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. Fermentation can produce quite distinctive, strong, slightly sour flavours.
Fermented foods are rich in probiotic bacteria so by consuming fermented foods you are adding beneficial bacteria and enzymes to your overall intestinal flora, increasing the health of your gut microbiome and digestive system and enhancing the immune system.
Digestion and absorption
As some of the sugars and starches in food have been broken down through the process, fermented foods are easier to digest. For example, fermentation breaks down the lactose in milk to simpler sugars – glucose and galactose – which, if you are lactose intolerant, can make products such as yogurt and cheese potentially easier to digest.
Synthesis and availability of nutrients
Fermentation can also increase the availability of vitamins and minerals for our bodies to absorb. Additionally, by boosting the beneficial bacteria in your gut, you are promoting their ability to manufacture B vitamins and synthesise vitamin K.
A large proportion of the immune system is housed in the gut. By consuming probiotic-rich foods, you are supporting the mucosa (gut lining) as a natural barrier, making the immune system more robust. A lack of beneficial bacteria allows disease causing microbes to grow causing inflammation in the gut wall. If you have recently taken a course of antibiotics, probiotic foods are particularly helpful.
Some natural compounds that interfere with the absorption of nutrients can be removed by fermentation. Phytic acid, for example, which is found in legumes and seeds, binds minerals such as iron and zinc, reducing their absorption when eaten. However, phytic acid can be broken down during fermentation so the minerals become available.
Mood and behaviour
The gut and brain are linked, through the hypothalamic-pituitary-adrenal (HPA) axis. Technically called the enteric nervous system, the gut is lined with neurons that can influence our emotions and feelings. Serotonin – a neurotransmitter involved in mood – is made in the gut and research further suggests that as probiotic bacteria contribute to a healthy gut, they are also linked to a healthy mind.
Fermentation not only gives fermented products a unique sensory signature but can also enhance the nutritional value and digestibility of foods in several ways. The process of fermentation can produce vitamins, anti-oxidants, and molecules that lower blood pressure and inflammation. Beyond nutritional value, fermented foods which contain live bacteria may influence the intestinal microbiota. Although the live microorganisms found in fermented food tend to pass through the gut transiently, if consumed regularly, they may be able to influence the gut microbiota by out-competing undesirable microbes. We are all recommended to make wise use of fermented foods from our store houses,always good for our body.