Preserve your raw vegetables for months with this lacto-fermentation technique.
This tutorial has been created in collaboration with Claire Yobé, a lacto-fermentation instructor with over thirty years of experience in this field.
The aim is to easily preserve surplus vegetables for long-term storage, whether from your vegetable patch (in Summer for example), or because you have bought more vegetables than you needed.
Key facts on food wastage:
What is lacto-fermentation, or lactic acid fermentation?
Lacto-fermentation is the conversion of sugars into lactic acid by lactic acid bacteria (naturally present specific microorganisms).
This method of fermentation has been used for centuries to preserve milk (e.g yoghurt), vegetables (e.g saurkraut), meat (e.g. cured sausage) and even fish (e.g fish sauce).
How is it possible to preserve vegetables by means of lactic acid fermentation?
Vegetables carry microorganisms on their surfaces (microscopic fungi, bacteria) which, when left in the open air, cause them to rot. The absence of air (anaerobic conditions) and a small quantity of salt to inhibit other bacteria, encourages the lactic acid bacteria to grow: this is the start of the lacto-fermentation process.
These bacteria grow by feeding off the sugars present in the food, and converting them into lactic acid. The amount of lactic acid gradually increases and the brine becomes more and more acidic.
This acidity neutralises the rotting process. When the environment is acidic enough (approx. pH 4), the lactic acid bacteria are also inhibited. The product becomes stable, which allows for long term storage of up to several months and sometimes even years.
What kind of vegetables can be preserved with lacto-fermentation?
Nearly all vegetables which are eaten raw can be preserved this way. (E.g cabbage, cucumber, carrots, beetroot, etc...)
What are the nutritional and health benefits of lacto-fermented vegetables?
1) They aid digestion and nutrient absorption.
Enzymes in lactic acid bacteria "pre-digest" vegtables, which helps the digestion process as well as the absorption of nutrients and minerals by the body.
2) They are a source of vitamins.
Lacto-fermented vegetables have the same amount of vitamins, and sometimes more, as raw vegetables.
3) They help the intestines and immune system function properly.
Lactic acid bacteria are "pro-biotics" for the gut flora which play an important role as barriers for the immune system.
How can we consume lacto-fermented vegetables?
Lacto-fermented vegetables can be consumed frequently, on a daily basis even, for example as a side dish.
Eating a lot in one go can cause stomach pains due to its elevated acidity levels.
They should be part of a varied and balanced diet.
Y a t-il des risques avec la lactofermentation?
Contrairement à la conservation par traitement à la chaleur (ex: stérilisation) ou à la congélation, qui peuvent présenter de grands risques en cas de problèmes (mauvaises fermetures, décongélation involontaire) et provoquer par exemple le développement de la toxine botulique, la lactofermentation est un procédé très sûr.
Le milieu acide permet notamment d'éviter le développement de pathogène.Cependant, en cas de doutes, de mauvaises odeurs ou de couleurs inappropriées, ne pas hésiter à jeter la conserve.
Remarque: Tasser permet de faire pénétrer le sel dans le légume afin de favoriser l'extraction de jus et de chasser le maximum d'air