In order to answer this correctly, it is helpful to understand the whole concept of lacto- fermentation.
So what exactly is lacto-fermentation?
Lacto-fermentation is a food preservation process that produces such foods like Sauerkraut, Dill Pickles, Kimchi, etc.
To put it simply, it's a transformation process during which good bacteria, which are already present on vegetables, thrive in a salty and anaerobic (meaning oxygen free) environment.
The "not so good bacteria", which can not survive the same environment, die off, making those foods safe to eat.
Those salt tolerant bacteria belong to the group called Lactobacillus and there are many species that belong to this genus.
This salty environment refers obviously to vegetable fermentation, as milk fermentation undergoes a slightly different scenario.
During this transformation process, Lactobacillus bacteria convert sugars that are naturally present in vegetables (or fruits, or even milk products) into lactic acid.
At that time the carbon dioxide is also produced, which then pushes out the existing oxygen. This makes the food more acidic and it encourages the creation of even more Lactobacillus bacteria.
Lactobacillus bacteria were first discovered and studied in milk products, since they were the ones responsible for breaking down milk's sugars known as lactose.
The lactic acid is a natural preservative and it helps fight those "not so good bacteria".
It also preserves the already existing nutrients.
This whole fermentation process contributes to the increase of the available vitamins (especially vitamin C) and it also creates additional vitamins (like those belonging to B group), as well as beneficial enzymes. It also gives the vegetables a distinct sour flavor (hence Sauer + Kraut = sour cabbage).
Lacto-fermentation also makes those fermented foods more bioavailable.
Meaning your digestive system does not have to do so much work to break them down, as they are already broken down by the Lactobacillus bacteria (think of them as "pre-chewed") and it can absorb more easily the available nutrients.
When the vegetables are properly fermented, they also have some other benefits, besides their bioavailability. Some of those benefits include the increased immune function, as fermented foods add beneficial bacteria to our digestive track. And since about 80% of our immune system is located in our gut, those bacteria help maintain the balance we need for the healthy immune system.
Better digestion also decreases the problems of having constipation, or even diarrhea.
Eating fermented foods usually increases your energy levels, because the bacteria in your gut are allowing more vitamins and minerals to be absorbed, and used by your body.
Consequently this allows you to eat less and be more satisfied with what you eat.
Fermented foods can reduce problems like brain fog, anxiety, moodiness, or depression and you end up having less food swings and cravings (like craving sweets or something salty).
They also help with faster recovery from yeast infections and they are believed to have anti-inflammatory properties.
There are few more benefits that stem from lacto-fermentation or fermentation in general, some of them are listed in the article by BBC Good Food that can be found by clicking here or the ones listed by Cleveland Clinic, which can be found here
So when you understand the whole fermentation process, you should also understand how crucial it is for those fermented foods to reach their ultimate potential. And this potential can only be reached when those foods are fully fermented and broken down by bacteria, allowing the creation of all beneficial substances, like the lactic acid, enzymes, vitamins, etc.
For that reason we ferment all of our vegetables for a minimum of one month and this is exactly what we teach through our workshops, our brochures, our Facebook group and our social media posts.
And yes, the fermentation time could vary, depending on the foods that you ferment. For example if you want to ferment ripe avocados, it is kind of obvious that you do not need a month to do that. The same goes for other more digestible foods like tomatoes or even cucumbers.
Cabbages, onions, cauliflower, beets, etc require a lot longer time to be fully fermented.
Sure, you could eat those vegetables raw, but many people will have problems properly digesting them. That usually leads to problems like bloating. The same happens to not fully fermented foods. A lot of people get bloating by eating Sauerkraut or those types of ferments that were only fermented for a week or two.
Unfortunately fermenting vegetables for a week or two, is a wide spread trend, propagated not only by a lot of home fermentation "experts" but also by many commercial producers.
If you follow this trend, you will end up not only with a inferior product (a one that has not reached its full potential) but also with a one that will most likely give you some gastrointestinal problems.
All you have to do is to look how those foods were prepared historically. Most of them, especially various forms of Sauerkraut, were made in Fall (Autumn) and were consumed during long Winter months, when not much else was available.
And this preservation process (fermentation) was done out of necessity to preserve the precious fruits of labor that were harvested from the fields.
Now all that, brings us to another point that we always stress and recommend.
When you ferment your vegetables at home, it is not that economical to make them in small glass jars (like the ones offered in so many Fermentation Sets).
You have to wait a month or so for them to be ready and then you only have couple of small jars.
Don't worry about ending up with having too much of those delicious fermented veggies.
When they are done, you can transfer them into smaller jars and place them inside the refrigerator.
There, they can sit for at least up to one year, or even longer. During that time they will continue fermenting, but at the much slower rate, and quite often they will get even more tasty.
So let your veggies reach a full potential and let them ferment for at least one month!