Preservation of fruits and vegetables for the winter: best techniques for you
The preservation of fruits and vegetables for winter is a need that has been handed down for a multitude of generations.
Among the most used methods we have jams, drying, curing with salt, pickling, oil-packing or freezing.
By using one of these methods we are actually doing two things: we are destroying endogenous enzymes and we are creating the worst environment for the proliferation of microorganisms, both responsible for the deterioration of fruits or vegetables, in order to make sure we can consume them for many more months ahead. Those who are fortunate enough to grow their own fruits and vegetables have one more reason (besides the gastronomic ones) to learn the art of preservation: to avoid food waste, a threat to the entire food production chain (read here about the immense waste that humanity creates), responsible for turning 30% of all food produced worldwide into “garbage”.
So if you want to be part of the solution, you must be familiar with at least one of the techniques for preserving fruits and vegetables. But which one?
It would be the best home method to safeguard the levels of vitamins, minerals and antioxidants; especially for vegetables!
However, apart from some types of fruit such as blueberries, blackberries, avocados (see here how you can freeze it without taking up too much space), said technique does not allow to obtain a final product with ideal organoleptic characteristics. But it is the easiest thing to do: that is to wash, dry and put the fruit or vegetables inside special resealable bags and put everything in the freezer compartment; or just blanch the vegetables, let them cool, dry and finally freeze them already portioned.
Jams and marmalades
They are perfect as a final result, very resistant (if done well) both before and after opening the lid (even if you have to keep them in the fridge). Unfortunately, apart from the deterioration of most of the vitamins, minerals and antioxidants due to the initial heat treatment, they hide another handicap: they are full of sugars!
Sugars are the favorite food of our cells, but the simple ones (let’s call them added sugars like those in our jam), are really useless: all ingested carbohydrates become sugars in the body.
Agreed, the topic is not healthy eating but fruit preservation for winter; so I admit it is the most popular and most appreciated method for breakfasts.
If you’re a frequent user of jams, at least cross them off your shopping list, and try making them at home. It doesn’t take much: wash, pit and, if you want, cut the fruit; cook it with sugar (equal to half the weight of the fruit) for about 1-2 hours and pour it boiling hot into well-washed jars; close with new, clean lids, turn them upside down to create a vacuum and wait for complete cooling. Now you can enjoy your creations all winter long.
This is one of my favorite techniques: you don’t need jars, sugar or salt, and the shape remains almost similar to the original fruit or vegetable, plus you can do it without using energy!
In many countries, summer UVB rays are more than enough to dry and thus preserve most fruits and vegetables, and even herbs. This totally natural and sustainable technique requires particular attention to avoid the growth of mold: the cause of major problems such as the dreaded Aflotoxin, recognized carcinogenic. Therefore continuous vigilance and proper ventilation is mandatory during the drying process.
Use a strong needle and thread and “create a necklace”, for example with cut peppers, cleaned from seeds and white veins: then hang it in a sunny place.
In 4-7 days and you will have got the peppers or eggplant or okra dried for the whole winter.
Curing with salt
For particularly watery fruits and vegetables such as tomatoes, in addition to the heat of the sun, the use of salt becomes mandatory.
Wash and cut the tomatoes in 2 or 3 slices (it depends on the size of the tomato); cover the surface with coarse salt (about half a teaspoon for the first side of the slice) and place in the sun on a clean surface (it is better to use a grid).
The next day turn the slices over to expose the other side to the sun, this time covering this side with salt.
At night bring them inside the house and in the morning put them back in the sun for the next 5-8 days. For those who live in very humid places, this method is not advisable; in this case the help of the oven is a must: 12 hours at 60 degrees… and always pay attention to mold; check each slice one by one.
Keep raw or cook the vegetables you need to preserve, such as peppers, eggplant, capers or whatever, in a solution of water, salt and white wine vinegar (I use half water, half vinegar).
Let them blanch and then place them in well-washed jars with new, equally clean caps.
Fill the jars with vinegar and flavorings; then pasteurize the jars in a pan in a bain-marie, following the advice of the Italian Ministry of Health that I report below, and store them in the dark for the winter.
The result is delicious without any hesitation, but can be very expensive (if you use a good oil) and equally caloric.
For the preparation I share here the advice of the Italian Ministry of Health taking into account the risk of Botulinum:
“…After being selected, washed and possibly cut, the vegetables must be blanched for a few minutes in a solution of water and vinegar in equal parts. In this way, besides cooking, they will be acidified and they will be safely preserved. It is recommended to use wine vinegar having an acidity equal or higher than 6%. In case a non wine vinegar is used, with an acidity equal to 5%, it is advisable not to dilute it in water, but to use it as it is.
Cooking of vegetables must not be prolonged, they must be “al dente”, otherwise they will completely lose consistency during storage. In case, besides vegetables, spices and aromatic herbs are used, they must also be blanched in water and vinegar. Once the cooking is over, they must be coarsely drained and allowed to cool and dry on a clean and dry cloth, then put them in the container making sure to fill all the empty spaces, without however crushing them too much. Once filled, cover completely with oil and try to remove any air still trapped in the food, using a plastic spatula. Then place a spacer and close the jar. Proceed with the pasteurization process which will last longer the bigger the jar is and will also vary according to the type of product prepared.
In case there are no different indications in the recipe, it is advisable to let preserves rest for at least half a day before placing them in the pantry. They could in fact absorb oil and therefore it could be necessary to refill them. It is absolutely necessary to consider that, in case oil is topped up, preserves must be pasteurized again…”
Blanch or place raw vegetables that you wish to preserve for the winter, such as capers or olives, etc., in a solution of water and salt (100 g of coarse salt to 1 liter of water). If the salt concentration is lower, the risk of Botulinum may arise.
After that pasteurize the jars as explained above, following the advices of the Ministry of Health.
It is the fruit leather; cooked fruit purea than rolled out finely and dried in the sun to face the long winter months, which don’t offer many varieties.
Preparing it at home is one of the easiest fruit preservation practices there can be, as well as very satisfying.
Wash and stone 1 kg of the fruit of your choice (apricots, plums, apples, grapes, etc.); cook for about 1 hour with 50 ml of water and if you like add 2 tablespoons of natural grape molasses.
Blend the puree, then let it boil again, add if you wish 1-2 handfuls of nuts and spread it thinly on a tray lined with baking paper; expose to the sun: 2-3 days will be more than enough.
Finally, carefully remove the parchment from the baking paper, roll it up and put the “parchment” inside a sealable bag.
As it does not contain any preservative, Pestil should be kept in the refrigerator; however, if you wish, you could increase the quantity of sugar, thus avoiding refrigeration… Frankly, however, I would not see the point, since you have a fridge at home!
It is an excellent way to preserve surplus basil (zucchini or arugula, or nettles, etc.). However, in order not to alter the organoleptic characteristics of the product, home pasteurization is not advisable; therefore the only way to preserve it without the risk of Botulinum is to freeze it. Prepare the portions and keep them in the freezer; thaw only what is necessary to be consumed during the day.
Preserving fresh tomatoes in the ash
I personally haven’t tried this method yet, but I did some research and it seems to work brilliantly.
Sift the ashes from a regular oven/stove or whatever, put in a cardboard box and place the raw, unwashed tomatoes inside (1,2).
The farmer, who received an award for innovation, claims he can preserve the tomatoes in perfect condition for up to 6 months.
Of course, these are just a few of the techniques for preserving fruits and vegetables for the winter; I’m sure many of you know lots more, since you hate wasting food at least as much as I do; so for the common good, share this article and your knowledge with others.
Happy conservation work and good revolution to all
1) Fashanu, Titilope & Akande, Samuel & Lawal, Israel & Ayanda, Ifedapo & Adebayo, Odunayo & Ibrahim, Adeola & Achime, Kennedy & Olasope, Tobi. (2019). Effect of Wood Ash Treatment on Quality Parameters of Matured Green Tomato Fruit (Solanum lycopersicum L.) during Storage. Journal of Experimental Agriculture International. 29. 1-11. 10.9734/JEAI/2019/46042.
2) Effectiveness of wood ash in extending the shelf life of fresh tomatoes http://dissertations.mak.ac.ug/handle/20.500.12281/6349