Beneficial Microbes in Food Preservation

The Unseen Heroes: Beneficial Microbes in Food Preservation

Not all microbes are dangerous.

We often associate microbes with diseases and infections. It’s important to note that “not all microbes are harmful”. In fact, there are so many beneficial microbes that play an essential role in various aspects of our lives that, includes food preservation. These unseen heroes are responsible for the fermentation and preservation of food, contributing to flavor enhancement, improved shelf life, and even improved nutritional value. It’s simple to say that “the microbes rule the world!”[1].

What are beneficial microbes, and how do they contribute to food preservation?

Beneficial microbes is also known as probiotics or fermentation agents. They provide health benefits when consumed [2] and play a vital role in food preservation. Lactic acid bacteria (LAB), acetic acid bacteria, yeasts, probiotics, and bacteriocin-producing bacteria are beneficial microbes that play a role in food preservation [3]. These organisms produce organic acids, alcohol, and other compounds that disrupt the growth of harmful bacteria through fermentation by converting sugars and other components in food. The texture and taste of foods are altered during the fermentation process, this makes them more tasty and also extends their shelf life.

Fermented foods: The result of microbial magic

Through the process of fermentation, beneficial microbes transform raw ingredients into unique and flavorful products [4], these products are called Fermented foods. Over the years, many foods undergo fermentation, such as meat and fish, dairy, vegetables, soybeans, other legumes, cereals and fruits.  Cultured milk, yoghurt, wine, beer, cider, kimchi and sauerkraut are some examples of fermented foods. Carbohydrates can be converted to lactic acid in the presence of  lactic acid bacteria like Lactobacillus and Streptococcus in food, which creates an acidic environment that inhibits the growth of spoilage bacteria [5] while acetic acid bacteria are responsible for the production of acetic acid in vinegar [6].

Beneficial microbes in flavor development

Beneficial microbes like LAB contribute significantly to the development of complex and distinct flavors in fermented foods [7]. For example, specific strains of LAB are responsible for the characteristic sweet and tangy flavor of yogurt [8] and the fruity flavors in many kinds of cheese [9].  Various aromatic compounds produced by yeasts, including organic acids, esters, and alcohols, enhance foods’ taste and aroma during fermentation [10]. For example, Saccharomyces cerevisiae,  a yeast used in bread making, plays a crucial role by producing carbon dioxide, which helps the dough rise and contributes to the aroma and flavor profile of the bread.

Extended shelf life through microbial action

By inhibiting the growth of spoilage microorganisms, beneficial microbes help extend the shelf life of fermented foods. Microorganisms like LAB, acetic acid bacteria and other probiotics produce antimicrobial compounds, such as bacteriocins,  which kill or inhibit the growth of bacteria [11]. These compounds prevent spoilage and protect the food from pathogens. The acidic environment LAB creates in fermented vegetables and fruits also inhibits the growth of pathogens, ensuring their preservation.

Enhanced nutritional value of fermented foods

The Inclusion of fermented food and beverages in our daily food intake can deliver improved nutrition across the course of one’s life [12]. Beneficial microbes increase the bioavailability of nutrients like vitamins, minerals, and amino acids that are easily absorbed by the body, this enhances the nutritional value of fermented foods.  Dairy products like yogurt and kefir which have been fermented, contain probiotics that can improve gut health and help in digestion. This contributes to a healthy gut microbiota, which is vital for overall well-being.

A fascinating group of beneficial microbes contributes significantly to preserving and enhancing various food products. Understanding the roles of these beneficial microbes allows us to appreciate their impact on food preservation. Below they are presented some of these beneficial microbes and their specific roles in food preservation:

Lactic Acid Bacteria

Lactic acid bacteria, such as Lactobacillus and Streptococcus, convert carbohydrates into lactic acid during fermentation. This process creates an acidic environment that inhibits the growth of spoilage bacteria, thus extending the shelf life of fermented foods. Additionally, specific strains of lactic acid bacteria contribute to the characteristic flavors of products like yogurt and certain cheeses.

Acetic Acid Bacteria

Acetic acid bacteria are responsible for the production of acetic acid, a vital component in the creation of vinegar. The presence of acetic acid inhibits the growth of harmful bacteria, ensuring the preservation of foods like pickles and pickled vegetables.

Yeasts

Yeasts are essential for fermentation processes, producing carbon dioxide, which aids in dough rising and contributes to the texture and flavor of various baked goods. In fermented beverages like beer and wine, yeasts play a central role in converting sugars into alcohol, transforming raw ingredients into enjoyable beverages.

Probiotics

Probiotics, known for their health benefits when consumed, also play a significant role in food preservation. These beneficial microorganisms contribute to the extended shelf life of fermented foods and beverages. Additionally, they enhance the nutritional value of products like yogurt and kefir, promoting gut health and aiding in digestion.

Bacteriocin-producing bacteria

Certain beneficial bacteria produce antimicrobial compounds known as bacteriocins. These natural preservatives inhibit the growth of harmful bacteria and safeguard foods from spoilage and contamination. Bacteriocin-producing bacteria are used in various food preservation techniques to improve food safety and prolong product shelf life.

The future of beneficial microbes in food preservation

The future of beneficial microbes in food preservation holds great promise. As we continue to deepen our understanding of their role, researchers, food manufacturers, and scientists are exploring innovative ways to utilize the power of these microbes to improve food safety, reduce waste, and extend the shelf life of various food products. This includes the development of functional foods, which offer specific health benefits beyond basic nutrition. As consumers become increasingly aware of the importance of a healthy gut microbiome, specific strains of probiotics in food products are gaining popularity.

Conclusion

The world of food preservation owes much to the unsung heroes – the beneficial microbes. Their remarkable ability to transform raw ingredients into flavorful, nutritious, and safe foods is nothing short of extraordinary. Fermented foods stand as a testament to the wonders that these microbes create. By extending shelf life, enhancing flavors, and increasing nutritional value, they have enriched our culinary landscape in countless ways.

As we gain a deeper understanding of the glorious secrets of beneficial microbes, we can expect to see their influence grow, leading to even more exciting and innovative developments in food preservation. So, the next time you enjoy a delicious piece of cheese or a tangy bite of sauerkraut, remember the unseen heroes at work, preserving and enhancing the food we love.

References

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