Heating canned food in a water bath

Heating canned food in a water bath - pasteurization is a heat treatment of food products at a temperature of 70-90 ° C. It is used for preserving fruits with a relatively delicate pulp and juices from fruits and berries that are not intended for long-term storage. First of all, fruits and berries with a high natural acidity are pasteurized. Also you can find water bath canned recipe online.

For pasteurization, place filled jars or bottles in a saucepan or container with water heated to 50-55 ° C. At the bottom, place a wooden grate or a piece of linen folded in 3-4 layers. The water level should reach almost to the neck of the can, or be slightly lower. Cover the pan with a lid, heat the water to a temperature 1-2 ° C higher than that adopted during pasteurization, keep the set time and, if necessary, heat it. Control the water temperature with a thermometer.

There are several ways to pasteurize. Canned food can be heated in any container with a lid (tank, saucepan, bucket) with a wooden or metal grill on the bottom. The water in the container is heated to 40-70 ° C, the cans are installed, covered with a lid (without sealing), and the required time is maintained at a temperature of 80-90 ° C. The duration of heating depends on the type and condition of the product, the degree of its grinding, acidity and container size, but not less than 30 minutes required for the death of microorganisms.
 

The jars are taken out of the water with special tongs, without opening the lids, put on a towel or clean paper folded in several layers, immediately twisted and rolled on the table several times to make sure they are tight, then cooled, turning over several times. In order to avoid digestion of the fruit when slowly cooling the jars (especially large ones) for 4-6 minutes. immersed in water at a temperature of 65-70 ° C, then for the same time - with a temperature of 35-40 ° C, after which it is left in air. You can use a juicer to sterilize canned food. Banks are installed in it, kept in a steam environment for a certain time, removed with tongs and sealed.
 

After pasteurization, the jars should be placed upside down or put on their side and rolled on the table to better warm the contents. If syrup flows out from under the lid, the seaming must be repeated.

Jars cooled at room temperature are stored in a dark place with a temperature of 0 to 12 ° C.
If jars with glass lids, rubber gaskets and metal clamps are used for canning, they must be sealed before pasteurization and immersed in water so that it covers the jars 3-4 cm higher.

Berry compotes and juices are well stored in milk bottles, covered with two layers of cellophane. To do this, immerse the 10x10 cm cellophane squares in water heated to 70-80 ° C, and alternately, first with one layer, then with another layer, cover the bottles, squeeze them tightly around the neck and tie them with a coarse thread 5-6 turns along the depression and put them on pasteurization.

Sterilization. This is the heat treatment of the product in boiling water, as a result of which microorganisms are completely killed. It is used for the preparation of canned food for long-term storage. The sterilization time of the canned product is calculated from the moment the water boils in the pan, the boil should not be violent.

When using plastic lids for sealing, products should be sterilized (pasteurized) under a used metal lid. At the end of the process, remove the jar from the pan and place on the table. Rinse the polyethylene cover thoroughly, hold it in water heated to 90 ° C using tongs for 1 minute, and then quickly, removing the metal cover, put on the polyethylene cover. Jars sealed with such lids must not be rolled or placed upside down for cooling.
 

At 100 ° C, most microbes die quickly. True, there are very resistant species of bacteria that form so-called spores under unfavorable conditions, which can withstand even prolonged boiling. Once cooled, they may grow new bacteria, although not immediately. But if you heat the food to higher temperatures, for example, up to 115-125 ° C, then you can achieve the complete destruction of all bacteria and their spores, if, of course, the food is kept at such high temperatures for a sufficiently long time. It is on this that food preservation is based on the method of heat sterilization.

The word "sterilization" means supplying, that is, the destruction of living organisms. With regard to canning, this refers to bacteria and other microorganisms, which, once destroyed, can no longer cause spoilage of the product.

But sterilization itself is not a sufficient condition to ensure long-term storage of canned food. Indeed, as soon as the heated product cools down, other microbes from the air will immediately get on it and immediately begin to develop in it, causing damage. To prevent this from happening, during canning, all products are immediately placed in cans, which must be sealed hermetically, that is, so that air cannot enter them. By itself, it is not dangerous, it is important that, along with the air, new microbes do not enter the cans instead of those destroyed during sterilization.

Consequently, the method of preserving food products by sterilization in sealed cans is based on a combination of two main conditions - sealing, i.e. tightly sealing the cans, excluding the penetration of air inside, and sterilization - heating the product together with the can in order to destroy microorganisms inside the container.

Typically, the heating temperature for sterilizing canned food is adjusted to 100 ° C or higher. The heating temperature required to destroy microbes depends on the properties of the products themselves and on the nature of the microflora that causes them to deteriorate. Since the acidic environment is unfavorable for the development of microbes, in products with high acidity the resistance of microorganisms to heat decreases, they seem to weaken, and they can be destroyed by simple boiling. For some products, for example berries, sour marinades (with vinegar), lower sterilization temperatures (below 100 ° C) can be used. Such heating is conventionally called pasteurization, although there is no fundamental difference between these two names.