Sourdough in the Height of Summer

The long rainy season has finally lifted and summer is here. It seems marginally less brutal than most years, but it is still hot. I do badly in the heat, and my motivation for most things sags with it.

When the temperature is high it is hard to judge the timing of fermentation, the dough goes slack, and things generally do not go well — so the pace of baking tends to drop off. On top of the heat, the sourdough I have been making with rye flour and wholemeal spelt has been stubbornly refusing to come right, and I had rather stalled.

Why My Sourdough Didn't Rise

There have been failures like this one, too...

Baking Sourdough on Hot Days

While I was struggling to get any rise at all, a reader left a comment, and this time I baked using the recipe they shared. It came out astonishingly well — so if you are having trouble baking sourdough in hot weather, this is worth a look.

Step 1 — Preparing the sourdough starter

This is the rye and whole wheat sourdough that has been giving me trouble. The starter is a rye and whole wheat one as well.

Between baking less often in the heat and alternating with bread flour loaves, this starter has not seen much use, and I had also let the feeding slide for about two weeks. The culture had lost a good deal of strength.

So I began by reviving it over two days of feeding. Scoop off and discard the top of the starter, then add 20g of rye flour, 20g of spelt and 40cc of water. Mix well, leave at room temperature for about two hours, and once it has risen a little, move it to the fridge. Feed it again the next day in the same way and give it one more day in the fridge for the culture to come back.

I used a new canister from Muji this time. It is compact, and because the diameter is constant from top to bottom you can see at a glance how far the starter has risen. Very easy to work with. 350ml, for reference.

What you need:

• Starter
• Rye flour40g
• Wholemeal spelt flour40g
• Water (around 20°C)
• Silicone spatula
• Storage jar

Two days was enough to bring the culture properly back. A rye and whole wheat starter left for a long stretch can darken at the top. From what I could find, this is ammonia forming, which turns the colour dark. It is not a problem in itself — discard the top and feed it as usual and all is well.

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Step 2 — Making the dough

Between the heat and the flours I have been using, rye and whole wheat sourdough has been giving me real trouble lately. The recipe here follows a comment left by a reader of this blog.

The key is this: ferment in the fridge through the stretch and folds, then do the second proof, after shaping, at room temperature.

Ingredients:

• Starter60g
• Bread flour (Kitanokaori)190g
• Rye flour30g
• Wholemeal spelt flour30g
• Water (around 20°C)165cc
• Salt4g

Mixing the dough

1. Put the measured water, the starter and the salt in a bowl and stir until fully dissolved.

2. Once mixed, sift the combined flours into the bowl from step 1 and mix. Start with the scraper, turning the flour up from the bottom of the bowl. Once it is roughly combined, use your hands to bring it together into a single mass.

3. Cover the bowl and leave it at room temperature for one hour. You are not building gluten by kneading; you are building it by waiting.

Stretch and fold

4. The first stretch and fold. It is exactly what it sounds like: stretch, then fold. Working around the round of dough, stretch and fold it roughly four to six times. Not kneading — stretching and folding. That is the point.

5. Cover the bowl and leave it in the fridge for 45 minutes.

6. Repeat steps 4 and 5, for five stretch-and-fold sessions in total.

Even with the bulk ferment in the fridge, it rose well. And the dough was not sticky — a very different picture from the earlier failures.

Shaping the dough

7. Using the scraper, ease the dough gently out of the bowl onto a floured surface. Flatten it lightly into a rough square, fold it in from all four sides, shape it loosely, and let it rest for about 30 minutes.

8. Finally, stretch and fold about four more times to build tension across the surface, and shape it into an oval. Dust the top with flour and place it in a cloth-lined banneton, turning it over so the floured surface sits at the bottom.

9. The final proof. About three hours at Room temperature should roughly double it.

The dough was not sticky and had good tension — far easier to shape than in the earlier failures.

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Step 3 — Baking

10. Put the Dutch oven in the oven and preheat to 250°C.

11. Once it is up to temperature, move the dough onto baking paper and make the score.

12. Lower it into the Dutch oven on its paper, put the lid on, and bake at 230°C for 25 minutes.

13. Take the lid off and bake at 240°C for a further 5 to 10 minutes.

The flavour and the texture were beautifully balanced. The best sourdough loaf I have baked.