Herbal Tea Profile
By industry terms, the use of “tea” to describe anything that does not originate from the Camellia sinensis plant is incorrect. To stay in tune with the American vernacular of English, however, the use of "herbal tea" to describe herbal infusions seems efficient and appropriate.
Herbal tea is properly termed as “herbal infusion” or “tisane” in industry vocabulary. It refers to anything that is infused in hot water and not from the Camellia sinensis plant, a bean plant (i.e. coffee), or anything containing caffeine.
The roots of tisanes, like tea, are often medicinal; in many cases tisanes were the first form of medicine for peoples across the world. Tisanes are often composed of flowers, leaves, bark, roots, etc., whereby the infusion of the herbal product into hot water allows for the extraction of organic chemical and medicinal compounds into a form more palatable and active for human consumption (please note some herbal infusions can be toxic). Tisanes are categorically limited to caffeine-free compounds; maté and guarana are of plant origin also but are independently categorized for containing xanthines, energizing caffeine-like compounds.
Listed below are a few common herbal components used in tea:
Flowers: Flowers are not only a visually attractive component of teas, but contain many essential oils. These oils often contain many medicinal compounds of interest. A common 100% flower tea, for example, is chamomile, which is revered as a digestive aid.
Roots: Infused roots tend to be bitter in flavor because of the alkaline compounds found in the roots. These bitter compounds are often medicinally beneficial; however, in high quantities they can be quite toxic. A popular root used in many tea products is ginseng.
Bark: Cinnamon is a popular herbal bark infusion used in tea. Pieces of the bark are peeled off and then usually ground.
Bush tea refers to herbal tea made from the ground up: branches, rather than the leaves, of a plant. This, for example, is how rooibos and honeybush are produced.
Brewing
Herbal infusions tend to brew best at a water temperature close to boiling. Seeds and nuts usually require longer steeping times than flowers or leaves.
Trending Research
Because the category of herbal infusions encompasses so many different types of plants, there is a wide variety of research for the various medicinal uses of these herbals. Throughout human history, people of various cultures and geographic regions have used herbal infusions medicinally. Since 1999 the WHO has created an ongoing series exploring to explore the “safety, efficacy, and quality control of widely used medicinal plants”
Another resource I often consult isUniversity of Michigan-Dearborn Native American Ethnobotany Database. It is one of the best resources for native medicinal herbs used in the Mid-Western United States.