Want those beautiful produce purchases from Your Local Greengrocer to last longer? Look no further, here are 4 ways to preserve your produce!
Canning involves placing fruit and vegetables in airtight containers, typically glass jars, and so prevent bacteria getting to them. Canned good can be stored on shelves for years, if required. There are two methods, although one requires a specialist machine so may not be practical or cost-efficient for many people. This is the pressure canning method, which enables you to achieve temperatures above boiling point that foods with low acidity require to effectively neutralise the threat of the botulism bacteria remaining active. It requires a pressure canning machine and is the method used to can most vegetables, as they are low in acid. Fruit, being high in acid, does not have the threat of botulism, so can be canned using a simpler method. Just place your fruit in the jar, top with boiling water, leaving an inch or so of space at the top of the jar (to allow space for the fruit to expand), run a spatula around the inside edge to remove any air bubbles, then close with a threaded lid.
Whichever method you use, the jars must be sterilized before being filled. You can do this either by using sterilizing tablets such as those used for babies’ bottles, or by placing the jars (and their lids) in an oven on a low temperature for half and hour or so in order to kill all the bacteria.
One of the oldest methods of preserving food, salting can be used for meat and fish, as well as sliced vegetables. There are two methods. The first uses a low salt to vegetable ratio (between two and five percent salt per weight of vegetables). This level of salting promotes the growth of the lactic acid bacteria, which in turn inhibits the growth of other bacterial forms that could spoil the food. It also serves to slightly pickle the vegetables. The second method uses a higher percentage of salt (between twenty and twenty-five percent), preserving the freshness of the produce but adding a salty flavour when used, even after the salt has been washed off. Whichever method of salting you use, you need to store the produce in the refrigerator.
Drying dehydrates the fruit or vegetables, removing all the water along with the bacteria, yeasts and mold that live in the moisture. Besides altering the texture of the food, drying also modifies the taste, typically concentrating it. Dried food has the added benefit of being safe to store as is on your pantry shelf – you don’t need special packaging to keep it in or to keep it in the refrigerator. In some countries solar drying of food is a part of life, and if you live in an area that receives high levels of consistent sunshine, you may be able to dry food that way. More likely however, is drying in an oven. The technique requires low temperature and good air circulation so use the lowest setting and prop the oven door open – this allows the air that the moisture has evaporated into to escape.
Freezing fruit and vegetables soon after they are picked serves to ‘lock in’ the flavour and freshness of the produce. Freezing and then ways to preserve fruit thawing a vegetable or fruit is the preserving method that will have an end product that most closely resembles the taste of fresh food. You effectively place the food in suspended animation in whatever condition it is in when you freeze it, so always freeze ripe produce, and avoid spoiled specimens. You can freeze the produce in wax-coated cardboard containers, in plastic boxes or jars made with very thick glass. It is recommended that you blanch vegetables you are going to freeze in boiling water for a minute or so beforehand – this limits the activity of enzymes that may spoil the produce if stored over a long time. You need a temperature below freezing point for effective long-term storage, so use the freezer compartment in your refrigerator for food that you will use within a month, as temperatures in these rarely get down to the requisite zero degrees. When thawing food, leave at room temperature until completely thawed, rather than trying to thaw in the oven.