Introduction to fermentation

28. June 2022.

„Fermentation may have been a better invention than fire“ – David Wallance

Black, green tea, scoby, bread, baker’s and champagne yeast, sugar, health…
Terms that seemingly have nothing in common, but together make two similar, yet different drinks:
We will introduce you to the world of fermentation in our own way, share with you the history and present and our ways of preparing these two nowadays increasingly popular drinks.
But let’s start in the right order.
How else than with some key terms so that you can follow the rest of the text without any questions and so you can always return to them.

SCOBYasymbiotic bacteria and yeast culture; also known as pelicula, mother scoby, culture, fungus (although technically not a fungus), used during fermentation to inoculate sweet tea with bacteria and yeast to produce kombucha
BABY SCOBY: new SCOBY formed during the first fermentation; may take on the form of a liquid surface; new layer that binds to the original SCOBY
During the second fermentation, baby SCOBIES look like clumps of yeast or sediment in a bottle.
SCOBY HOTEL: SCOBY storage tank
TEA: beverage made from soaked and processed leaves and buds of camellia sinensis. Main tea varieties: white, green, yellow, oolong, black, pu-erh.
pH: measure of acidity or alkalinity on a scale from 0 to 14. The finished kombucha has a pH of approximately 2.5 to 3.5.
YEAST: a single-celled fungus that cannot be seen with the naked eye that belongs to the microorganisms group
There are several types of yeast and the scientific name of the most famous yeast strain is saccharomyces cerevisiae. This strain is very strong and capable of fermentation, it’s most commonly referred to as brewer’s yeast and baker’s yeast.

What is fermentation?
Fermentation has been around for as long as we have and humans used yeast before they learned how to write.
The term “ferment” comes from the Latin word fervere, which literally means “to cook”.
So with this in mind, we define fermentation as a process in which yeast “eats” sugar without the presence of oxygen and releases CO2 and alcohol (ethanol).
Fermentation enables us to explore flavors we cannot obtain commercially and it can change our thinking and perception of some flavors and odors. It all depends on us and how much we want to explore.

Sparkling and refreshing beverage that contains some alcohol (but not more than 1.2%).
Think of it as a cold soda or a cold beer. In fact, think of it as a combination of those two beverages.
The term kvass is of Slavic origin and literally means “sour drink”, which describes it quite well.
If we examine its history, its origins remain unclear. But it’s clear that traces of it can be found in Egyptian stories from 8000 years ago, where a drink is mentioned that was made from baked bread to which yeast, various herbs and tree bark were added.
One of the oldest records of the term kvass can be found in “Tale of Bygone Years”, in which it says that Vladimir said in 989: “Give food, honey and kvass to people”.
The conclusion of it all is that kvass has been around for a very, very long time.
Of course there are also different theories regarding its origin and popularity.
According to one theory, people started drinking it in large quantities due to a lack of drinking water at the time, while another theory claims that yeast was actually considered to be food, it would keep people full and that’s how they survived and didn’t feel hungry.
Both theories sound realistic and an important fact is that kvass as such remained a Russian product and its national drink, right up there with vodka.
Literally everyone drank it, from servants, soldiers, doctors… and its significance is best described by Pushkin’s statement: “And like fresh air, they love their kvass”.
Every family had their own recipe for this drink and so do we 😊

To make it, we need water, sugar, bread and yeast.
·       Slice the bread and toast it lightly.
·       Boil some water and add 5% sugar.
·       Put the toasted bread in the water and let it cool overnight.
·       Strain the bread the following day.
·       Add yeast.
·       Pour in jars for primary fermentation and leave the kvass in the jars for three to five days.
·       Then fill the kvass into airtight bottles and add a little sugar to encourage secondary fermentation. Leave in jars for two days.
·       Place the jars in the fridge and let cool for 24 hours, after which it is ready for serving and consumption.

„In a world full of soda, be a kombucha“
Popular fermented drink whose fermentation can be credited to black or green tea, sugar and SCOBY (remember and return to the beginning of the text, if necessary 😊).
Lightly carbonated depending on the duration of fermentation, the flavor may be sweet or bitter. If it’s fermented too long, kombucha can lose almost all the sugar and the flavor can become vinegar-like.
Some like that sort of flavor very much and are very happy and satisfied with it, so the final product depends solely on our preferences.
Because of the fermentation process, kombucha contains some alcohol, mostly up to 0.5%. It’s good for digestion and the tea that serves as its base provides caffeine and antioxidants.
As for the history of this elixir of health and longevity, it’s quite simple. It emerged about 220 BC in China and over the centuries it made its way to eastern and central Europe via Russia.
During World War II it disappeared due to the lack of sugar and tea, which are the basics of its production, but it gained new popularity in the United States in the late 20th century and then spread to Europe, where all its benefits for human health were recognized.
But what’s most important is the fact that you can make kombucha on your own, at home, in a bar, in your kitchen, according to your preferences and the flavor that suits you.
What you will need to get started is SCOBY.
You can buy it online, grow it yourself, ask a friend or ask us to give it to you (which is a great idea 😊).
We make our perfect kombucha flavor as follows:
·       First take the ready kombucha out (the kombucha we made last time) and fill it in airtight bottles.
·       Thoroughly inspect and wash all SCOBIES.
·       Make some tea using two types of organic tea: Dian Hong Jin Hao (black tea from China’s Yunnan Province) and Wuyi Oolong (oxidized green tea from Fujian). Steep each tea three times.
·       When the tea is ready, add 10% sugar.
·       Pour into jars.
·       Add some “old” kombucha, sweetened and chilled tea and finally the SCOBY.
·       Cover the jars with gauze and secure with a rubber band.
·       Leave in a dark and warm place for 10 days.
·       And then repeat everything from the beginning 🙃

·       All jars and containers in which you make tea or store SCOBY must be thoroughly washed and clean without any traces of detergent and the like.
·       The SCOBY must not sink to the bottom of the jar (this is an indicator that something is wrong with the SCOBY or that it is “sick”).
·       The optimum temperature of the tea into which the SCOBY is placed must not exceed 25 degrees

Although the fermentation processes of both drinks are similar, kombucha relies on the SCOBY in the fermentation process, while kvass uses lacto-fermentation and relies on natural sugars. The one thing that is common and sure is that these drinks are healthy and promote a healthy lifestyle.

One last thing!
Constant reading, learning, testing, searching, trial and error that happen along the way, that’s the world of fermentation. And it’s very interesting. Don’t be discouraged along the way, we’re always available for any questions.

Your Karlo and Natali

Karlo Ferenčak – Head Bartender at Noel restaurant
Natali Borić – Bartender at Noel restaurant