Fermented Foods: Production and Food Safety
Fermented food and beverages can be viewed as one of the safer choices in food, thanks to the production of lactic acid, which does not allow for the survival of most pathogens due to the acidic environment inherent to these products. However, critical errors in processing for fermented food can also pose a risk to food safety.
Although fermentation is an ancient science, fermented food and beverages have gained immense popularity in recent years. Now more people are beginning to understand the benefits of a healthy gut microbiome. As a result, activities like drinking apple cider vinegar and taking probiotic supplements to get a daily dose of healthy bacteria have become all the rage.
Sales of fermented products like wine, beer, cheeses, meats, yogurts, kefir, vegetables, and kombucha increased to a whopping 149% in just 2018 alone with continued annual growth. As more companies look at opportunities in fermented food production, understanding fermentation is essential.
Key Facts about Fermentation Chemistry
Fermentation is a biochemical reaction that extracts energy from carbohydrates or sugars anaerobically. As such, it uses microbes to break down the sugars into alcohol, acid, and volatile compounds. This way, fermenting microbes produce adenosine triphosphate (ATP) to stay alive. But in the process, they also produce other byproducts like ethanol, carbon dioxide, and lactic acid. These compounds increase the products' shelf lives and are part of the desirable sensory qualities of fermented food products.
This chemical process is used in the biotechnology industry for food production, pharmaceutical production, food additives, and animal feedstuffs. Fermentation produces many organic components such as ethanol, butanol, isopropanol, acetone, 2-3 butanediol, glycol, and acetic acid. As the concentrations of these alcohols increase, the fermentation process starts to slow down eventually resulting in the termination of fermentation (Scott, 1995). Separation of these byproducts is used in food production and industrial purposes.
The Role of Microbiology in Fermentation
A variety of microorganisms are used in the process of making fermented food and beverages. For instance, Saccharomyces cerevisiae (baker's yeast) is used to metabolize sugars into pyruvate in beer or wine production. In other fermented foods like sauerkraut, lactic acid bacteria (LAB) are "fed" with glucose and fructose to produce sugars, citric acid, malic acid, acetic acid, and lactic acid, that contribute to the unique flavor and aroma of the food (Satora et al., 2021). Salami, on the other hand undergoes a fermentation process with strains from lactobacillus and/or staphylococcus groups. Lactiplantibacillus plantarum and Saccharomyces cerevisiae are also used to improve the flavor of cured duck leg meat. The microbial fermentation process increases the level of volatile flavor compounds as well as produces the amino acid, glutamate, thereby improving the umami taste of the duck meat.
Potential Benefits
Fermentation attracted scientific interest over the past years due to the potential benefits of fermented food. However, establishing their health benefits can be difficult due to the lack of standardization in vivo. Further, the type and concentration of microorganisms used in fermented foods are not standardized. These variations make the health benefits of fermented food hard to confirm, but still a budding area of research to learn more.
Research suggests some microorganisms used in the fermentation process may be associated with health benefits. For instance, lactic acid bacteria (LAB) can aid in the synthesis of vitamins and minerals. Some LAB species also produce peptides like conjugated linoleic acids that have a blood pressure-lowering effect, exopolysaccharides that have prebiotic properties, and bacteriocins that fight off pathogenic microbes in the gut (Sanlier et al., 2019).
Considerations for the Production of Fermented Foods
For fermented food to remain safe and palatable, salt level, proper fermentation temperature, and sufficient acid production should be considered. There should be just enough food substrates for the fermenters. Otherwise, there might be an invasion of spoilage or food poisoning microorganisms that will compromise the safety of your fermented foods.
Fermented food with lactic acid is considered generally safe. Further, fermented foods produced with good manufacturing processes and have the appropriate acid, salt, and sugar content keep pathogenic microorganisms at bay.
The Importance of Testing Fermented Food Products
Despite the certain sensory and sustainability advantages of fermented foods, certain cases of microbial foodborne infection have been associated with fermented foods like cheese, sausages, fermented fish, and fermented cereals (Nout, 1994). This underscores the importance of professional testing to safeguard against foodborne illness and protect consumer health. These and other products like kombuchas, kefirs, and other probiotic and fermented beverages require special attention as these types of matrices contain complex microbiological environments requiring special testing methods.
Make sure that you're observing the safety and quality standards in your fermented food products. Partnering with a reputable laboratory is critical to ensure safety and quality in your fermented food products. Eurofins Microbiology Laboratories, Inc. – Madison, WI is proud to be a leading ISO 17025 accredited testing laboratory for probiotic testing, partnering with many probiotic suppliers to run strain-specific enumeration procedures.
Reach out to us to learn more on how we can partner with your team!
