Theaflavins (TFs) and Thearubigins (TRs) are two distinct groups of polyphenolic compounds found in black tea, each with unique chemical compositions and properties. Understanding the differences between these compounds is essential for comprehending their individual contributions to the characteristics and health benefits of black tea. This article aims to provide a comprehensive exploration of the disparities between Theaflavins and Thearubigins, supported by evidence from relevant research.
Theaflavins and thearubigins are both flavonoids that contribute to the color, flavor, and body of tea. Theaflavins are orange or red, and thearubigins are red-brown. Theaflavins are the first flavonoids to emerge during oxidation, while thearubigins emerge later. Theaflavins contribute to the tea's astringency, brightness, and briskness, while thearubigins contribute to its strength and mouth-feel.
Theaflavins are a class of polyphenolic compounds that contribute to the color, flavor, and health-promoting properties of black tea. They are formed through the oxidative dimerization of catechins during the fermentation process of tea leaves. Theaflavins are known for their antioxidant and anti-inflammatory effects, which have been linked to various health benefits, including cardiovascular protection, anti-cancer properties, and potential anti-aging effects.
On the other hand, Thearubigins are large polyphenolic compounds that are also derived from the oxidation of tea polyphenols during the fermentation of tea leaves. They are responsible for the rich red color and the characteristic flavor of black tea. Thearubigins have been associated with antioxidant, anti-inflammatory, and skin-protective properties, making them a subject of interest in the field of anti-aging and skincare.
Chemically, Theaflavins are distinct from Thearubigins in terms of their molecular structure and composition. Theaflavins are dimeric compounds, meaning the combination of two smaller units forms them, while Thearubigins are larger polymeric compounds resulting from the polymerization of various flavonoids during tea fermentation. This structural dissimilarity contributes to their different biological activities and potential health effects.
| Theaflavins | Thearubigins | |
| Color | Orange or red | Red-brown |
| Contribution to tea | Astringency, brightness, and briskness | Strength and mouth-feel |
| Chemical structure | Well-defined | Heterogeneous and unknown |
| Percentage of dry weight in black tea | 1–6% | 10–20% |
Theaflavins are the main group of compounds used to assess the quality of black tea. The ratio of theaflavins to thearubigins (TF:TR) should be 1:10 to 1:12 for high-quality black tea. Fermentation time is a major factor in maintaining the TF:TR ratio.
Theaflavins and thearubigins are characteristic products formed from catechins during the enzymatic oxidation of tea during manufacturing. Theaflavins give an orange or orange-red color to tea and contribute to a mouthfeel sensation and an extent of cream formation. They are dimeric compounds that possess a benzotropolone skeleton that is formed from the co-oxidation of selected pairs of catechins. The oxidation of the B ring of either (−)-epigallocatechin or (−)-epigallocatechin gallate is followed by loss of CO2 and simultaneous fusion with the B ring of (−)-epicatechin or (−)-epicatechin gallate molecule (Figure 12.2). Four major theaflavins have been identified in black tea: theaflavin, theaflavin-3-monogallate, theaflavin-3′-monogallate, and theaflavin-3,3′-digallate. Additionally, their stereoisomers and derivatives can be present. Recently, the presence of theaflavin trigallate and tetragallate in black tea was reported (Chen et al., 2012). The theaflavins can be further oxidized. They are probably also the precursors for the formation of polymeric thearubigins. However, the mechanism of reaction is not known hitherto. Thearubigins are red-brown or dark-brown pigments in black tea, their content accounts for up to 60% of the dry weight of tea infusion.
In terms of health benefits, Theaflavins have been extensively studied for their potential role in promoting cardiovascular health. Research has suggested that Theaflavins may help reduce cholesterol levels, improve blood vessel function, and exert anti-inflammatory effects, all of which are beneficial for cardiovascular health. Additionally, Theaflavins have shown the potential to inhibit the growth of cancer cells and may have anti-diabetic properties.
On the other hand, Thearubigins have been associated with antioxidant and anti-inflammatory effects, which are crucial for combating oxidative stress and inflammation in the body. These properties may contribute to the potential anti-aging and skin-protective effects of Thearubigins, making them a subject of interest in skincare and age-related research.
In conclusion, Theaflavins and Thearubigins are distinct polyphenolic compounds found in black tea, each with unique chemical compositions and potential health benefits. While Theaflavins have been linked to cardiovascular health, anti-cancer properties, and potential anti-diabetic effects, Thearubigins have been associated with antioxidant, anti-inflammatory, and skin-protective properties, making them a subject of interest in anti-aging and skincare research.
References:
Hamilton-Miller JM. Antimicrobial properties of tea (Camellia sinensis L.). Antimicrob Agents Chemother. 1995;39(11):2375-2377.
Khan N, Mukhtar H. Tea polyphenols for health promotion. Life Sci. 2007;81(7):519-533.
Mandel S, Youdim MB. Catechin polyphenols: neurodegeneration and neuroprotection in neurodegenerative diseases. Free Radic Biol Med. 2004;37(3):304-17.
Jochmann N, Baumann G, Stangl V. Green tea and cardiovascular disease: from molecular targets towards human health. Curr Opin Clin Nutr Metab Care. 2008;11(6):758-765.
Post time: May-11-2024
