Domesticated microbes in use

Why fermented foods are currently making a comeback

Fermentation has been around for a long time and is a kind of original form of biotechnology. It uses microorganisms or their enzymes to make food keep longer and taste better. Today, when consumers choose a food product, health and sustainability are just as important as taste and shelf life. Last but not least, the current search for so-called alternative proteins is helping to reinstate fermentation in the industry. The BRAIN Group has a lot to offer on this topic.

More and more consumers want to eat natural and healthy, preferably also sustainable foods. The trend towards fermented foods is responding to this wish, because fermented foods not only contain health-promoting substances such as certain amino acids or vitamins (see text box below), they can also be sustainable, e.g. if they are plant-based or because they are better preserved. The fermentation of vegetables, for instance, is gaining popularity not only in private households. The industry has also recognized the trend towards fermented foods and is offering more and more varieties.

Cheese thanks to unusual sex

How did the first microorganisms specialize in fermentation? According to a study by University College Cork (UCC), we owe the fermentation product cheese, for example, to the fact that centuries ago humans (initially unconsciously) "domesticated" special yeast fungi along with sheep, goats or cattle. UCC scientists had studied the genome of a yeast cell growing in milk and found that its ancestors lived in fruit flies and were unable to consume lactose. The "modern" lactose-consuming yeast cell must therefore have acquired the necessary genes from another yeast. The scientists suspect a gene transfer in a mating process that is rather unusual for yeasts. So we have sex to thank for our cheeses… as the university says in the headline of its corresponding News and Views item (More about the origin and evolution of the yeast cell Saccharomyces cerevisiae: Duan et al. 2018).

So after our ancestors accidentally came across lactose-consuming microorganisms and were thus able to make fermented, tasty dairy products such as sour milk, yoghurt and cheese, they quickly noticed that this lactic acid fermentation also made the dairy product keep longer. Yet another reason to cultivate or domesticate the valuable microorganisms in the kitchen and cellar! Other fermentation approaches are known to have led to lacto-fermented pickled vegetables such as sauerkraut, or to alcoholic drinks such as fruit wines, mead or beer. Many early fermentation approaches originated in Asian cultures and have long since found their way into our diet e.g. tempeh, miso and tofu, all fermented soy products.

Fermentation experiencing a revival

Despite today's refrigeration options and a wide range of foods, many people appreciate the taste and longer shelf life of fermented foods. But there is another reason why the treatment of food with microorganisms is currently experiencing a revival not only in private households but also in the food industry: fermentation, i.e. the chemical conversion of substances by bacteria or their enzymes, can help to improve the nutritional value and taste of plant-based food raw materials, thus making them more attractive to many consumers as a tasty and sustainable alternative. "Fermentation is the future for the alternative protein industry" was a recent quote from the "Foodnavigator" platform by David Welch, Science and Technology Director at the US non-profit organization Good Food Institute (GFI). The institute promotes the development and production of plant-based alternatives to meat, dairy products, eggs and cultured meat and thus alternatives to products from conventional animal husbandry (foodnavigator.com).

The BRAIN Group provides the food industry with products and solutions for the fermentation and optimization of (alternative and conventional) proteins. This includes starter cultures for fermentation processes and enzymes for the subsequent optimization of proteins.

Starter cultures for the production of fermented food

The diverse and extensive microorganism collection of BRAIN AG ("BioArchive") contains hundreds of strains of microorganisms suitable for fermentation in food quality. Depending on the customer's project, strains are searched for that are suitable, for example, to produce a desired aroma during the fermentation process or to reduce an unhealthy component. The collection continues to be a rich resource for strains that have health-promoting properties for humans, animals or plants, making them predestined for use as probiotics.

If a customer is aiming to obtain a specific ingredient that is produced by a previously selected microorganism strain during the fermentation process, a further process for substance identification and sensory testing of the ingredient follows. The complete chemical and sensory analysis takes place at BRAIN.

If one of the food-grade yeasts or bacteria has proved suitable for the (customer) requirement, the customer can obtain a license to use the strain as a starter culture for a specific field of application. The collection is constantly being expanded, for example to include microorganism cultures known in connection with traditional Asian food preparations.

By combining specialized strains and the state-of-the-art technologies established at BRAIN for the comprehensive microbiological and molecular biological characterization of the strains, we can offer our customers optimal solutions. Due to the synergies within the BRAIN group, these starter cultures can also be produced on a large scale (one-stop shop).

Enzymes for better structure and taste

The structure and taste of (fermented) food can be improved enzymatically. BRAIN group member Biocatalysts has enzymes for this application in its portfolio. In addition to peptidases for the degradation of bitter-tasting peptides, the British company generally also offers enzymes of non-animal origin for protein modification, for example, which enable the manufacture of vegan, kosher or halal products.

Why can fermented food be sustainable?

If you want to do something for your CO2 footprint, one way is to avoid dairy products or reduce their consumption. Alternative products, such as "cheese" made by fermenting cashew nuts or yoghurt made from alternative "dairy products", can be a sustainable alternative to cow's milk products. A prerequisite for consumer acceptance is that they must be formulated into tasty and nutritionally adequate products. If the vegetable basis does not provide many nutrients, additives or upgrading by fermentation are also needed for a physiologically sensible substitute.

If fermentation is used to enhance high-quality by-products from the food industry, this can contribute to the sustainability of a company itself (e.g. bread recycling; Immonen 2020). Example: fermentation can turn side streams from juice production such as skins, kernels and other solids into new valuable products.

Referenzen

• Karlund A et al., Nutrients 2020, Apr; 12(4): 1020. doi: 10.3390/nu12041020
• Gille D et al., Nutrients 2018, 10, 448. DOI: 10.3390/nu10040448
• Immonen M et al., Int J Food Microbiol. 2020 Aug 16;327. doi: 10.1016/j.ijfoodmicro.2020.108652
• Duan S et al.. Nat Commun 2018. Jul 12;9(1):2690. doi: 10.1038/s41467-018-05106-7
• Sivamaruthi BS et al., Nutrients 2018, 10(12): 1973. doi.org/10.3390/nu10121973