The bitter truth about this elusive flavour

In general. the darker the wine, the more pronounced the tannins. iStock/Getty Images Plus/givaga photo

When you hear someone talk about tannins in wine, they are talking about astringent sensory components that contribute to a wine’s structure and complexity. On the palate, they create a dry, puckering sensation on the palate, often perceived as a bitter taste.

Tannins are chemical compounds that belong to a larger group called polyphenols; they occur naturally in a large number of plants, including tea, cacao and grapes, as well as the wooden barrels used in the winemaking process.

Tannins have greater importance in red winemaking due to their contribution to red wine’s colour. While white wines are typically made by extracting grape juice at the start of the winemaking process and then disposing of the leftover materials, in red winemaking, the juice spends an extended period in contact with the tannin-rich grape skins, seeds and stems, drawing colour, flavour and texture from them.

Tannins shape a wine’s structure, aging potential and overall sensory character in profound and often underappreciated ways. One fascinating aspect of tannins is their ability to bind with proteins, producing a dry, grippy sensation in the mouth. This interaction cleanses the palate, making tannic wines ideal companions to rich, fatty foods. The classic pairing of tannic Cabernet Sauvignon with a succulent steak perfectly demonstrates this.

The expression of tannins varies widely depending on the grape variety, winemaking technique and aging process. Grapes like Cabernet Sauvignon, Sangiovese and Tannat are known for their robust, mouth-coating tannins. Skin contact during fermentation is a critical factor in tannin extraction. It is also evident in the creation of orange wines, where extended contact with grape skins infuses white wines with tannins, enhancing structure and complexity.

Winemakers can adjust tannin levels through maceration duration, fermentation temperature and oak aging. Barrel aging introduces additional tannins from the wood, further enhancing the wine’s structure and depth. As wines age, tannins transform, becoming softer and more integrated, turning a once abrasive young wine into a silky, harmonious experience.

The next time you enjoy a glass of wine, consider the influence of tannins. These compounds are the unsung heroes responsible for crafting a wine’s texture, balance and aging potential, shaping every memorable sip you take.

THREE TO TRY

Garzon Reserva Tannat 2018
(Uruguay, $26)
Plum, blackberry, raspberry. Full-bodied, mature, integrated tannins.

Township 7 Vineyards and Winery Cabernet Sauvignon 2021
(Okanagan Valley, $34)
Cassis, dark cherry, cedar. Rich fruit, velvety tannins, textured profile.

Cecchi Storia di Famiglia Chianti Classico 2019
(Chianti, Italy, $22)
Cherry, chocolate, violet undertones. Ripe, round tannins.

Christine Campbell

Christine Campbell is a Vancouver-based freelance and travel writer, educator and host of the Wine Soundtrack Canada podcast. She is WSET certified and is a French Wine Scholar. Follow Christine’s adventures in wine and abroad at girlsgogrape.com and on Instagram at @girlsgograpedotcom.