You surely know that different types of fermentation are used to make great foods like beer and cheese, but did you know that it's also used to make soy sauce, pepperoni, sauerkraut, yogurt, bread, and even chocolate? Food has been fermented by humans since the Neolithic era, long before anybody understood the science underlying fermentation. We now understand why fermentation not only improves the flavor of foods like sourdough bread, cheese, and wine, but also serves to keep us alive, thanks to the scientific findings of French scientist Louis Pasteur, who demonstrated that living organisms begin fermentation. So, what are the 3 types of fermentation? Today we are bringing you some great information about the three types of fermentation and fermented foods, lactic acid fermentation, ethanol or alcohol fermentation and acetic acid fermentation. Learn a little about the science behind each ferment and how they lend themselves to some yummy fermented recipes!
WHAT IS FERMENTATION?Fermentation is the chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat. Fermentation is any metabolic process in which the action of microbes causes a desired change in food or drinks, whether it's to improve flavor, preserve goods, or provide health benefits. Ferment is derived from the Latin verb "fervere," which means "to boil." Fermentation is, ironically, achievable without the use of heat.
WHAT DOES FERMENTATION DO TO OUR FOOD?Fermentation takes place in the absence of oxygen (anaerobic conditions) and in the presence of beneficial microorganisms that get their energy from fermentation (yeasts, molds, and bacteria). Even when oxygen is plentiful, some yeast cells, such as Saccharomyces cerevisiae, prefer fermentation to aerobic respiration if there is enough sugar available. These beneficial microorganisms break down sugars and starches into alcohols and acids during the fermentation process, making food more nutritious and preserving it so it may be stored for extended periods of time without rotting. The enzymes required for digestion are found in fermentation products. This is significant because individuals are born with a certain amount of enzymes, which decreases as they become older. Fermented foods have the enzymes needed to digest them. Pre-digestion is also aided by fermentation. Microbes feed on sugars and starches during the fermentation process, breaking down food before it is digested. We love this TedED talk by Erez Garty. It really breaks down the process and gives some great insight into fermentation. Take a look at this video by TedED.
THE 3 TYPES OF FERMENTATION
1. Lactic Acid Fermentation (Or Lacto- Fermentation)
Lacto-Fermentation is arguably one of the most common types found in food. Lactic acid fermentation is responsible for the production of foods like yogurt, sauerkraut, and pickles. Thanks to lactic acid bacteria, a sequence of chemical processes change your components into something quite different (and delicious).
No heat is required in the conversion of starches or sugars to lactic acid by yeast strains and bacteria. Pyruvic acid employs nicotinamide adenine dinucleotide + hydrogen (NADH) to create lactic acid and NAD+ in these anaerobic chemical processes. (Fun Fact: Lactic acid fermentation takes place in human muscle cells as well.) Many of the tasty ferments that you may already be acquainted with may be made using this approach. Lactic acid bacteria aid in the preservation of foods. Look at it this way: yogurt and sour cream are both preserved forms of milk, while sauerkraut is a preserved cabbage. They also induce desirable changes in flavor and texture in addition to preservation! Want to read more about lacto-fermentation? We go into detail in another blog post: What is Laco-Fermentation?
2. Ethanol Fermentation And Alcohol FermentationBrewing beer and manufacturing wine have become hugely profitable agricultural enterprises. These industries sprang from ancient and empirical knowledge gathered from a variety of cultures throughout the world. This historical expertise has now been coupled with fundamental scientific understanding and applied to current manufacturing techniques.
- In the first step, glucose is converted to pyruvate by glycolysis
- In the second step, pyruvate is converted to ethanol and carbon dioxide by using a molecule of NADH
3. Acetic Acid FermentationGrain and fruit starches and sugars ferment to produce sour vinegar and sauces. Apple cider vinegar, wine vinegar, and kombucha are examples of products that utilize this form of
Vinegar is produced when acetic acid bacteria act on alcoholic beverages such as wine. They are used to perform specific oxidation reactions through processes called “oxidative fermentation”, which creates vinegar as a byproduct.
TYPES OF FERMENTED FOODS
Kefir is a consumable yogurt-like fermented milk product prepared from cow, goat, or sheep's milk. Vitamin B12, calcium, magnesium, vitamin K2, biotin, folate, enzymes, and probiotics are all found in significant amounts in kefir.
Kefir has been ingested in some form or another for over 3,000 years. The name "kefir" was coined in Russia and Turkey to describe a drink that makes you feel wonderful. Best of all, Cultures For Health has starter grains that make it easy to get started at home!
2. KombuchaKombucha is a black tea and sugar fermented beverage (from various sources like cane sugar, fruit or honey). When coupled with sugar, it includes a colony of bacteria and yeast that kicks off the fermentation process.
3. SauerkrautSauerkraut is one of the oldest traditional meals, with 2,000-year-old or more origins in German, Russian, and Chinese cuisine. Although the Germans were not the first to manufacture sauerkraut, the word sauerkraut literally means "sour cabbage."
4. PicklesDidn't realize pickles had probiotics? Fermented pickles are high in vitamins and minerals, as well as antioxidants and probiotic bacteria that are good for your gut. Is it true that store-bought pickles are fermented? Normally, no. Most store-bought pickles are produced using vinegar and cucumbers, which, although giving them a sour taste, does not result in natural fermentation. Cucumbers and brine (salt + water) should be used to make fermented pickles.
5. TempehTempeh, a foodstuff prepared by mixing soybeans with a tempeh starter, is another nutritious fermented food manufactured using soybeans (which is a mix of live mold). After a day or two, it transforms into a solid, cake-like product that contains both probiotics and a substantial amount of protein. Tempeh resembles tofu, but it is less spongy and more "grainy."
6. KimchiKimchi is a classic Korean fermented meal prepared with vegetables such as cabbage and spices such as ginger, garlic, pepper, and other seasonings. It's frequently used in Korean dishes such as rice bowls, ramen, and bibimbap. It goes back to the seventh century and is considered a Korean delicacy.
7. Apple Cider VinegarRaw apple cider vinegar with "the mother" has been fermented and includes some probiotics. It also contains specific acids, such as acetic acid, which help probiotics and prebiotics operate properly in your stomach. Most store vinegars, on the other hand, are devoid of probiotics. Twice a day, add one tablespoon of apple cider vinegar to a drink. To significantly raise probiotic levels, add one tablespoon of apple cider vinegar to your diet before breakfast, lunch, or dinner, and then start eating more fermented veggies like sauerkraut and kimchi or drinking kvass.
8. Sourdough BreadSourdough is a naturally leavened bread that rises without the aid of commercial yeast. Instead, it rises with the help of a sourdough starter culture, which is a fermented flour and water mixture containing wild yeast and beneficial bacteria. This is also how sourdough gets its acidic flavor and slightly chewy texture. Wild yeast has a stronger flavor than commercial yeast and is all-natural, as it contains no additives.
9. Cottage CheeseFood makers are beginning to make probiotic dairy products such as cottage cheese more widely available as more research confirms the benefits of probiotics. Cottage cheese, like yogurt, may be fermented when bacteria aid in the breakdown of lactose (a form of sugar) in the dairy. Look for cottage cheese that is low in sugar and has active cultures while shopping. Some varieties are also known as farmer's cheese or dry curd cottage cheese.
10. Coconut Kefir
Coconut kefir is a fantastic option for individuals who can't have dairy. This probiotic-rich drink is prepared with creamy coconut milk and kefir grains, but it's dairy-free and vegan-friendly, unlike conventional kefir or yogurt. You may use it in smoothies, baked products, with fruit, on its own, and so on. Simply choose products that are low in sugar or unflavored, and flavor with stevia, fruit, or honey if desired.