<i>“</i><i>The processes required for fermented foods were present on earth when man appeared on the scene</i><i>…</i><i>When we study these foods, we are in fact studying the most intimate relationships between man, microbe and foods.</i><i>”</i><i> </i>
<b>Prof. Keith H. Steinkraus</b>

Fermentation is one of the oldest forms of food preservation, having been used for thousands of years. Fermentation is a natural process and our ancestors recognised the favourable taste, preservation and nutritional qualities of fermented foods such as vegetables, bread, cheese and wine without fully understanding the science behind it.

Fast forward thousands of years to a time where people no longer need these traditional methods of storing their food due to modern advances such as the fridge and year round availability of foods. However, despite such advances there has been a renewed interest in these foods, and for very good reason.

Essentially the fermentation process is the slow decomposition of food by microorganisms, enzymes or a combination of both. The 3 major microorganisms involved in the fermentation process include bacteria, yeasts and moulds. These microorganisms are found abundantly in nature and in foods. Whilst some strains have the potential to cause food spoilage or poisoning, with fermentation, it is the presence and growth of beneficial microorganisms that produce desirable "spoilage" effects. The carbohydrates in the fermentation process serve as food for microorganisms which break them down, producing by-products of carbon dioxide, alcohol, acids and hydrogen all of which give fermented foods their distinctive flavour and aroma. As they consume the carbohydrates and contribute by-products, the subsequent changes in the environment of the food suppresses the growth of unfavourable micro-organisms and provide the food with their characteristic flavours and texture. There are 6 main factors that influence the growth and activity of microbes in food: oxygen concentration, moisture, temperature, ph level, nutrients and inhibitors. By manipulating of any of these 6 factors we can control the growth and activity of the desirable microbes involved in fermentation.

Sauerkraut, traditionally made in Germany is a great example of a common fermented food which is the acidic fermentation of cabbage by lactic acid producing bacteria. Sauerkraut literally translates into “Acid Cabbage”. Shredded cabbage and pure salt are placed in a jar under mechanical pressure. The salt and pressure withdraws moisture from the cabbage to create a favourable environment for the bacteria to grow. Different strains of bacteria will grow and produce lactic acid until the acidity reaches about 2-2.5%. The end product is a mix of lactic acid, acetic acid, carbon dioxide and aromatic compounds which create the characteristic flavour. The acid environment prevents unfavourable microorganisms from growing therefore extending the shelf life.

From a health perspective there is growing interest into fermented foods as evidence shows a possible connection between how the microbes act in food pre-consumption, and in turn the ways in which the microbes in these foods influence our body’s microbiota. It has been reported that fermented foods can provide us with a dietary source of beneficial gut microbes however more evidence is needed on this topic as it is not properly understood if they able to survive the harsh environment of the human stomach. Fermented foods have been found to magnify protein quality and bioavailability of Vitamin B, magnesium and zinc, all of which is very positive from a nutrition perspective.

Unfortunately there are millions of people around the world who still do not have enough food today. Food and Agriculture Organisation of the United nations (FAO) are working with other major organisations to tackle food security which is still a big problem for developing countries. There is real potential for fermentation to play an important role in developing countries. Being a relatively efficient preservation process, increasing product shelf life and decreases the need for refrigeration and other more expensive preservation techniques and equally as important is its

Therefore, in addition to fermentation being a very important process in food production there is now growing evidence that fermented foods have many health benefits. So get out there and explore some of these fantastic and ancient foods, maybe even try making your own!

Alex