Kvass: Fermented, fizzy and flavoursome
"The Czech beverage market is quite conservative, but I think kvass will soon make an appearance. After the kombucha wave, we will taste something new again," says Zuzana Ouhrabková from the blog Zkvašeno and reveals the origin of a Slavic drink with a thousand-year history: "In Ukraine, Russia or Lithuania, but also in other countries of Eastern and Northern Europe, different types of kvass are still traditional today. The most famous, however, is certainly the one made from bread."
Upcycled lemonade
The preparation of bread kvass is not demanding in terms of raw materials, and the essential role is played by (older) breadwhich is dried and toasted beforehand. "The recipes usually state rye bread, ideally containing rye malt, which gives the kvass its body. The bread is then sliced thinly or cubed and baked for 15 to 30 minutes in an oven heated to around 160 °C, so that the crust caramelises and imparts maximum aroma and flavour to the kvass,' says Zuzka. "A good quality light pastry made from wheat or other flour will also do the job, but such a drink tends to be weaker in taste."
Step number two - infusion
Baked to a dark brown, the pieces of pastry are combined with boiling water in a 1:2 or 1:1 ratio and simmer until the next day. "In the first stage, the basis of the future kvass is formed, i.e. water infused with bread. It should be completely submerged, weighed down with a plate. In addition, the container is covered with a cloth to protect the liquid from insects," recommends Zuzka. "It needs at least 24 hours. Only then is it drained through a fine sieve and cloth and can be worked with."
Next up is fermentation!
All sorts of yeasts are responsible for the production process, which takes care of fermentation in the demijohns or bottles. The infusion from the bread is fermented either spontaneously or with the help of sourdough (made of flour and water) and yeast. "I use rye yeast as a starter, which starts fermentation in time, both alcoholic and lactic. I add it either to the cooled bread or to the leavening brine together with other ingredients," says Zuzka, explaining:
"The leachate releases some of the starches from the bread, but for the fermentation to proceed properly, carbohydrates in the form of sugar, honey or fruit must be added. Ordinary yeast or ground malt will also help the fermentation and specific taste. In Ukraine in particular, it is common to make home-made kvass from rye malt.'
Remark: The fermentation process can also be started with water kefir or a certain amount of ready-made bread leaven.
Sugar is scarce!
The kvass ferments in combination with herbs, spices and fruit to profile the varied flavours. "It's an East Slavic drink, so it was usually mixed with whatever was on hand. It includes raisins, berries and other seasonal fruits, and spices à la Coca-Cola, i.e. cloves, star anise, cinnamon or coriander," says Zuzka, and she goes on to suggest other variations:
"Mint, aniseed, rosemary, basil and ginger are also used for flavouring, as are wild herbs such as spearmint, which contains coumarin with hints of vanilla. The juice and zest of citrus fruits, or even a whole lemon, add acidity and a slight bitterness. It is mixed directly in the ferment.'
Bubbles at the end
Yeast works fast, in two to three days, the finished kvass will bubble up in a closed container. "Fermentation has to stop at the right moment, when the drink starts to bubble slightly. Otherwise, it can turn sour and lose a lot of flavour," says Zuzka. "In the end, the kvass is stored in a cool place to stabilise it. However, as with all natural ferments, it's worth storing the drink in the fridge and drinking it as soon as possible."
The story of kvass
In Eastern Europe, kvass has seen its rise as an iconic drink that later competed successfully with Western Coca-Cola. "As children, we drank kvass every day. I remember tankers driving through the towns, going through the backyards of houses and bottling it for the locals," recalls Ukrainian Alex Martynov, who runs a bistro The Borscht in Vinohrady, and continues:
"Bread kvass used to be fermented in every Ukrainian household. Like kombucha, in our country it was called 'tea mushroom'. Beet kvass was also aged in wooden barrels and is still used today as a base for borscht or sweetened and drunk as lemonade."
In time, home-fermented kvass gave way to industrially produced alternatives. These, however, lack liveliness and character. "Commercial bread kvass is made by first boiling and fermenting a malt-rye mash, then diluting, sweetening and sometimes finishing. The beverage is either left to ferment for a while or it is pasteurised, saturated with CO2 and infused," Zuzka describes.
In contrast to large-scale production, there are a number of modern companies that are returning to the original leaven, while innovating recipes and uses in the kitchen. "Kvass has always been used to make porridges and soups such as okroška or botvinja, but in recent years there have been more and more small producers and cooks who are trying to use it in interesting dishes. Some people, for example, bake meat in it or poach fruit," says Alex.
Pity about good bread
The potential of sourdough bread is also being liquidised by the Fermentalists, a group of sommeliers and enthusiasts who have decided to process Eska bread. "It seemed like a big waste of a good raw material, so we tried to use our long experience with wine, especially natural wine," explains sommelier and Winegeek team member Dragan Bogdanovic who previously worked for La Degustation:
"The theory goes that kvass is a living organism that is reflected in the taste of bread, similar to the terroir in grapes and subsequently in wine. We wanted to test this with practice, so we moved from an improvised space in the back of La Degustation restaurant to the cellar at Palmovka, where we set up a small 'laboratory'."
The idea matured into a unique edition of bread kvass. "We experimented with primary finished and unfinished fermentation (pét-nat style), but also with secondary fermentation in the bottle. We have about fifty bottles of the ferment which has been on the lees for almost 14 months. It has been given the internal name 'kvassagne'. Together with my colleague Mark Tříská we have managed to make a lot of more and less interesting bottles and we are about to release them to the world," reveals Dragan.
Extra trivia:
Bestselling fermentation author Sandor Katz publishes a simple recipe: He adds a pinch of salt, 125 ml of honey or sugar, the juice of one lemon and 125 ml of sourdough starter (or a packet of yeast) to 4 litres of bread and mint liquor. The mixed mixture ferments for about two days. The raisins help to judge the fermentation time. As soon as they rise to the neck of the bottle, it means that the ferment is sufficiently saturated with natural carbon dioxide.
Strong spicy yeasts are opposed to less pronounced white yeast, its delicate flavour is influenced by the sourdough starter of wheat flour, water and yeast, uncaramelised rye malt and buckwheat flour.
Pour the leavened bread kvass onto roast pork ribs.
Advocates of kvass claim that rye and barley malt drinks boost metabolism and, as a product of lactic fermentation has a beneficial effect on the gut microbiome and the cardiovascular system.
In addition to kvass based on bread and malt, there are pure fruit-based kvass from apples, cranberries, cherries, strawberries and mulberries, currants and raspberries, as well as vegetable variations. One part vegetable fermented with two to three parts water and 2 % salt. The remaining liquor flavours soups, sauces and dressings, or is sweetened and drunk as a drink. The fermented juice of celery, carrots and parsley can also flavour tomato and other classics.
In the past, kvasses were made with birch or maple sap, which was fermented with dried apples, pears and a little honey. Roasted barley was also added to large clay pots. It has fallen into oblivion, along with the fermentation of whey and honey.
In the Podkrkonoší region, there is a preserved record of the so-called "breberka". A few handfuls of dried bread and half a kilo of sugar were put into a pot, boiled in six litres of water and left to stand for eight hours. The mixture was then poured into wide-mouthed bottles, covered with a piece of cloth and fermented in the heat for about three weeks until the sludge had settled to the bottom. In some places the drink was bottled clean, in others it was supposedly eaten for breakfast.
Source: Zkvašeno.cz, The Borsch bistro, Fermentalisti, Katz
