About Rye Malt for Kvass


In English: Making Red Rye Malt (see comments)

Simplified Summary

Red rye malt is a Russian term for non-diastatic malt that is very important in building kvass flavor profile. It looks like none of available in the U.S. rye malts can be its 100% substitute. The closest one is crystal rye malt, which is described later.

Red rye malt goes through an additional fermentation process. It is performed on the forth day of grain germination. The process occurs at a high temperature of 55-68°C/130-154°F without access of air. At the end, the content of fermentable sugars and amino nitrogen increases five times. This step is very important and results in a specific taste and color of rye malt. Fermentation takes place in heaps of grain. For four days, various physical and biochemical processes change the undisturbed grains. After the first two days, the heap separates to four layers. The second and partially third layers of the heap are used for red malt production. They are dried, sifted to remove sprouts, and milled. The ground red rye malt should rest for 30 days to develop its best flavor.

Crystal Grain

“The terms Crystal malt and Caramel malt are used interchangeably to describe a type of grain that undergoes a special stewing process during malting resulting in a crystalline sugar structure inside the grain’s hull.”

This recipe is based on Crystal Rye Malt by Simpsons and rye sourdough starter. Flavor complexity of this drink is somewhat in the middle between kvass made of regular rye bread and special kvass bread. Filtering the extract is a bit challenging, but other than that the recipe is pretty simple and straightforward. Since crystal rye malt is non-diastatic, we need to add sugar to the extract. This batch was the least active of all I’ve made so far.

Crystal Rye Malt Kvass
Crystal Rye Malt Kvass

Kvass Batch 4 [Crystal Rye Malt]

Prep Time5 mins
Total Time13 mins
Course: Drink
Cuisine: Eastern European
Keyword: drink, kvass, lycooking, lyukum cooking lab, recipe
Servings: 5 quart


  • 160 g crystal rye malt grains
  • 5 quarts water
  • 100 g agave syrup
  • 40 ml rye sourdough starter


Step 1: Making Malt Extract

  • Mill crystal rye malt.
    Crystal Rye Malt
  • In a large non-reactive container, mix crystal rye malt flour and 2 quarts of hot (80C/176F) bottled drinking water (do not use tap water! there are chemicals there that might kill fermentation process). Steep for about 2 hours in room temperature.
    Crystal Rye Malt Extract
  • Strain the extract.
    Straining Crystal Rye Malt Extract
  • Then filter it. This step is time consuming and requires a few changes of paper towels (unscented!). Add agave syrup and cold drinking water to make total 5 quarts of extract.
    Filtering Crystal Rye Malt Extract

Step 2: Fermentation

  • Check the temperature of rye malt extract. It should be 30C/86F. Dissolve rye sourdough starter in 1 cup of liquid, stir, and pour it back into the pot.
  • Keep at room temperature (72-74F) for about 2 days. It takes 12 hours when the temperature is 86F. At lower temperatures, fermentation process takes longer. See the picture for how fermentation activity looks like — almost no bubbles. Test by tasting.
    Fermenting Crystal Rye Malt Extract
  • Prepare clean screw-cap or flip-top bottles and funnel.

    When bottling kvass, make sure the sediment on the bottom of the jar where kvass was fermenting is not disturbed. To carbonate kvass during the next step, conditioning, feed it with some agave syrup right before bottling. Add 2-3 small raisins per 1/2 quart of kvass. Seal the bottles.

Step 3: Conditioning

  • Condition bottled kvass at 45-50F temperature for at least 3 days or up to 7 days (wine refrigerator is the best).
  • After conditioning, store bottles refrigerated. It is good for drinking for the next 2-3 weeks. The longer it is stored, the more tartness it will develop, because it's alive. By lowering down the temperature, we only slowed down the fermentation, we didn't stop it. Keeping bottles upright helps to clarify kvass.
    Crystal Rye Malt Kvass


Experimenting with Kvass in Texas
Do not use yeast only — you'll get a beverage with much higher level of alcohol and unpleasant aroma (been there done that!). If you bake your own bread, start making your kvass when you have 1-to-3 days old dough in your refrigerator. If you don't, buy a portion of sourdough starter in your favorite bakery.
The sediment on the bottom of the jar where kvass was fermenting can be used as a kvass starter. It is not safe to use it for more than 2 to 3 batches. When using kvass starter, plan in advance. Have your next kvass bread extract ready by the time your currently fermenting kvass is ready to be bottled.
A good seal is needed to withstand the pressure build up in the bottle that gives the beer it's carbonation. I use flip-top beer bottles. The rubber seal of flip-top bottles can't hold the pressure over long periods of time. They are good enough to condition kvass for a few days, easy to clean, and you will never loose the flip-top. The rubber seals can be replaced over time. These bottles are cheap and easy to find. For a couple of bottles, look for good deals online or in Home Goods/TJ Maxx/Marshals/Hobby Lobby, etc. Since kvass is conditioned for a relatively short time period, dark glass is not important.
My favorite sugar and flavoring ingredient is D-180 Candi Syrup. It can be found in many beer brewing supplies stores.
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Crystal Rye Malt Kvass