A lactic starter is a bacterium that produces lactic acid after a process called fermentation.
This fermentation takes place in the absence of oxygen because oxygen is toxic to these bacteria.
To carry out this fermentation, lactic acid bacteria need sugars (lactose, soluble fibre, etc.), which are then converted into lactic acid.
Probiotics are micro-organisms, usually lactic ferments, ingested with food that interact positively with the body.
Not all lactic acid bacteria are probiotics.
In fact, to be effective, probiotics must be able to live in the gut and interact with the gut ecosystem (mucosa, microbiota and immune cells).
To do this, probiotics must meet several criteria:
- Stability: Before ingestion, probiotics are stored in the food or supplement for several weeks or months. Probiotics must be able to stay alive throughout their shelf life. This can be measured by stability studies.
- Gastro-resistant: Like any ingested food, probiotics are subject to stomach acid and degradation by bile salts and digestive juices. Probiotic bacteria can survive the digestive stages. This gastro-resistance can be demonstrated by survival studies.
- Gut interaction: The benefits of probiotics are required to modify the function of the intestinal mucosa and/or the microbiota it harbours. In vitro and in vivo studies are carried out to achieve this.
Probiotic bacteria belong to only a few families (called "genera"), the most important of which have Latin names such as Bifidobacterium, Lactobacillus, Lactococcus and Streptococcus.
Within these large families, research has shown that certain strains have been selected for their ability to survive in the intestine and to develop strong interactions with it.
Among the most studied are:
- Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus, the two species of bacteria responsible for turning milk into yoghurt.
- These two species are the ones that made it possible to discover the existence of bacteria that are beneficial to the body at the beginning of the 20th century.
- Lactobacillus acidophilus
- Lactobacillus rhamnosus subsp. GG
- Lactobacillus helveticus
- Lactobacillus plantarum
- Bifidobacterium animalis subsp. lactis Bifidobacterium infantis
- Bifidobacterium bifidum
Indications
Studies show that adding dairy yeast bacteria to appropriate medical treatment can help reduce the intensity and duration of diarrhoea.
Why is this? Because the intestinal flora, which helps to maintain the balanced functioning of the digestive tract, deteriorates and decreases.
The reduction in the intestinal microbiota thus leaves space in the mucous membranes for pathogenic bacteria, which can maintain or worsen diarrhoea.
The administration of lactic ferments aims to replace these pathogenic bacteria and help restore normal gut flora.
For pain
The bacteria in lactic acid ferment that destroy bacteria that are harmful to the body also help to fight inflammation.
Often asymptomatic in its early stages, inflammation then manifests itself as abdominal pain, bloating and recurrent flatulence.
Lactic ferments help to fight this inflammation.
With the help of lactic ferments, the increased good bacteria will protect the intestinal wall, which will become a real barrier against infections, blocking the entry of new pathogenic germs.
We will then have a strengthened immunity, but also a better control against all kinds of allergens. In fact, research has shown that 70% of the body's immune cells are found in the digestive tract.
Improving nutrition
The gut, restored by the use of lactic ferments that make food more digestible and assimilable, will be able to fully fulfil its nutritional function.
Fermented foods are easier to digest.
Proper digestion results in better absorption of proteins, lipids and carbohydrates, as well as vitamins, minerals and trace elements.
Indirectly, therefore, lactic ferments contribute to a better quality of digestion and nutrition.
Foods
They are naturally present in dairy products (yoghurt and fermented milk), lacto-fermented products (kefir, kombucha, sauerkraut, etc.), soya derivatives, brewer's yeast, etc.
Eating foods rich in fibre, such as wholemeal bread, fruit, vegetables and pulses, promotes the development of a balanced intestinal flora.