There are wide variations of Polish soups, many of which are made using ingredients widely available in Poland. One common ingredient in soups from Poland is zakwas. So, what is Zakwas, how is it used, and how can you make a zakwas recipe?
What Is Zakwas? How Is It Used?
Zakwas, also known as sour rye starter or rye flour starter, is a common ingredient in Polish soups. It is fermented rye flour that Polish cooks use to add thickness and a sour flavour to their soups. One of the best-known soups that uses a sour rye starter is zurek. Zakwas is also an important ingredient in some Polish bread, such as sourdough.
In Poland and some other European countries, rye flour starter is widely available in supermarkets, and most home cooks just buy the ingredient to use in their cooking. However, finding sour rye starter outside Poland is a little trickier.
Therefore, if you live in the UK, the United States, Australia, Canada, or elsewhere in the world, you may find this ingredient difficult to come across. On the other hand, if you live in an area with a large Polish community and a Polish supermarket, you might find the ingredient in your neighbourhood.
Is It Possible to Make a Zakwas Recipe?
You can make the zakwas recipe yourself to use in sour soups. It is a simple enough process, although it is time-consuming as it takes up to five days to ferment the sour rye starter before you can use it in soup or bread. You will need whole wheat rye flour to make the starter, preferably organic.
Zakwas Recipe: A Polish Soup Sour Rye Starter
Course: Recipes, Soup RecipesCuisine: PolishDifficulty: Easy5
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Ingredients for Zakwas
100g/ 7 tbsp wholemeal rye flour
500 ml water
4 garlic cloves
Directions: How to Make Zakwas
- Boil the water and leave it to cool.
- Sterilize a jar large enough to contain 500 ml of liquid, then make sure it is completely dry.
- Add the rye four to the jar, and add 3-4 tbsp of boiling water to activate the gluten in the flour. It should look like mud.
- Next, add the garlic to the mixture. If you are adding the spices, you should do so now.
- Pour the cooled boiled water over the mixture until the jar is almost full, and mix everything together with a spoon.
- Cover the jar with natural cloth, such as cheesecloth or muslin, to prevent bacteria from getting into the jar. Secure the cloth with an elastic band.
- Put the jar in a warm and shaded area to allow the mixture to ferment for four to five days.
- The zakwas recipe is now ready to use and should have a sour but pleasant aroma.
Notes
- Preprepared versions of zakwas have some flavourings added. You can add them yourself when you make the zakwas recipe or add the flavourings to the soup. If you choose to add the flavourings at this stage, you will need the following:
5 all-spice berries
5 black peppercorns
1 tsp marjoram
Additional Tips/ FAQs
If you have never made a zakwas recipe, you will likely have some questions about the process. Here, we have tried to answer your questions about how to make a sour rye starter.
How long can I store the sour rye starter?
If you keep the zakwas in a sealed jar or another container, you can store it in your refrigerator for up to two weeks.
Can I freeze zakwas?
It is not advisable to freeze zakwas. However, it is fine to freeze most soups that contain the sour rye starter, depending on the soup’s other ingredients.
Why is the zakwas thicker at the bottom?
Over the five-day fermenting period, some flour can settle to the bottom of the sour rye starter. It may lead you to wonder, ‘Can I use the zakwas if the flour has settled at the bottom?’ The simple answer is yes, you can still use the zakwas. One option is to stir it to even out the thickness. Alternatively, use the top half for a thinner soup and the thicker bottom sour rye start for a thicker soup.
Is there are gluten-free-version of zakwas?
People usually make Zakwas from wholemeal rye flour, which contains gluten. Therefore, sour rye starter is not gluten-free. However, all is not lost, and you can still enjoy sour soups if you follow a gluten-free diet, as there are gluten-free alternatives. The best option is to use buckwheat, which is gluten-free, to make the starter instead and then use it in your soups.
How Much Sour Rye Starter Do I Need for Soup?
The amount of zakwas you need for soup depends on the quantity of soup you make. It is important to note that the more sour rye starter you add to the soup, the sourer it will taste. Therefore, it depends on your personal preferences. Add a little of the zakwas and see how it tastes, then add more if you want more sourness to the soup. As a general guide, 10 tbsp will give the soup a mildly sour flavour, while 15 tbsp will give a stronger sourness to the soup.

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