Ingredient

Cucumber

A cucumber is about ninety-six per cent water held in large, turgid cells, and almost every good and bad thing about it follows from that single fact. It is refreshing because of the water, it goes limp because of the water, and it turns a sandwich soggy because the water comes out the moment you salt or cut it.

The cucumbers you will meet

Long or English cucumber

The supermarket default, usually shrink-wrapped. Thin skin, few seeds, mild, very high water. Good raw, poor for pickling.

Ridge or field cucumber

Shorter, thicker-skinned, bumpier, more assertive in flavour. Common across Europe and the Middle East.

Mini or Lebanese cucumber

Small, thin-skinned, dense, crunchy and noticeably sweeter. The best for eating raw, and the shrink-wrap is unnecessary.

Pickling cucumber or gherkin

Small, firm, thick-skinned, low water. Bred specifically to survive brine without collapsing, and worth seeking out if you ferment.

Japanese cucumber

Slender, very crisp, almost seedless. Excellent in sunomono and smashed cucumber salads.

The water problem, and the two ways round it

Cut a cucumber and you have opened millions of cells full of water that is now free to leave. Add salt and osmosis pulls it out faster. In a salad that means a pool of liquid at the bottom within twenty minutes; in a sandwich it means bread that has gone translucent.

Salt it deliberately, in advance. Slice or chunk the cucumber, salt it, and leave it in a colander for twenty to thirty minutes, then drain and pat it dry. You have taken the water out on purpose and at a time of your choosing, and the result is a denser, more intensely cucumbery, seasoned piece of vegetable that will not water anything down. This is what a Greek salad, a tzatziki and a good cucumber sandwich all depend on.

Or deseed it. The seedy core is the wettest part by a distance. Halve it lengthways, run a teaspoon down the middle, and discard the core. Faster than salting, though it removes less water overall.

For tzatziki and raita in particular, grating and then squeezing the cucumber hard in a cloth is the step that separates a thick sauce from a thin one.

What to do with it

• Smashed cucumber. Bash it with the flat of a knife until it cracks apart, salt it, drain, then dress with garlic, vinegar, sesame oil and chilli. The rough torn surfaces hold dressing far better than clean slices, which is the whole point.
• Tzatziki, raita, cacık. Grated, salted, squeezed dry, into yoghurt with garlic, mint or dill.
• Greek salad, in thick half-moons rather than thin slices, so it stays crunchy against the tomato and feta.
• Quick-pickled, thinly sliced in vinegar, sugar and dill for half an hour. One of the best returns on effort in any kitchen.
• Fermented, if you have small firm ones — see fermented cucumbers.
• In a cold soup, blended with yoghurt, dill and a little garlic.
• Sandwiches, salted and dried first, on buttered bread — the butter is a moisture barrier and is doing a job.
• Briefly cooked, which surprises people. Cucumber sautéed in butter with dill is a genuine dish and goes very well with fish.

Buying and storing

Look for firm along the whole length. Cucumbers go soft from the ends inwards, so a specimen that is firm in the middle and yielding at the tips is already past its best. The skin should be taut rather than wrinkled, and a dull, slightly waxy bloom is normal.

Store them in the fridge, though not in the coldest part of it. Cucumbers suffer chilling injury at very low temperatures — the flesh goes translucent and pitted and softens quickly. The salad drawer is the right place.

Keep them away from apples, bananas and tomatoes, which give off ethylene and will yellow and soften a cucumber noticeably faster.

Once cut, wrap the cut face and use it within a couple of days. The exposed surface loses water fast and goes slimy.

Pickling, fermenting, and which to choose

The two things people mean by a pickled cucumber are different foods.

• A vinegar pickle is preserved by acid you added. Sharp, clean, predictable, and ready within a week. This is what a gherkin or a cornichon is.
• A ferment is preserved by lactic acid the cucumber made itself, over days in salt water. Sour rather than sharp, cloudy by design, and more complex.
• Cut off the blossom end — the end opposite the stalk — whichever you are making. Enzymes concentrated there soften pickles, and removing it is the single most effective thing you can do.
• Use small ridge or pickling cucumbers. Large salad cucumbers are bred for water content and go soft.
• A quick fridge pickle — thin slices in warm sweetened brine — takes an hour and needs no preserving skill at all.

Common questions