Why Berries Turn Into One Solid Block

There is nothing sadder than reaching into the freezer in January for a handful of raspberries and finding a single, frostbitten lump the size of a house brick. You chip at it with a knife, the berries smash, and by the time you have what you need the rest has thawed and gone soft. That happens because the fruit was frozen in a bag, all pressed together, so the berries froze into each other as one mass.

The fix is simple and takes very little extra effort. Freeze the berries separately first — spread out on a tray — and then bag them once they are solid. Each berry stays loose and separate, so you can pour out exactly what you need and put the rest straight back. Cooks call it open freezing or tray freezing; we just call it the way to keep summer in the freezer properly.

Pick, Sort and Dry

Quality in, quality out. A berry that was going soft on the bush will be disappointing in December, so be ruthless at this stage.

• Pick in the cool of the morning if you can, when the fruit is firm and fully coloured. Wet, warm berries bruise and freeze poorly.
• Sort as you go. Eat the squashed ones, compost the mouldy ones, and freeze only sound fruit.
• Wash only if you must. If the berries are dusty or you have been spraying nearby, rinse them quickly in a bowl of cold water and drain well.
• Dry thoroughly. Spread on a clean tea towel or kitchen paper and leave until any surface moisture has gone. Wet berries freeze into a solid sheet and taste watery later.
• Prepare them properly: hull strawberries and halve any that are large, top and tail gooseberries and redcurrants, string blackcurrants if you have the patience.

Work in small batches too. A kilo of raspberries left sitting in a bowl while you deal with the next punnet will start to collapse under its own weight.

The Tray Freeze

Line a flat baking tray or two with baking parchment. Spread the prepared berries in a single layer, leaving a little space between them so they do not touch. Do not pile them up, and do not be tempted to squeeze more on — it defeats the whole exercise.

Slide the trays into the coldest part of the freezer and leave for two to four hours, until every berry is hard right through. If your freezer is packed, give it longer. A good test is to shake the tray gently: the berries should rattle and roll freely, like little marbles. If any are still soft or sticky, put them back.

A word on temperature. Most freezers sit around -18°C, which is exactly right for this job. Faster freezing means smaller ice crystals, which means less damage to the cell walls and a better texture when the berries thaw. If your freezer has a fast-freeze setting, use it.

Bagging, Labelling and Storing

Once the berries are solid, tip them into freezer bags or lidded containers. Work quickly so they do not begin to thaw on the worktop.

• Bag in usable portions — enough for a crumble, a batch of jam, or a week of porridge. You will thank yourself later.
• Squeeze out the air before sealing, or use a rigid container with as little headspace as possible. Air is the enemy of flavour.
• Label everything with the fruit, the variety if you know it, and the date. A mixed bag of "red things, July" tells you nothing come February.
• Store flat so the bags stack neatly and you can see what you have.

Most berries keep well for eight to twelve months. Raspberries, strawberries and blackberries are best used within eight or nine months; blackcurrants, redcurrants and gooseberries will happily go a year. Never refreeze fruit that has already thawed.

Notes by Berry

Different fruits behave differently, and it is worth knowing which ones hold their shape.

• Strawberries soften most of all. Freeze them whole, hulled, or halved if large. They are superb for smoothies, coulis and ice cream, but will not look pristine in a fruit salad.
• Raspberries and blackberries freeze beautifully and keep their shape well. Handle them as little as possible — they bruise if you look at them too hard.
• Blueberries are the easiest of the lot and freeze like tiny marbles. Excellent straight from frozen in porridge or muffins.
• Blackcurrants, redcurrants and gooseberries are the backbone of winter puddings and jams. Their high acid content means they freeze and keep superbly.
• Cherries should be stoned first unless you enjoy surprises in your pie. Freeze them on the tray in the same way.

Cooking With Them Later

This is the real reward. Because the berries are loose, you can take out a handful at a time and return the bag to the freezer immediately.

For crumbles and pies, use them straight from frozen and add five to ten minutes to the cooking time. For compotes and coulis, tip them into a pan with a spoonful of water and a little sugar and warm gently — no need to thaw first. For jam, frozen fruit is often better than fresh, because the freezing breaks down the cell walls and the fruit releases its juice more readily. A handful stirred into yoghurt or overnight oats in the morning is a small, bright reminder of a warm afternoon in July.

Thawed berries will release juice, so if you want them for the top of a pavlova, thaw them in a sieve over a bowl and use the collected juice in a dressing or a glass of fizzy water. Taste before you sweeten — good summer fruit needs far less sugar than you might think.