Looking at different websites I found sourdough starters using potatoes instead of wheat or rye. They all used cooked mashed potatoes.

I wonder if it is possible to just grate raw potatoes or other starchy vegetables and use them. I still have some self-made wheat sourdough starter at home. So I could mix a bit of that with my grated potatoes.

Has anybody here tried before?

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    What is the problem in cooking the potatoes? Anyway look for Rewena bread recipes. It is a super yummy Maori sourdough bread that uses potatoes. – nico Jul 13 '11 at 10:20
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    @nico, suggesting rewena was very helpful. I found descriptions for potato only starters there. However I am still interested in raw potatoes, as this is only the first step. Later on I want to be able to make bread from different vegetables, preferably without cooking them twice. I could image, a sweet potato bread or a carrot bread from drained carrots could be possible. But I am not there yet. – Amelse Etomer Jul 13 '11 at 11:27
  • Just to give a little update, using cooked potatoes worked well so far. Making a bread consisting only of potatoes did not work. I was too moist. Next, I'll try to microwave the potatoes, so that they don't have a chance to soak up water. No luck with raw potatoes yet. – Amelse Etomer Jul 31 '11 at 9:22
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    Are you trying to make bread with just vegetable matter and no flour? And what is the detriment that you're trying to avoid by not cooking them twice? – SourDoh Nov 13 '13 at 21:21

Yes! I'm currently attending Le Cordon Bleu for Baking and Patisserie. I'm in the breads class right now, and my text book has a recipe for a potato sour with raw potato. Here..

8 oz Bread Flour 6.5 oz Warm Water .16 oz (1 tsp) Salt .16 oz (1 tsp) Sugar 1 Large Potato, peeled

  1. Mix together the flour, water, salt, and sugar into a smooth soft dough. Add potato.

  2. Place in sterilized bowl. Cover tightly with muslin or other clean fabric so the starter can breathe. Let rest in a warm place for up to 24 hours, until the mixture becomes frothy.

  3. Stir well and cover with plastic film. Leave to stand 2-3 days in a warm place, until the mixture becomes light and foamy. Stir thoroughly each day.

  4. Pour the fermented starter to a glass jar and store in the refrigerator for approximately 3 days, or until a clear liquid collects on top of the mixture. This indicates the mixture is ripened enough for use.Carefully pour all the liquid collected on the surface into a measuring jug, discarding the solid mixture that remains on the bottom. The weight of the liquid should be greater than the weight of the water used, because some of the flour will be poured off with the liquid.


In a sourdough starter, the bacteria and wild yeasts feed on starch. This is why bread is usually made from grains, which are very high in starch. Potatoes are one of the very few vegetables which have enough starch to work in a bread. So the idea for a bread from other vegetables won't work. Sweet potatoes could be OK, but definitely not carrots. You could look into the starch content of other tuber vegetables to determine if there are some good enough for your purpose.

As for the raw part, I highly doubt that it will work, again because of the starch. It is present in the raw potatoes, but it is enclosed in the cells, behind cell walls of celulose. When cooking, the cell walls soften and burst (this is why a cooked potato is soft and a raw one is firm) and the starch is released, so it is made available for the sourdough fermenter organisms. I am not 100% certain that it's impossible, but let's say 90%.

If you want to create a dough with a high proportion of vegetables, you could use normal sourdough starter as barm and when making the final dough, use pureed vegetables (raw or cooked) or a vegetable juice instead of water (after adjusting for thickness). If you think that you can get interesting fermented flavors from adding the vegetables to the starter, you can again use them as the liquid in the starter, not as the flour. But I am afraid that fermented vegetables will taste unpleasant, similar to vegetables gone bad after being forgotten somewhere. Still, it could be an interesting experiment.

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    In terms of releasing the starch, you might be able to juice potatoes and break down enough cell walls. This only makes sense if you're trying to avoid cooking twice for nutritional reasons. – rfusca Feb 21 '12 at 18:06

My mother-in-law has been baking her own bread for almost 60 years using yeast made from raw potato. She usually takes a medium-sized potato, grates it coarsely and mix it with about 3 desert spoons sugar and 1 desert spoon salt and warm water in a glass jar. This is left in a warm place until the mixtute becomes foamy. A couple of raisins could be added to speed up the process. The liquid which would serve as the yeast, is then drained off and added to the flour. The remaining grated potato should not be discarded as this becomes the starter for the next batch of bread. It should be stored in a container in the fridge until needed.


Yes, you can do it it, but you'll need to cook and mash/puree the potato first. The cooking inactivates the potato's enzymes, breaks down the potato cells, and kills the spoilage microbes present in the raw potato. When combined with cooking, pureeing finishes breaking down the potato's cells and makes their starch and sugars accessible for your sourdough to digest. Oh, and retain part of the starchy water from cooking the potatoes; you will need this to make the mixture wet enough for the sourdough, and the extracted starch gives them more available food.

As with all changes in sourdough feed, make the change-over gradually; start feeding the starter with a batch of half-flour, half-potatoes, and then switch over to just potatoes after a few feeding cycles. This will make it easier for the yeasts and bacteria in the starter to adjust to the change.

To get proper results with other vegetables, you'll need a lot of starch content. If you cannot get a flour made from the vegetable, I wouldn't expect a sourdough to live on it. Sweet potatoes and parsnips should work. Chickpeas, beans, peas, and lentils may work if cooked well (retaining as much starchy water as possible) and pureed. With all these vegetables, cooking and pureeing is suggested.

The yeasts in sourdough can also ferment sugar-heavy vegetables, such as beets, carrots, onions, or tomatoes, but the results are similar to sauerkraut or kimchee. Don't expect the starter to thrive and propagate using these foods, but it may make for an interesting experiment nonetheless.


Foodgeeks has a sourdough starter recipe featuring grated raw potato. It still calls for white flour in addition to the shredded potato bits. I haven't tried it, and it's unreviewed on their site, so your guess is as good as mine about how the starter turns out.

So, to answer your question: No, it seems that nobody on here has tried it before. Try it and report back - you could be the first!

  • That sounds interesting. I'll mill the potatoes very finely to brake down some of the cell walls and then hope that fermentation commences. – Amelse Etomer Jul 15 '11 at 0:45
  • Let us know how it goes. Good luck! – hairboat Jul 15 '11 at 12:44

Im a little late on this debate. However, my husband tells me that his grandmother used to make her bread starter with potato peel and lemon juice. Once started, this culture used to sit in a warm place and be fed sugar and probably flour regularly. Bread was made each day for the family. How are you going 3 years on with your experiment. I'm interested in doing something like "grandma" used.


My grandmother put a whole raw potato in what appeared to be a typical sourdough starter otherwise. She kept it in her refrigerator and made biscuits with it regularly. The potato stayed in the starter. I wish I would have known I needed to ask her some questions about this before she passed...I don't know if she switched out the potato or how often if she did, or how she fed the starter, but I do know she made some dang good biscuits.

  • Interesting. Was the potato completely smothered by the rest of the starter? Or was part of it sticking out above the level of the starter? – Jolenealaska Nov 10 '14 at 3:51

I'm basically ignorant in most of this, but logical in other ways.

If sugar is being added to the starter mix, I suspect that defeats the idea of how the "old People" did it... their access to refined sugar would have been limited. (Especially Country folk) I know of these such instances where nothing but potato water was used to feed the starter.

Two thoughts come to my mind: 1) if sugar is used, then sugar dependent Wild Yeasts that are present in the Culture are being activated. 2) If only Starch, (not sugar) is causing fermentation then we are on track. That then suggests that an enzyme (in a symbiotic relationship with a particular Yeast type) is present. This enzyme converts the starch to the sugar that feeds the yeast.

I'm thinking this line of thought backs up the idea that the "old Folk" were using uncooked potato in the CULTURE mix. Cooking in any shape would destroy the relevant enzymes.

Summary: Wild yeast plus "Natural" enzyme plus accessible (Cooked) potato starch = The Potato Sourdough Culture everyone is after.

Therefore we should, maybe stick with the formulae using Raw potato as the basis of finding the the appropriate Bio organisms that create the majic.

Hope that all makes sense.


Bernard Clayton has a raw potato starter in his "Complete Book of Breads".

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    Hello and welcome to the site! You could even improve your answer if you could add your own experiences (OP asks: "Has anybody tried before?") or paraphrase the key points of the book you mention. – Stephie Feb 10 '15 at 10:15

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