The Bread Matters Sourdough Starter is rye flour and water in which naturally-occurring yeasts and bacteria have developed and been nurtured over quite a few years. Wholemeal rye flour is especially rich in these micro-organisms, which is why, if you want to maintain only one sourdough starter, it makes sense to make that a rye one.
It is easy to use a rye starter at any time to make wheat bread. Just bear in mind that if you want to keep a pure rye starter on the go as well, you should not use it all up in making the wheat bread described below. If you do, you will have to start a new rye sourdough. If you don’t mind ending up with a mixed rye-wheat starter, you can simply refresh your initial starter with wheat flour and take it from there.
If you are starting with the Bread Matters Sourdough Starter, i.e. the 10 gram dried sourdough in the cellophane packet, start at A.
If you already have a rye starter that has been refreshed once and thus bulked up to at least 100 grams, start at B.
A. Initial activation of the dried starter
10 g Bread Matters Sourdough Starter (dried)
30 g Wholemeal (‘dark’) rye flour
60 g Water (at about 35°C)
100 g Total
(We used to supply the sourdough starter as a hard biscuit. It is now supplied as a powder. The mixture hasn't changed, just the way it is processed. The photos below still show the old form.)
Add the 10 grams of powdered sourdough to 60 ml of warm water (or a little more if necessary, stir well and soak for 2-4 hours. Add the 30 g of rye flour and mix to a sloppy consistency, adding some warm water if required. Cover well (to keep the moisture in and unwanted organisms out) and leave in a warm place (but not directly on a stove or radiator) for 12-24 hours.
After a while the mixture should bubble a little, perhaps even frothing a bit and then subside. It will smell slightly acidic – fruity rather than vinegary. Don’t worry if a layer of grey liquid appears on the top towards the end of this fermentation period.
This is the sequence:
1. What’s needed: Sourdough Starter, warm water, dark (wholemeal) rye flour, small mixing bowl
2. Slit the envelope to reveal the instructions. You can compost the film that the starter disc comes in.
3. Crumble the starter into the bowl
4. Pour on warm water (35°C). Leave for 6-12 hours.
5. Work the starter and water together until a smooth mixture is obtained.
6. Add the requisite amount of dark rye flour, mix thoroughly until a sloppy mixture is obtained (some more water may be needed at this point to keep the mixture loose enough).
7. Working sourdoughs by hand can add beneficial bacteria to the mix.
8. Mixed and ready to start fermenting. The texture should be like thin porridge.
9. Cover with a polythene bag to prevent the surface drying out. Put in a warm place (not more than 30°C)
10. After 12 hours or so, it might look like this. It has begun to bubble a little, but is not very active yet. Give it a few more hours in a warm place.
11. A close-up of an active starter after refreshment. The bubbles are yeast activity and will subside gradually to leave a flat surface, often covered with a thin layer of grey liquid. This is normal.
B. Making a wheat Production Sourdough [PS] or ‘Production Leaven’
80 g Sourdough Starter (e.g. rye starter from above) *
200 g Wholemeal wheat flour
100 g Water (at about 35°C)
380 g Total
* That should leave about 20 grams of pure rye starter. Keep these 20 grams in the fridge until you want to make more rye bread or refresh it now to be sure of having enough in the fridge when you next need it.
Mix everything together into a soft dough. Cover and leave in a warm place for 4 hours or until it has roughly doubled in volume. Then use this Production Sourdough to make your final dough.
C. Wheat Bread Dough
300 g Refreshed Production Sourdough**
400 g Wheat flour (wholemeal, white or a mixture)
8 g Sea Salt
300 g Water (at about 30°C)
1008 g Total
** You will be left with about 80 g of Production Sourdough which is a hybrid of wheat and rye. Keep this in the fridge in a separate tub until you next refresh it to make bread, or add it into the remains of your rye starter, but remember that this will no longer be pure rye.
Make a dough with all the ingredients except the refreshed PS. Knead until the gluten is showing good signs of development. Then add the refreshed PS and continue kneading for a few more minutes. At the end of kneading the dough should be soft and stretchy and coming away from your hands, but it should not be so firm that it doesn’t stick to the worktop if left for a few seconds.
Dust a proving basket with brown rice flour (or wholemeal wheat flour). Form your dough piece into a rough round and, keeping the tucks uppermost, dip the dough in a bowl (or puddle) of the same flour so that at least the bottom half of the dough is covered in flour. Place it in your floured basket and flick a little more flour on any surfaces that might get stuck to the basket. Cover loosely with a polythene bag and leave to prove in a draught-free place for 3-4 hours.
When you tip the proved dough out of its basket on to a baking tray or peel (a baker’s flat shovel for sliding loaves into the oven), mark it with whatever cuts take your fancy. Bake in a fairly hot oven to develop a really good crust.
Alternatively, mould the dough piece up tightly and put it in a baking tin (or two small ones), aiming to fill the tin(s) about half full. Cover and prove until the dough is nearing the top of the tin or is beginning to feel a little fragile when gently pressed with a flat finger.
Bake in an oven that is pre-heated to 230°C (or as hot as the controls indicate) for ten minutes, then lower the temperature to 210°C and continue to bake for about 30 minutes. The loaf should have a firm deep crust which cannot easily be depressed. This will gradually soften as the loaf cools and the moisture in the internal crumb migrates to the surface.
This recipe appears (with minor differences) as Cromarty Cob on pp 198-200 of Bread Matters.