There are many methods of food preservation. The oldest ones go back to prehistoric times, and they included drying, salting and pickling, smoking, burying in the ground and fermentation.
The newer methods include refrigeration, freezing, canning, jelling, or even using sugar.
Just to name a few.
With the onset of technology, harmful chemicals and preservatives are also very often used by big companies to "preserve food". Saving on time and cutting the costs.
I will not go into details about all those different ways, as we want to concentrate on the two methods that are used to preserve vegetables. Namely canning and fermentation.
Especially that those two methods confuse people the most.
Let's take a look at canning first.
"Canning is a method of food preservation in which food is processed and sealed in an airtight container (jars like Mason jars, and steel and tin cans). Canning provides a shelf life that typically ranges from one to five years, although under specific circumstances, it can be much longer."
The above quote is from Wikipedia
The whole idea of canning was developed in France during Napoleonic Wars, specifically in 1809, when Nicolas Apert "observed that food cooked inside a jar did not spoil unless the seals leaked, and developed a method of sealing food in glass jars." (Wikipedia)
So basically almost any food can be preserved this way. Fruits, vegetables, beans, meats, etc.
To find out more about canning, please click here
The pic below, with various canned vegetables, was taken from the linked article.
Two types of containers were and are used for this method. Tins (or cans, hence the term canning) in commercial productions and glass jars or bottles (both at home and commercially).
The canning process of vegetables requires a liquid in which those vegetables are submerged. That liquid (called brine), is usually either a mixture of water + salt, or water + vinegar + salt.
Less common is the use of oil and seasonings. The most common vegetables preserved this way are artichokes, olives or sun dried tomatoes.
The rest of the vegetables are preserved by using the two types of water-based brine.
Most common of them are: cucumbers, red peppers, red cabbage, green peas, corn kernels, beets, okra, anything that has "Pickled" in the name, and also all kinds of vegetables mixes.
Many of those vegetables can be quite tasty, although their nutritional content is usually diminished a bit, as some water-soluble vitamins are lost during the canning process
(that is something that does not happen when the same veggies are fermented).
One of the reasons for that is the fact that "canned" vegetables quite often undergo two heating processes. First they are subjected to a hot brine and next comes the process of sealing.
That requires the jars to be either submerged in a hot water for a certain amount of time or to be placed inside a hot oven till the gets hot enough and the lids seal.
Also, those commercially made canned vegetables may contain the whole plethora of additional preservatives, which diminish even more the value of such foods.
Home canned products will obviously be free from those.
Two of the most confused "canned" versus "fermented" veggies are cucumbers or pickles.
We will compare them in a moment. But first, let's take a look at one of the best way to distinguish between "canned" vs "fermented" categories.
If you find any given vegetable that is sealed inside a glass jar, on a regular store shelf. This vegetable is "canned" and not "fermented".
The reason for that is: "canned" vegetables are shelf stable and they don't require refrigeration.
"Fermented" vegetables, on the other hand, need to be refrigerated as the fermentation process still takes place. They are full of live, probiotic bacteria, vitamins and enzymes, and they keep on fermenting, even inside the glass, retail jars.
The fermentation process is slowed down by lower temperatures, but it is not interrupted.
If those jars were sitting on regular shelves, without refrigeration, the fermentation gases would push the vegetables and the juices out of the jars, and those jars could even explode.
The vast majority of cucumber pickles are vinegar-brine based and they can have names that are exactly the same as salt-brine based fermented cucumber pickles.
Dill pickles or pickled cucumber are just two of them.
So you can't distinguish them by the name. But if you find them inside a refrigerator and the label says "Keep refrigerated" then you almost have the certainty that they are fermented.
If the label says fermented and raw, then you know for sure.
To add to the whole confusion, there's a whole range of vegetables that will have a word "fermented" on the label, but they will sit on a regular shelf and not inside a fridge.
Those will include Cucumber Pickles, Sauerkraut, sometimes Kimchi and other things like Sauerkraut Juice (here in Germany), or even the Brottrunk (which is a fermented grain beverage similar to bread kvass).
Those vegetables might have been fermented at first. Unfortunately, to make them shelf stable (read dead), they were subjected to the process of pasteurization afterwards.
So don't expect to find any of the probiotic bacteria or enzymes inside those products.
The pasteurization is like a sterilization. Nothing that lives survives that process.
Just check the label and you should find the word "pasteurized" right on it.
Here, I also have to mention something specific to Germany.
In BIO (Organic) stores, there are few types of vegetables that one can find sitting on regular shelves (not refrigerated). Those vegetables look exactly like the traditional fermented foods.
Some of them even have a word "fermented" printed on the label and you will not find the word "pasteurized" printed anywhere.
On the other hand, you will not find the magic word "raw" (roh or Rohkost-Qualität), either.
So since this particular word is not there, and since they are not refrigerated, only one conclusion comes to my mind.
That these vegetables do not contain any gut-healthy, probiotic bacteria and enzymes.
Now back to the "fermented and raw" category.
Fermented vegetables require constant refrigeration. That is why you will always find them inside refrigerators, like on this photo from London Fermentary that was taken inside one of the Planet Organic stores in London.
And yes, if you attend a local food market, you can find some Sauerkraut or (fermented) Dill Pickles that will be scooped right out of wood barrels, not refrigerated.
That is how those two were originally prepared. After salting and seasoning, shredded cabbage or cucumbers were stored inside wood barrels in the cellars (in cooler temperatures) so they can be preserved for Winter.
Now, quite often this is only a sales gimmick, and those two are most likely fermented in plastic tubs and later transferred into wood barrels, so they sell better.
Quite often those barrels are lined up with visible plastic bags, to prevent leakage.
That is a good indication that those barrels were not used to ferment the veggies stored inside of them. They are just there for the decoration.
Fermented vegetables should also be clearly marked that they are "fermented" and at the same time that they are still raw (not pasteurized).
Like this one from Hawthorn Valley in the US, with clearly marked: "fermented, probiotic, raw and live"
Just like on our label below.
Companies that produce truly fermented foods make sure that this distinction is clearly marked on their labels.
Unlike "canned" vegetables, fermented vegetables do not lose their nutritional content.
Actually, through the proper fermentation process the nutritional value of the vegetables increases and so does the vitamin contents (vitamins C, K, B vitamins).
Various beneficial organic acids are created, as well as many enzymes.
Fermented foods are also more digestible and a lot easier on the stomach than when they are in their raw state.
Plus, they contain many gut healthy lacto bacteria. And that helps with better digestion and better assimilation of those foods, and it strengthens the immune system. This in consequence ensures better health.
There are some other beneficial processes that happen during the fermentation process.
Here are some passages from BBC GoodFood about them.
"Historically the fermentation technique was used as a way of preserving foods and drinks long before the days of refrigeration. During the process of fermentation, microorganisms such as bacteria, yeast or fungi convert organic compounds – such as sugars and starch – into alcohol or acids. For example, starches and sugars in vegetables and fruits are converted to lactic acid and this lactic acid acts as a natural preservative"....
" The consumption of foods and drinks that have undergone fermentation contain benefits to health that stretch beyond food preservation. The transformation of sugars and starches enhances the natural, beneficial bacteria in food. These bacteria, known as probiotics or ‘good’ bacteria are thought to help a multitude of health issues, specifically digestive health."
For more information about various beneficial bacteria, acids, etc in fermented foods and drinks, please click here
Hopefully this blog helped you a bit with the whole confusion about "canned" and "fermented" vegetables so that you can be more aware which ones to purchase, and which ones maybe to avoid.
Thank you for reading!