extract the herbs is known as the menstrum. The herbs you are tincturing are known as the mark. Prepare the herbs by chopping or grinding them. Tincture several herbs together if you are creating a formula.