How to Make a Fermentation Jar
Did you know that many of the most popular foods and drinks in the world are made through fermentation? Beer, bread, cheese, pickles, sauerkraut, wine and yogurt, among others, are fermented foods. The process of fermentation consists in using bacteria or yeast to turn carbs into organic acids or alcohol. However, this process can only happen under particular conditions. One way you can create the anaerobic conditions to ferment food is by making your own fermentation jars at home.
Stay with us at oneHOWTO and learn how to make a fermentation jar; you'll be able to make your own pickles and other processed foods!
What is a fermentation jar?
Humans started to make fermented food even before they started to write. This process is useful to preserve the food, to make it easier to cook, to make it tastier and also to make it more nutritious.
As you can guess, there are so many different types of fermented foods that there are different methods to prepare them. It is one thing to ferment cabbage in a jar to make crispy kimchi pancakes and quite another to make water kefir or kombucha tea.
However, the general fermentation process is the same for all foods. Sugars and other carbs are transformed into preservative acids (as in pickles), carbon dioxide (as in bread) or alcohol (as in wine or beer) when specific enzymes act on them. These enzymes are secreted by both live and inactive yeast cells.
A fermentation jar is the recipient you will use to keep the food while the process takes place. To ferment food at home, you'll also need other materials such as a food processor or at least a sharp knife, a pounding tool such as a mortar and pestle and different types of lids.
What is the best material for a fermentation jar?
- Glass: This is a comfortable and affordable choice if you're just starting to make your own fermented food. It's chemical-free, it doesn't scratch easily, and it's relatively cheap if you have lots of fermented food to store. You can find canning jars, glass crocks and even mason jars in the market to use as fermentation jars.
- Porcelain: Of course, we're not talking about decorative vases or pottery but food-friendly porcelain. You can technically ferment food in porcelain jars, but they're more expensive and brittle, so they're not the easiest choice to use.
- Ceramic: Ceramic fermentation crocks or jars are not as easy to find, but their large size is useful if you have lots of food to process.
Therefore, the best material for a fermentation jar is glass. Plastic is the least recommended option, because it is often treated with chemicals and is easily scratched.
What is the best lid for a fermentation jar?
Once you have the glass jar in which you'll ferment your food, how are you going to close it? It's very important to prevent oxygen from entering the jar while letting the fermentation gases that appear during the process go away.
In general, whichever lid you choose will be better if it has a water-resistant barrier to prevent unwanted bacteria. You will also need to use a smaller clean jar, a cabbage core or an apple slice as a fermentation weight to ensure that the food you're fermenting stays submerged in the solution.
How to make an airlock lid for a fermentation jar:
In the market you can find many different types of airlock lids and fermentation kits to use with your glass jars. They are your best choice to prevent mold, and you can make your own.
Get a plastic canning jar lid of the wide mouth type and clamp it onto a piece of scrap wood. Drill a very small hole into the plastic: then, use wider drill bits carefully until you get a 1.25 cm (0.5 in) hole. Remember that these lids are thin and may shatter.
You can make your own airlock lid for a glass jar, but if you have never grilled glass before it's better to just take them to a specialized shop and have the hole done there. Even if you have experience drilling glass, it's best to use a drill press instead of a hand-held drill.
Remove any shavings and wash everything. Insert a food-safe rubber grommet into the hole and then insert a rubber gasket. Then, place an airlock fermenter (which you can find in shops) into the hole, until it pokes out of the grommet. Done! You can now put together your homemade airlock jar.
How to make a cloth cover for a fermentation jar:
You can make a homemade lid for your fermentation jar with a clean muslin, dish towel or paper coffee filter. Simply cut them into the desire size and secure the cloth cover with a rubber band. The probability of mold is higher, but it can always be removed. Some people use perforated balloons, but they are not an airtight option and they may have traces of chemicals or foreign bacteria.
How to use a tight lid for a fermentation jar:
You can simply close the glass jar's normal lid very, very tightly. If you go for this easy option, you'll have to "burp" the fermentation jar once every day, which will prevent overflow and excess pressure. Tight lids will prevent mold, but not completely.
Common mistakes when fermenting food
Once you've made your homemade fermentation jar and started to ferment pickles or sauerkraut, you can still have a nasty surprise and discover the food has gone moldy or just doesn't taste right.
- Failure in the anaerobic environment: "anaerobic" means without oxygen. If air enters your fermentation jar, the yeasts may turn into vinegar. If your fermented food has turned pink or brown, if it smells bad or looks slimy, there may be a problem with the airlock.
- Failure in the period of fermentation: microorganisms need to be at room temperature to develop and ferment the food properly. Do not put your jars in the fridge during the fermentation process, which lasts about a month.
If you suspect your fermented food is spoiled or moldy, do not eat it at all. It takes some time for mold to become visible, so if you notice some at the top layers or in the brine solution it may not be enough to remove them: the whole jar could already be spoiled. Here you can read more about what happens if you eat expired food and what to do if you have food poisoning.
This is how to make a fermentation jar, together with how to make lids and airlocks for the jar and what not to do. Don't miss the following related articles!
- How to ferment food for probiotics: fruits and vegetables
- How to pickle cucumbers in vinegar
- How to use leftover pickle juice
- How to make homemade fruit preserves
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