4 Ways to Preserve Food
September is the perfect time of year to have a go at preserving food.
The glut of produce from Summer and early Autumn can be preserved using 4 techniques so that they can last through to the Winter.
Once you have the basic techniques and recipes to hand, you can experiment with whatever produce you have available from your garden or allotment. The results even make fantastic (and cheap!) gifts for Christmas.
Here are our 4 go-to preservation methods for fruit and veg. There are several other techniques, for example freezing, curing or smoking, which can be applied to other kinds of food.
By cooking fruit with sugar, the mixture reduces in water content, thickens, and becomes an inhospitable place for bacteria to grow. This makes sugaring ideal for preserving food.
Flavours also intensify, and there are numerous fruit combinations to try out throughout the year, as well as several methods of sugar preservation. Here are a few of our favourites:
- Compotes: a combination of fruit and a sugar syrup. Compotes are runnier and generally chunkier than jam and require less cooking time. You can add liquor, juices and spices for more complex flavours. They keep in the fridge for 2 weeks. Here’s our recipe for Blackberry & Orange Compote.
- Jams: by taking fruit to the boil, jamming reduces the fruit’s moisture content and kills bacteria. The high sugar content prevents bacteria regrowth, and sealing in an air-tight, sterilised jar, prevents re-contamination. Jam is a thick mixture, with small pieces of fruit, and should spread easily. Here’s our recipe for Blackberry & Apple Jam.
- Curds: not strictly a preserve, but an alternative way of using autumnal fruits if you’ve made too many jams. Fruit curds are generally made from citrus fruits, predominantly lemon, but it’s worth trying out other fruits, such as gooseberries, quince, apricots and apples. Curds have a velvety texture, due to the addition of eggs and butter. You can use curds in cakes, tarts, cheesecakes, and swirled into ice cream. Here’s our recipe for Apple & Lemon Curd.
- Preserves: contain large pieces of fruit. Here’s our recipe for Quince Preserve.
- Conserves: contain a combination of fruit, nuts, dried fruit, spices and citrus.
- Marmalade: contains citrus.
- Jelly: fruit and sugar strained overnight to give a clear liquid so no fruit solids remain.
Top Tips for Jam:
- Start on a low heat, then turn up to reach boiling. Don’t go to high heat straight away.
- Use granulated sugar as it dissolves more slowly as it is coarser than caster sugar. This gives jams more clarity.
- Add a knob of butter to the jam at the end of cooking, as it collects the foam on the top.
- Use a preserving pan if you can, especially for large quantities, as the shape allows the water to escape faster, bringing the pectin molecules together quickly. Jam can take between 5 to 20 minutes depending on the fruit and pan used. If you don’t have a preserving pan, just use a large pan so the fruit cooks evenly.
- Weigh the sugar for jam recipes, as too much can cause crystallisation.
- Jam is cooked once it reaches 104 degrees celsius. If you do not have a jam thermometer, place a saucer in the freezer for 3 minutes, and then take it out and place a blob of jam on the plate. If the jam wrinkles when pushed, it is done.
- Pectin is a key component of jam making. It is a naturally occurring carbohydrate with thickening and gelling properties. Fruit such as apples and blackberries have natural pectin, with the highest concentrations in the skins, cores and seeds. The role of pectin is to reduce cooking time, retaining as much fresh flavour as possible, retain natural colour, and give a better texture.
- A general rule of thumb is a rough 1 to 1 ratio between sugar and fruit mass.
- After cooking jam, soak your pans using boiling water immediately, to make washing up a lot easier.
Salt is applied to vegetables first to draw out the moisture, before picking takes place. The vegetables are then drained and patted dry, and added to a pickling liquor made of vinegar, sugar and spices.
When preserving food using the pickling method, use a vinegar of at least 5% acidity to ensure a successful pickling process.
The result is a sharp, crunchy assortment of vegetables which keep well for weeks. Most vegetables can be pickled in some form or another. We love pickled courgettes and the accompanying red onions which turn a vibrant pinky purple after contact with vinegar.
Chutneys originated in India, and now are very popular in the UK. The possibilities for sweet or savoury chutneys are endless, and you can add a variety of herbs, spices and dried fruit to liven up the flavour. They are also great for using up misshapen, bruised or over-ripe produce.
Allowing chutneys to mature for 1-2 weeks, even a month, before eating gives the chutney a deeper, richer flavour.
Ingredients in chutneys are cooked slowly until the excess water has evaporated. Like pickling, the natural preservatives used in chutneys are vinegar and sugar.
Types of vinegar to use in chutneys include malt, white wine, red wine or cider vinegar, of at least 5% acidity. This prevents growth of bacteria and mould, as well as the extraction of excess moisture from cooking.
We love versatile chutneys that can be enjoyed as part of a cheese board, layered in a luxury toastie, doubling as a burger relish and even jarred up for early Christmas presents. Enjoying a bit of heat is part of embracing the spice of life, so a Spicy Tomato Chutney recipe could be for you.
Bacteria loves moisture, so removing the water content from produce allows it to last much longer. The flavour also intensifies in dried fruit and veg, as well as reducing in size, making it easy to store.
It is easy to dry most produce if you have an oven set at a low heat. Simply slice thinly, lay out onto a baking tray and then store the dried foods in an airtight container afterward.
Storing your Preserved Foods
Your jars should be made of glass and the metal lid should have a plastic coating on the underside to prevent corroding from the vinegar from pickles or chutneys. Alternatively, use waxed discs of paper to seal.
Sterilising jars – Wash your jars and lids in hot, soapy water and then rinse thoroughly, or put them through the hot cycle in the dishwasher. Invert the jars onto a baking tray and put in the oven to dry for 15 minutes at a low heat.
Filling jars – Remove the hot jars with care from the oven. Be careful not to get your fingers in the jars, as you don’t want any bacteria getting into them. Immediately ladle your hot preserve into the jars (as the temperature starts to drop the likelihood of bacteria forming increases). It is important to remember to fill the jars as full as possible, not leaving any gaps.
Covering and sealing jars – Cover the jars once you have filled them. Once the jars have cooled down, recheck the seals and tighten the lids to prevent any air entering and causing mould formation.
Storage – Keep your unopened preserves in a cool, dark, dry place. Sunlight can have an effect on the colour and humid places may cause fermentation. Once opened store in the fridge and use within four weeks.