Stuart Bale of Crucible – London’s laboratory and creative hub for bartenders – explains how to create drinks with viscosity, grip, body and burn.

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It’s what separates a drink that feels alive from one that tastes like flavoured water. The taste and flavour of a drink is only part of the story and you can really elevate an otherwise average-tasting drink to an exceptional drinking experience by considering and manipulating these other aspects. For non-alcoholic drinks in particular, it’s the make-or-break detail. Alcohol naturally brings texture and weight, so if you take it away, you need to find other ways to give a liquid depth.

You can think of mouthfeel as comprising a few parts:

- Viscosity

- Grip

- Body

- Burn

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Viscosity

This one often gets linked straight to sweetness. More sugar means a thicker texture, which makes the drink feel richer. 

But sugar isn’t the only way to get there. There are plenty of ingredients that give you that same lush texture without piling on the sweetness. Vegetable glycerine is one of the best examples. It’s a sugar alcohol that’s often used to give vodka a rounder mouthfeel. Hydrocolloids like carrageenan or pectin are also brilliant for this because they dissolve easily in water and don’t leave much flavour behind.

Some handy tools for viscosity:

- Vegetable glycerine

- Carrageenan

- Xanthan gum

- Locust bean gum

- Gum arabic

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Grip

Red wine is the classic example of grip. That dry, slightly pulling sensation on the sides of your mouth comes from tannins.

Tannins are polyphenolic compounds that react with a protein in your saliva called mucin. Mucin is what keeps your mouth lubricated. When tannins meet mucin, they strip some of that away, leaving your mouth dry. That’s grip – or abrasion is another appropriate word for the sensation. (Tannin also reacts with the same slippery proteins found in fish. Scientists in China actually made fishing gloves using tannin-like compounds so the fish don’t slip out of your hands. Smart stuff.)

Tannins show up all over the place: unripe fruit, wine, tea, coffee, even cocoa. They don’t distil well because of their high melting point, so if you want that sensation in a drink, you have to extract it or add tannic acid directly.

A few main tannin types and where they show up:

- Gallic acid – rhubarb, witch hazel, oak, sumac

- Flavan-3-ols – teas, acacia, cocoa

- Chlorogenic acid – coffee, maté

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Body

The easiest way to add body is carbonation. It’s often underrated, but bubbles can completely change how a drink feels and smells. Carbon dioxide lifts volatile aromas and adds a subtle acidity from the carbonic acid it forms in water. Those tiny bubbles sneak between flavour molecules, lifting the aromatics and making the drink feel more alive. When done right, carbonation doesn’t just make something fizzy – it gives the drink presence.

Some more advanced ways of physically affecting the body of the drink include using hydrocolloids to create airs or emulsions. Depending on your desired outcome, there is a wide variety of these, such as lecithin to get a very light sort of foam texture. There is a spectacular free resource on this subject called Texture, on the website khymos.org.

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Burn

Whether we like to admit it or not, one of the defining features of cocktails is that burn you feel when you drink them. Every alcohol drinker recognises it. Most even enjoy it, though few really understand what’s going on. It’s a very particular kind of heat. Sharp, quick to fade, and somehow less noticeable in more complex spirits. The higher the abv, the more it tends to show up.

The story starts with a receptor called VR1, which lives in your mouth and throat. When you eat something hot, VR1 fires a signal to your brain that says “this is burning”.  Capsaicin, the compound that makes chillies spicy, talks directly to those receptors. Ethanol does too, but in its own way. Instead of triggering them, it makes them more sensitive.

Normally, VR1 switches on around 41°C. Ethanol lowers that to about 33°C. Since your body sits around 37.5°C, you can see where this is going. 

The receptors start firing just from contact, because your own body heat now feels “too hot” to them. That’s the burn.

Particularly in low or no-alcohol drinks, we need to trick the mouth into thinking that the liquid in it is more “interesting” for the brain. A few chemicals we can use to do that are:

- Capsaicin – chilli

- Allyl isothiocyanate – horseradish, wasabi

- Gingerol – ginger

Used carefully, these can bring that same warm, lingering finish that makes a drink feel complete.