What are the advantages and disadvantages of furnace canning?

The oven preservation consists of placing glasses filled with hot, freshly prepared high -acid foods such as fruit, jams, jelly or marmalade for a hot oven for heating and sealing. This method has several advantages, the most important is the ability to process a large number of glasses at the same time. It also has a number of disadvantages, including the fact that many food safety experts considered a dangerous canning method.

Unlike stone canning, the preservation of the oven requires no water bath. It requires no careful placement of glasses in boiling water with a pair of pliers and properly listens to the sound of the lid. When it is done correctly, the lids are sealed after they have been screwed into an overheated canning vessel, then heat up for another 15 minutes and cool on the stand or in the oven. Kanner also moves all glasses at the same time because there are a method for highly acidic foods such as apples and pears. Highly acid foods are more resistant tobacteria than foods with low acid content such as vegetables or meat. Low acid foods require longer heating at a higher temperature for proper maintenance, so that the oven preservation is not recommended for them.

furnaces emit dry heat instead of steam, so the glasses are slowly warm and during the heating process could break. The dry heat of the oven can also endanger the rubber seal of the canned lid lid if the container is left in the oven for too long. When sealing properly, the lid creates a vacuum that keeps air and bacteria outside the container. Dry heat also changes the food temperature more slowly than steam or water bath, giving bacteria more time to achieve food, especially if the temperature does not reach 212 degrees Fahrenheit (100 degrees Celsius).

This method also does not guarantee that the food is preserved to a constant mpnance temperature required for killing bacteria. Most instructionsThe oven preservation includes heating the canning container without lids, at least for the second part of the process. Once the Canner removes containers without the people from the oven to install the lids, food, container and the surrounding area, it will cool down, increasing the risk of dirty content. The furnaces may also differ from what the button or digital thermostat reads, so the oven does not have to be heated to the desired temperature. The temperature inside the oven may also vary depending on where the glasses are located - for example, the center, sides or the upper part - so the glass does not have to reach uniform temperatures.

Oven preservation method is also highly sensitive to user error. The container content can be bubble and spilled, even if the canned follows the required 0.25-0.5 inches (about 0.6-1.3 cm) in each container. When removing the glass vessel from O, also when removing the glass container, it also risks burns or broken enamel.