**2. Uses of plant extracts in food industry**

Plants have also been used in the production of stimulant beverages, such as tea, coffee, cocoa, and cola, and intoxicants, such as wine, beer, and kava, in many cultures since ancient times. Tea (*Camellia sinensis* Kuntze) was first consumed in ancient China [1], while coffee (*Coffea arabica* L.) was initially found in Ethiopia from the region called Keffa and then cultivated in Yemen for commercial purposes in the ninth century [32]. The Aztec nobility is used to consume bitter beverages containing raw cocoa beans (*Theobroma cacao* L.), red peppers, and various herbs [32]. The active components of these stimulants are methylated xanthine derivatives, called caffeine, theophylline, and theobromine, major components of coffee, tea, and cocoa, respectively [8].

Studies have shown that a low to moderate consumption of red wine is important for reduction of mortality caused by cardiovascular disease and cancer [33]. This health benefit of wine has been suggested to be due to the presence of a compound called resveratrol present in the skin of grapes [34].

Kava, a beverage made from the root of *Piper methysticum* Roxb., has been a popular intoxicating beverage in Polynesia for centuries [35]. However, in the Western world, kava is not normally consumed directly but has gained popularity as a botanical dietary supplement to ease the symptoms of stress, anxiety, and depression [36]. A study has shown that the anxiolytic activity of kava extract may be mediated in part by the kavalactone and dihydrokavain [37].
