Tannins: you’ve probably heard of them, especially if you enjoy a glass of red wine, but you may not know about their vital role in the art of winemaking. In their early stages they’re very bitter, and eventually they may well end up as sediment in the bottom of your wine glass – but what they do in the middle is just a little bit magical…
What are tannins
Tannins are clever little chemical compounds that Mother Nature has developed to stop animals from eating underripe fruit, veg and tree bark. They taste very bitter and dry. If you’ve ever inadvertently crunched on the seeds of a grape, you’ll know how those raw, young tannins feel – like your tongue is trying to contract!
Every time you have a sip of wine that creates a drying – or “astringent” – sensation in your mouth, you’re experiencing the effect of tannins. . Other common places you’ll find that tannic sensation are in over-steeped tea leaves, the skins of whole nuts like walnuts and almonds, coffee, dark chocolate, and whole spices like cloves.
Scientifically speaking, they’re chemical compounds that are a type of polyphenol, and they crop up all over the place in the natural world – in leaves and stalks, and in seeds and fruit skins, which is why they can also be found in wine.
Why does wine contain tannins?
The process of winemaking – especially red winemaking – means that tannins almost always find their way into a bottle. Tannins are present in grape skins, seeds and stems, so whenever they are present in fermentation, the tannins will be released into the wine as part of that process. The longer the skins and pips soak – or macerate – together in the alcohol as it’s produced, the more tannic the end product will be.
Winemaking style has a direct influence on how much tannin finds its way into a wine. The temperature chosen for fermentation, the amount of time the skins stay in with the juice (the maceration time), the number of times the grapes are pushed through the process (punch-downs) and the force that’s used – all of these things will affect the amount of tannin that goes into the finished article.
Wines produced on a bigger scale will probably have softer, more rounded tannin flavours, simply because their methods of production mean that the juice spends less time with the tannin-rich influences.
It’s also worth remembering that wood contains tannins – so the barrel in which a wine is ageing is also likely to pass on its tannins and their inherent flavours and aromas.
Sometimes – but not always – tannins evolve during the maturing process to become sediment, which may lie in wait at the bottom of a bottle to trap the unwary. This is why it’s a good idea to decant your older wines before pouring into glasses.
Which wines have tannins?
Red wines will always have tannins, because of the way they are produced to create the red colour – using the grape skins, which contain the tannins. It’s the level of tannin that can vary in different reds, rather than whether it’s there at all. Some high-tannin reds include Sagrantino and Nebbiolo from Italy, Monastrell from Spain and France, and most famously, Cabernet Sauvignon from anywhere in the world.
White and rose wines can also contain tannins, though – don’t assume that they won’t. Those tannins will often come from their time spent in aging barrels, from the wood, rather than the fruit skins, because the maceration times are much shorter. They usually have lower tannin levels than a red as a result – but white wines can also be produced with extended skin and pip fermentation, which gives similar levels of tannin to a red. This is often known as “orange wine”.
Try some wines with balanced tannins
Are tannins good or bad in wine?
If you drink a high-tannin wine when it’s young, you’ll certainly know it – your mouth will feel like the Sahara and you may feel the urge to dive for the plush comfort of a Merlot instead! But that very dryness is one of the most important players in creating a beautifully-aged wine: a wine that can lie for decades before coming into its own.
This is because tannins need time to work their magic. Those bitter polyphenols will change and join, smoothing out their texture and softening their taste, enriching the aroma and texture. And as antioxidants, they protect the wine as it ages, as well as enhancing the taste – and giving you health benefits as the drinker, as well…
How do tannins in wine affect the body?
A good number of studies have shown that wine tannins are likely to be good for your health, especially with their antioxidant properties. This is why you may have heard that having a glass of red wine a day can be beneficial, as can dark chocolate and black tea – it’s those tannins.
However, some people do report less than desirable effects. Tannins have been known to contribute to acid reflux, in the same way as coffee can. Tannins can weaken the valve between your oesophagus and stomach, causing that acid to rise and give you heartburn. In large quantities, or if you’re prone to it, tannins may also cause irritation to the stomach and lead to nausea, vomiting and diarrhoea – which can also be exacerbated by high quantities of sugar.
There is also some evidence to suggest that tannins can be a cause of migraine headaches. The best way to test this is to cut all tannins out of your diet and see whether that helps – and if so, stick to low-tannin whites to enjoy a glass instead.
Overall though, if you’re not prone to tannin migraines, a sensitive stomach or heartburn – and take your red wine in moderation – there is every reason to believe that those tannins are doing you good.
Which foods work well with High Tannin wines?
When you’re drinking a high-tannin wine – whether it’s a young, dry one or a more velvety mature one – its astringency makes it the perfect companion to richer, fattier foods such as a marbled steak, with strong accompaniments like extra-virgin olive oil and black pepper. True scientific magic occurs between the food and wine, all brought about by those tannins – they will bind onto the meat proteins and make space for the more subtle flavours from both meat and wine to emerge. So taking them together means you’ll actually taste more than you would from consuming each element alone. Isn’t that amazing?
If you’d like to try this magic for yourself, we’ve a range of high-tannin big-hitters for your enjoyment – browse here: