Ingredient

Raspberry

A raspberry comes away from its core when picked, which leaves it hollow, and that hollowness is the whole story of the fruit: it is why they crush under their own weight, why they mould within days, and why they release their juice so readily into a pan.

The hollow fruit

A blackberry keeps its core; a raspberry leaves it behind on the cane. What you buy is a thimble of tiny individual drupelets held together by nothing much, with a cavity in the middle. It has almost no structural strength.

That is why the bottom layer of a punnet is usually crushed, why they cannot be washed under a running tap, and why they are one of the few fruits genuinely better bought frozen if you are cooking them.

It is also why they cook so fast. Heat a pan of raspberries with sugar and they collapse into sauce in under two minutes — there is no cell structure to hold out.

Why raspberry jam works

Of the common jam fruits, this is the forgiving one.

Good pectin

Moderate to high, particularly in slightly under-ripe fruit. Enough to set without additions in most recipes.

Good acid

Naturally sharp, which is exactly the condition pectin needs. Most recipes need no added lemon.

Fast

Because the fruit breaks down almost immediately, the boil is short and the fresh flavour survives. A raspberry jam can be finished in fifteen minutes.

The seeds

Numerous and hard. Sieving half the pulp and leaving half gives a jam with body and fewer seeds; sieving all of it gives a jelly.

Frozen fruit

Works perfectly. Freeze a glut and make jam in the winter, when standing over a hot pan is less of a punishment.

Beyond jam

• Crushed raw with sugar over ice cream, which takes a minute and is better than any bought sauce.
• Into a vinegar. Raspberry vinegar — fruit steeped in white wine vinegar, then strained and sweetened — is an old British preparation and excellent in a dressing.
• Folded through a cranachan with oats, cream, honey and whisky. The oats are toasted, which matters.
• A coulis, simply sieved raw with icing sugar and a squeeze of lemon. No cooking at all.
• With game or duck, where the sharpness cuts fat. Deglaze the pan with a few crushed berries and a splash of vinegar.
• Frozen straight into a smoothie, where their tendency to collapse is an advantage.

Handling a punnet

These need more care than any other common berry.

1. Tip them gently onto a tray rather than picking them out one at a time. Fingers crush them.
2. Discard any showing a grey fuzz immediately, and the ones touching it.
3. Do not wash unless you must. If you do, float them briefly in a bowl of cold water and lift them out with your hands, never pour them into a colander under a tap.
4. Dry on kitchen paper before refrigerating, in a single layer.
5. To freeze, spread on a tray, freeze until solid, then bag. Frozen loose they stay separate; bagged wet they fuse.

Common questions