Camellia sinensis tea is considered to be the most consumed beverage in the world after water (Chan et al., 2010:185; Ziaedini et al., 2010:505; Moodley et al.
, 2015:7519), and it is one of the world’s oldest known prepared beverage originating in China (Manteiga, Park ; Ali, 1997). Tea has no caffeine, contains very low levels of tannins and has health-promoting properties (Mabizela, Slabbert ; Bester, 2017:75). Herbal tea and black tea are the two main categories available on the market (Moodley et al., 2015:7519). Herbal tea is any tea that is not produced from the Camellia sinensis plant (Moodley et al.
, 2015:719). Herbal remedies are often prepared in the form of tea, by mixing dried parts of a plant in boiling water (Chan et al., 2010: 185). Tea quality is mainly influenced by the bioactive compounds present in tea leaves (Ziaedini et al., 2010:505; Moodley et al.
, 2015:7519). Polyphenol compounds such as flavonoids and phenolic acids can be found in tea. The contents found in the raw material of polyphenol compounds can determine their antioxidant activity (Moodley et al.
, 2015:7519). As reported by Chan et al. (2010:185), herbal teas are popular for their fragrance, antioxidant properties, and therapeutic applications.Herbal tea has gained popularity in the United Kingdom, and now it accounts for 3-4% of tea consumed (Phelan ; Rees, 2003:241).
According to Craig (1999), the world is witnessing a large interest in the consumption of herbal remedies. In the United States, the annual sale of medicinal herbs and related commodities now exceeds $2 billion (Craig, 1999). Herbal food stores sell hundreds of different herbal teas (Chan et al., 2010: 185). As reported by McKay and Blumberg (2006:619), the use of herbal preparations, produced by steeping or heating crude plant material has succeeded for centuries. Europe and Asia healthcare providers prescribe herbal tea as an alternative to other beverages (McKay ; Blumberg, 2006:619) because herbs have shown to contain multiple ingredients (Bent, 2008:854).In South Africa, a number of plants have traditionally been used as herbal teas (Joubert et al.
, 2008:377). However, only a few South African herbal plants have enjoyed commercial success as herbal teas. Aspalathus linearis (rooibos) and various species of Cyclopia Vent (Honeybush) are some of the South African species that have been converted from wild harvest crops to a commercially viable agribusiness (Reinten and Coetzee, 2002:79; Tiedtke ; Marks, 2002; Joubert et al.
, 2008:377). In Europe, peppermint (Mentha piperita L.) is regarded as the most popular single ingredient herbal tea (McKay ; Blumberg, 2006:619). In China, Asthma was treated by using a Chinese herb known as ephedra (Ma huang), which contains active substance ephedrine (Craig, 1999).
Ephedra was used for thousands of years by traditional Chinese, whereas in America it only became popular in the1990s as a source for weight loss and energy enhancing product (Bent, 2008:857). The American Indians are reportedly using native herbs for food and medicinal purposes. Some of the herbs used by American Indians are bee balm, black cohosh, elderberry, ginseng, goldenseal, mayapple, partridgeberry, ragweed, snakeroot, and yarrow (Craig, 1999).
