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How to Preserve Food at Home
Natural Preservatives: Preserving Your Own Fruits and Vegetables
Traditionally, salt, sugar, vinegar, alcohol and oil and fat make the best natural preservatives to help you preserve your fruit and vegetables at home. These natural preservatives are suitable to make pickles such as pickled gherkins, relished and sauces and also oily fish, such as rollmops. Preserved fruit makes delicious jams and jellies, fruit cheeses and butters, and crystallized fruits. You can also preserve Parma ham, salt cod, sauerkraut, olives and lemons. Generally, home preserving using these natural preservatives produces superior results and more flavour than shop-bought items using modern preservatives.
The types of food you can preserve using salt
Salt (sodium chloride) is the most important preservative. In concentrated solutions it draws out the moisture in food, which stops micro-organisms growing. The higher the concentration of salt, the greater its preserving powers and the longer the food keeps.
Salt is used to preserve vegetables, fish, meat, and sometimes fruit. You can salt Parma ham, salt cod, gravadlax, sauerkraut, olives and lemons.
The types of salt you should be using to preserve food are:
· Sea salt and unrefined rock salt
· Curing salt - especially good for curing meat
NOTE: Ordinary table salt contains added anti-caking agents and so is not suitable for preserving
The types of food you can preserve using sugar
In concentrations higher than 60%, sugar is as powerful a preservative as salt. Like salt, it draws out the moisture in foods and the higher the sugar content, the longer it keeps the food.
Sugar is mainly used to preserve fruit, although, when combined with vinegar, it is used in fruit and vegetable mixtures such as chutneys. You can also confidently make jams, jellies, fruit cheeses and butters, and crystallized fruits.
The types of sugar you should be using to preserve food are:
- Cane, granulated cane, sugar beet and golden unrefined sugars
- Dark brown and molasses sugars are good for chutneys and some marmalades but not for sweet preserves
- Jam sugar contains added pectin and is used especially for low-pectin fruits such as blackcurrants, crab apples, gooseberries, plums and citrus fruits.
- Caster sugar is finer than granulated sugar and dissolves more readily so it is useful for making syrups and cordials.
- Preserving sugar - a type of sugar which produces less froth and scum, but is not essential for preserving, just more convenient to use
The types of food you can preserve using oils and fats
Oils and animal fats provide a protective seal for foods, thus preventing contact with air. Neither are strictly preserving agents so foods must be preserved first. Meat must be salted first to lose moisture, and vegetables are cooked in an acid, such as a vinegar solution before being preserved with oils and fats. Meat, vegetables and feta cheese are best preserved using these natural preservatives.
The types of oil and fat you should be using to preserve food are:
- Olive oil, butter, duck and goose fat, and lard
- Sunflower, grape and rapeseed oil
NOTE: The flavours of beef and lamb fat are too strong to be used for preserving and will produce and unpleasant taste.
The types of food you can preserve using alcohol
Pure alcohol is the most powerful preserving agent of all: it kills all microorganisms and any food preserved in it will deep indefinitely. No other form of processing is required.
Fruits do very well in alcohol; you can easily make sloe gin, cherries in brandy and rumtopf.
The types of alcohol you should be using to preserve food are:
- Brandy, Eau-de-vie, gin, rum, vodka and whisky
NOTE: Wine, beer and fortified wines are not strong enough to preserve foods effectively on their own.
The types of food you can preserve using vinegar
Like salt, vinegar has been used for preserving food as savoury preserves for centuries. Made by fermenting alcohol to produce acetic acid, and its acidity prevents or inhibits the growth of most of micro-organisms, including e-coli, that spoil food. To be effective, the vinegar must contain at least 5% acetic acid.
Vinegar is mainly used for preserving vegetables as pickles, relishes and sauces, and oily fish.
The types of vinegar you should be using to preserve food are:
- Malt (strong brown), distilled and spirit (colourless malt) vinegar, wine and cider vinegars
- Pickling vinegar
NOTE: Balsamic vinegar is used as a flavouring only, and rice vinegar, though suitable for preserving, has the mildest flavor and preserving strength.
Essential equipment you will need to preserve food in your home
Most equipment for preserving can be found in any kitchen but a few items you might not have readily available are needed for a particular preserving method or specialist tasks.
Small ladle - invaluable for potting up hot sweet and savoury preserves and bottled fruits.
Slotted spoon - useful for poaching fruit in a syrup or vegetables in vinegar. Use a skimmer to skim cum off sweet preserves
Wooden spoon - large to stir jams and chutneys
Jam (sugar) thermometer - useful for jams and marmalades as it igives an accurate temperature for the setting point
Wide-mouthed jam funnel - Buy non-reactive stainless steel funnels. Use to prevent the spillage of sweet and savoury preserves when potting them up.
Long-spouted funnel - choose non-reactive stainless steel or plastic funnels for bottling drinks, ketchups and sauces.
Sturdy cheesecloth/calico straining bag - use for filtering and straining produce for home brews. Hang it up by it handles.
Jelly bag - ideal for straining jellies and smaller quantities of liquids such as cordials. To clean the bag turn inside out, soak in hot water, and then wash immediately.
Muslin cloth - use with a sieve as a makeshift jelly bag to wrap around hams and bacon, and to cover fermenting foods.
Domestic stainless steel smoker - purpose-built smoker with a drip tray and cover for hot smoking foods indoors and outside.
Stainless steel preserving pan - the thick, heavy base of this specialist pan ensures even heat distribution while its wide sides allow for rapid boiling. It is ideal for making large quantities of jams, jellies, marmalades, chutneys, and other preserves.
Wok - a wok with a rack and a glass lid makes an ideal instant hot smoker.
Demijohn, airlock and siphon - these 3 basic pieces of equipment are essential for brewing. Use a demijohn to store the fermenting brew and plug its narrow neck with an airlock, which controls the pressure in the demijohn. Use a siphon to transfer the brew into bottles. Also useful is a hydrometer to check the gravity, or density, of the liquid, and litmus papers to test its acidity or alkalinity.
Sausage-making kit - this kit has a mincer and nozzle for filling casings to make sausage-making easy. Electric versions are also available.