Tannin is one of the fundamental building blocks of red wine, influencing everything from texture and structure to ageing potential and food compatibility. We've asked Assistant Winemaker, Gareth Hogan, to offer some expert guidance on this often misunderstood aspect of red wine.

What Is Tannin?

Tannins are one of the most important structural components of wine. They influence texture, ageing potential, and the overall balance of what you taste in the glass.

From a technical perspective, tannins are polyphenolic compounds extracted from grape skins, seeds, and stems during maceration. In red winemaking, maceration occurs alongside fermentation, which is why tannins are such a defining feature of red wines. White wines, by contrast, are generally pressed directly off their skins and undergo little to no maceration, resulting in much lower tannin levels.

How Does Tannin Feel?

A simple way to understand tannins is to think of tea. If you've ever left a tea bag steeping for too long and noticed a drying, grippy sensation in your mouth, you've experienced tannins at work.

Tannins can be described in countless ways: fine, chalky, dusty, coarse, chunky, silky, powdery, velvety, polished, grainy, rounded - the list goes on. Some of these descriptors may make tannin sound undesirable, but as with all things in wine, balance is what matters most.

Where Does Tannin Come From?

It is certainly possible to make red wines with minimal or barely perceptible tannins. Rosé is perhaps the most extreme example: red grapes vinified more like a white wine. However, as soon as red grapes spend time in contact with their skins, polyphenolic compounds begin to enter the wine, influencing not only tannin but also colour, texture, and overall structure.

The amount of tannin extracted depends largely on the duration of maceration. Interestingly, tannin extraction does not increase indefinitely in a straight line. Given enough time, these compounds begin to bind together, forming larger molecules that eventually become too heavy to remain suspended in the wine. They settle out, creating a bell-curve effect rather than a continual increase in tannin.

Tannin and Ageing

If you've ever opened an old bottle of red wine and found sediment at the bottom, you've seen this same process in action. Tannin is one of the reasons wine feels alive and evolves over time - it is part of a slow, ongoing series of chemical reactions that continue long after the wine is bottled.

The character of tannin is influenced by a range of factors, including grape variety, ripeness, climate, soil, and topography. Oak can also contribute to the perception of tannin, although most winemakers aim for this influence to remain subtle and integrated.

We want the benefits of maceration - depth, density, and concentration - without excessive bitterness or astringency. The goal is a wine that is enjoyable in its youth while also rewarding those willing to cellar it.

Every vintage presents a different challenge, and a new opportunity to fine-tune that balance.