Making 100% rye sourdough may seem like the simplest deal containing only rye flour, water, and salt. What makes it challenging, though, is the nature of rye flour.
Rye has less gluten which makes the proof, rise, and shaping a totally different thing. With this rye sourdough FAQ post, I try to give further tips so that you can succeed with your baking.
There are hundreds of ways to bake rye sourdough. This post deals with baking 100% rye sourdough called HAPANLEIPÄ – a traditional wholegrain rye loaf originating from Eastern Finland.
CHECK the recipe for Finnish 100% Rye Sourdough here
Disclaimer: this post includes affiliate links, meaning that I get a commission if you choose to make a purchase through the given links. Read full disclosure here.


FAQ | How to bake 100% Rye Sourdough
Over the years, I’ve received many questions about baking this 100% rye sourdough bread on Instagram and via DMs. I will summarize the questions in the main areas of baking so that you can achieve the tasty 100% rye loaf you’re dreaming about.
This is not a chemistry class but a common-sense FAQ to have a closer look at different areas of the bake. You can read the full post or jump into the question of your choice via the links below.
Common questions about baking a 100% rye sourdough bread
- Where to find coarse whole rye flour?
- Can I make the hapanlepä with my wheat-based sourdough starter?
- Can I proof 100% rye loaf in the fridge overnight?
- Shaping the spongy rye dough feels impossible
- My rye sourdough bread is flat
Where to fin whole rye flour?
To bake a 100% rye sourdough, you need whole grain rye flour. Whole rye is rich in fiber & nutrients because the whole rye kernel is used in milling. You will notice that the whole rye flour is rather coarse and sandy. This type of flour does not only bring you health benefits but also builds up the texture of the rye dough a certain kind. Light rye or medium rye flour will only give you a dense loaf.
Usually, you come across three different kinds of rye flour: light, medium & dark rye flour. This may be a bit misleading to someone new to rye flour as dark rye flour is not actually “dark” in color. The difference is the amount of bran left in the flour after processing. Light rye flour has been usually sifted twice to remove the bran and germ, whole rye has all of the goodies. When baking 100% rye sourdough, choose labels like dark rye flour, whole rye or whole grain rye.
Where to find this type of coarse rye flour is a question where you’re located. Rye is a northern grain and it may not find its way to every supermarket in South America, for example.
But despite your location, I have three strategies for you.
- Is there an artisan bakery in your town? Ask bakeries for tips where to find whole rye flour in your area. Maybe they can sell you a flour bag for experimentation?
- Do you have an organic specialty store or a miller close by? Or can you order rye flour online?
- Ask a Finn. Rye bread is our national food and we miss it dearly whenever abroad. Whether it’s an organization e.g. The Finnish Seamen’s Mission or your cousin’s workmate, don’t be afraid to ask for information.
US | CANADA | UK | AUSTRALIA
In the US, many who have shared their baking process with me, have used Bob’s Red Mill Organic Rye* as a combination with another type of rye flour from some other brand. Also, Great River Organic Milling has organic stone ground medium-dark rye Flour* and it’s available in a 25-Pounds sack.
I’ve also found that New York bakers sell a variety of rye flours and the site has specific product descriptions. Have a look through the link, keep your eyes open for “whole grain” & preferably stoneground.
In Canada, I would check Flourist. A reader who baked my 100% rye sourdough recipe had amazing results with rye flour from 1847 Stone Milling. They ship free for orders over $80.
Here’s a New American Stone Mills listing from which you can check millers around your region. In addition to the US, also millers in Canada, Australia, and Europe are mentioned.
Chances are you don’t find the best rye flour right away so don’t rely on one rye flour brand only. You can use medium or light rye flour moderately. I recommend in the recipe to combine 2-3 different kinds of rye flour giving the whole grain dark rye the main role.
In the UK, one organic option could be Doves Farm 2 X 1Kg bag of wholegrain organic rye flour package*, which is just the perfect amount to start your rye baking adventure. I’ve also noticed that Shipton Mill is a trusted flour source among sourdough bakers. In addition to dark rye, you can substitute some of the flour with medium rye (for example Organic medium rye flour 1kg from Naked tree*).

Can I make the rye sourdough with my wheat-based sourdough starter?
Making the Finnish 100% Rye Sourdough grounds on making its own starter. This rye starter based “pre-dough” or sponge is called RASKI. It is made every time over 1-2 days before you bake the rye bread.
This pre-dough builds the aroma and distinctive lactic-acid heavy sour taste of the rye bread. The long pre-dough process is necessary, it’s the root of the delicious bread and gives it a long shelflife.
If you want to try, you can build the RASKI with a small amount of wheat starter. To build traditional RASKI, I have written a step by step guide on how to build a rye sourdough starter here. The recipe gives you the pre-dough or sponge leaving zero discard.
The photos in the rye starter post linked above showcase what you can expect from your first, young rye starter. When baking actively, overtime your starter will build complexity showing more bubbles and a spongy look. When your rye starter is strong, building the RASKI is more efficient and no extra whisking to support the fermentation is needed that much.
Whether you A) build the rye starter and pre-dough from scratch or B) turn a new one with the help of your wheat starter, be sure to dry a small amount of the rye dough for future baking.
Can I proof the 100% rye sourdough in the fridge overnight?
As mentioned above, the sourness and flavors are rooted within the pre-dough (raski). The bread is baked on the same day when the final dough is made. The problems with overnight cold-proof are twofold.
If you proof 100% rye loaf in the fridge, chances are that it will over-ferment. Secondly, the taste profile will end up being too vinegary. Rye dough likes to be warm.
The 100% rye sourdough rises on the table covered with a kitchen towel so that it won’t dry. No proofing basket is needed. It is easier for you to keep an eye on the loaf when it’s not hiding in a basket upside down. Also, the basket will prevent the fine crackling of the surface.
Shaping the spongy rye dough feels impossible
The wheat-based dough has gluten which makes the dough elastic. Rye flour has little gluten and hence it will not build viscosity. There’s not really too much muscle work required when building the rye dough for two loaves. Mixing the dough with a spatula and your hands are recommended methods. If you must use a stand mixer, work with the slowest speed and be careful not to over-work the dough.
When the pre-dough is fermented and the final dough is given enough time to rise and ferment, the dough will be easier to handle. If your dough has a significant amount of light rye flour, it will become wallpaper paste. Coarse wholegrain rye-based dough, on the other hand, builds on a complex set of starches. This results in a spongy and sticky dough mass which is manageable.


The old recipe that I use has a higher hydration percentage compared to other doughs I see around on the Internet e.g. Youtube. But in the shaping stage, extra flour is used. The work surface is dusted lightly multiple times so that the bread won’t stick on to it. The dough will, of course, take in that flour and become denser and easier to work with. The dough is ready when it doesn’t stick to your hands.
Don’t be afraid to use flour in the shaping stage. I emphasize that too much flour will result in a dense loaf, but this precaution should not stop you from finding the manageable texture with the amount of extra flour that the dough requires. It’s okay to shape again and spin the pyramid. As a plan B, you can always bake the dough in a bread tin.
You need to get to know the nature of your rye flour and your starter over time. Baking is the only way but luckily it’s a delicious journey. :)
My rye sourdough loaf is flat
In the rising stage, rye sourdough is supposed to flatten. How bizarre! You see, the dough is shaped with a high profile (think of a pyramid or a cone) and the sharp bread top will flatten during the rise. If your rye sourdough is flat within a couple of minutes of the shaping, the dough is too wet to hold its shape. Don’t worry, shape again with a little bit more flour.
Despite the counterintuitive proofing process, the loaf will rise into a dome shape again in the oven. If your bread doesn’t rise in the oven, the wild yeasts did not have enough power to rise. Keep a focused eye on the fermentation process & timing next time. The rye sourdough is ready for bake when the surface crackles enough. Don’t forget to punch holes with a fork or a BBQ stick before the bake.
Happy Baking!
I wanted to give thanks to everyone who has baked HAPANLEIPÄ – a Finnish 100% whole grain rye sourdough with this extra FAQ post to support new bakers. Earthy rye sourdough is a delicious and healthy choice worth exploring.
While baking rye sourdough is natural and easy for me here in Finland where countless small millers provide whole grain rye flour, I realize that is not the shelf situation in every other supermarket out there. Thank you for the photos and questions as well as flour spotting, keep them coming to help others.
Love, Saara
Did you bake 100% rye? Tag me along on Instagram or comment below :)
My Vintage cooking on instagram
The Finnish 100% Rye Sourdough Recipe
Making rye sourdough starter step by step
6
I am so excited to find your website! I was a foreign exchange student in 1981, to Eastern Finland. I have looked for recipes for many years for 2 things! Karelian pie and real sourdough rye bread. I come from a very Finnish part of the US. But never found the right look or favor. Just from the look of your recipes I have found the right stuff. Not sure when I’ll start to try my hand at these, but I have them now! Thanks again!
So wonderful to hear Michelle! I’m a fan of the rustic flavours of rye from Eastern Finland as well :) I hope you find the recipes useful and delicious, do let me know if you have any questions.
Saara
I’ve been baking 100% Rye sourdough and selling it to health minded people for a year. It’s problematic and I’ve been on my own so I need all the information I can get.
Hi Linda! The 100% rye loaf is a delicious and healthy choice for sure. I hope you found tips for the flour choices and baking techniques with this recipe. Do let me know how it’s going, I’m happy to help. :)
Saara
Golden Harvest Health food supermarket in Rhinelander Wisconsin makes a 100% Sourdough Rye that is very good.
Thanks for this tip :)