ANSWER

Despite the supposed universality of bitter taste, many commonly consumed beverages such as fruits, tea, coffee and chocolate also have bitterness as a major sensory attribute. There are a few ingredients that could contribute to the bitter taste in beverages.

a. Tannins

Tannins, also known as Tannic Acid, exist in a group of pale-yellow to light brown amorphous substances in the form of powder, flakes or a spongy mass. Tannins are astringent, bitter plant polyphenols that either bind and precipitate or shrink proteins. They add bitterness and astringency as well as complexity into beverages. Soluble, astringent materials are found in some plants like tea and is highly soluble in water (Praveen et al., 2012).

 b. Nopal (Prickly pear cactus)

Nopal (Opuntia streptacantha Le-maire) is also known as a prickly pear and are members of the Cactacceae or cactus family. The bitter components in Nopal include Isorhamnetin-glucoside, kaempferol (known bitter-tasting flavonoid glycoside) luteolin and rutin. They are heat-resistant antioxidants (WIPO Patent WO 2011026606 A2, 2010).

References

Luisa, R., Salvatore, M. & Alberto, S. (2010). Compositions for the treatment of hemorrhoids and related disease. WIPO Patent WO 2011026606 A2.

Praveen, K. A. & Kumud, U. (2012). Tannins are Astringent. Journal of Pharmacognosy and Phytochemistry, 1(3), 45-50.