## Sourdough experiment #3 170606 Hydration

Background

There is often talk on the forum (link) about the hydration of doughs, and the advantages and disadvantages of higher or lower hydration.

Hydration refers to the proportion of water in a dough relative to the amount of flour. It is usually expressed in terms of percentage of total flour weight. To calculate hydration add up the weight of all of the liquids in the dough (including water in the starter), and divide by the total weight of flour in the recipe (including that in the starter). Multiply by 100 to get a percentage.
My standard loaves are about 70% hydration. More than that starts to get pretty tricky to handle. Bill swears by doughs at about 64%.

Although it is a question that I suspect many will already know the answer to, I thought that it would be interesting to make my basic recipe with different proportions of water.

Aims

To determine the effect on oven spring, loaf crumb and texture of varying hydration in a standard white sourdough recipe.

Methods

As in previous weeks I used the Pane Francese recipe using my starter at 100% hydration. I made 4 half recipes (ie using 250g flour).

In loaf #1 I used 150g water

(Total water = 150 + 45 (in starter) = 195g

Total Flour = 250 + 45 (in starter) = 295g

Hydration = 195/295 x 100= 66%)

Loaf #2 = 160g water = 69%

Loaf #3 = 170g water = 73%

Loaf #4 = 180g water = 76%

(NB I did the recipe from memory, and forgot the small proportion of wholemeal flour - so the loaves this week were purely white)

This week I refreshed my starter twice at 12 hour intervals. On Friday morning I mixed the dough (three quick kneads at 10 minute intervals), then put it in the fridge. Friday evening I took the doughs out of the fridge and let them prove for about 4 hours at room temperature. They were probably a little underdone at this stage (relatively few bubbles on slashing), but I was going to bed, so shaped them, wrapped them in towels, and left them on the balconey outside my bedroom overnight (9 hours).

Baked the next morning. Single slash down the centre to minimise differences between the loaves.

Results (click on thumbnails for larger pictures)
The four loaves (left to right #1 to #4)

Loaf #1 (66% hydration)

Loaf #2 (69% hydration)

Loaf #3 (73% hydration)

Loaf #4 (76% hydration)

Conclusions

There were some clear effects of dough hydration on loaf structure and crumb.

The lower hydration loaves opened up much more with slashing. (I attempted to minimise differences in slashing depth by setting my Stanley knife to make a 0.5cm deep cut. Bill has recently demonstrated the differences that slashing can make). They had more obvious and more vertical spring. The two higher hydration loaves were flatter in profile.

There was also a more open crumb to the loaves the higher the proportion of water in the dough.

Interestingly the loaves this week had the best blistering of their crust that I have generated to date (see loaf 3 above). This was most evident in loaves 3 and 4. (I didn’t spray the loaves. They were loaded onto the stone, and a glass of cold water was chucked onto a hot oven tray below them just before closing the door.)

So what hydration should you use? Carol Field quotes an Italian baker who boldy stated ‘the wetter the dough the better the bread’ (I am paraphrasing). There are advantages and disadvantages of increasing the proportion of water in a dough. The dough becomes harder to handle and the shape of the resulting loaf is often harder to control, however the crumb does seem to be more open. I haven’t looked at a wide range of hydrations here - the range that I have covered are already at the ‘moist’ end of the spectrum. It would be interesting to look at doughs with 50%, 60% or 80% hydration. Another day perhaps…

### 10 Responses to “Sourdough experiment #3 170606 Hydration”

1. TP Says:

Dom, yes, the results are quite clear. To me, your wettest loaf is still keeping its shape very well. All of them have good spring. Indeed, you’re an expert in working with wet doughs, like Bill said.

Can’t wait to see a wider spectrum test.

2. sourdom Says:

Thanks TP. That was a speedy reply!

I am not sure what this weekend’s experiment will be, but I will come back to hydration at some point (hopefully).

cheers
Dom

3. Mick Says:

Dear Dom,

The photos of the 66% crumb and the 69% crumb are identical.

Very useful experiment.

Mick

4. Bill44 Says:

Good experiment Dom, clearly supports the theory of wet doughs providing larger holes.
regards
Bill

5. Bill44 Says:

I’ve posted on the forum as well because I wanted use a couple of pics to show something else.
For a given recipe, higher hydration will usually produce larger holes, but also the recipe and the techniques used can have a large influence on the crumb structure. This is taking nothing away from Dom’s experiment.
regards
Bill

6. sourdom Says:

Mick - thanks for pointing that out. (I knew there was a reason those two loaves looked similar…)

Bill - point well taken.
My results with your recipe gave quite a different loaf texture (albeit with the Wholegrain milling flour which I demonstrated last week doesn’t give as good results). (Just imagine what your loaf would be like at 76%!!)

cheers
Dom

7. Bill44 Says:

Dom, I use the traditional hand knead method up to about 65% hyd, any higher than that I use Dan’s method, but with a tiny amount of flour rather than oil. That’s when you appreciate the value of a bench knife (scraper to some). I have managed to handle up to 83% hyd with this method, a sharp learning curve at this hydration, believe me
regards
Bill

8. sourdough explorer » Blog Archive » sourdough experiment #4 250606 To knead or not to knead Says:

[…] sourdough explorer travels in home baking « Sourdough experiment #3 170606 Hydration […]

9. Isabelle Says:

Dear Dom,

Thanks for your experiments, however I am very new to sourdough bread making and am using a starter given to me with a no - knead recipe. This starter and recipe was handed to me by a FREE BREAD INITIATIVE - ‘Love Heart Bakery ‘- a truly generous and anonymous bread maker in Alice Springs, NT, Australia.
I am making 2 rye loaves a week and have been having lots of luck until I got a new oven recently. The old one had no temperature gauge! and the loaves were tasty with a ciabatta like texture and even if a little undersized they were always gobbled up! Now the loaves seem to be rising too fast, I think, having almost as much airspace beneath the lovely crust as bread below! I put a stone in the bottom of the oven and sprinkle it with water after 20 minutes of baking. I am determined to succeed in the no-knead way. Can you give me some tips please???

The night before…
200ml starter
500ml flour
700ml water
mix together and cover away from drafts. Feed stater at this time with 200ml rye flour and enough water to make a thick batter.

The next morning…
Great spongy, gloopy stretchy consistency.
2 teaspoons salt
(herbs/seeds, if you want)

Stir around: should be very wet dough (you couldn’t knead it)…elasticy, stretchy. Add more water if needeed and lump into (2 or 3) well oiled and floured baking tins ; cover and let stand.
Needs to double in size… depending on temp. can take 1.5 - 8hrs.

Bake…
Pre-heat oven to 230 celcius
Gently place tins in oven and DO NOT DISTURB for at least 15 mins.
Rotate at 20 mins if you have to.
At 30 mins, pop out of the oven and put them straight on the racks to finish off another 10mins.
Total time: 40 mins. Loaves should sound hollow when tapped on the bottom. Place on cooling rack for 1 hr, then enjoy,

Isabelle.

10. sourdom Says:

Isabelle,

I have posted your question on the forum, as there are others who have more experience with rye sourdough than I.
Go to http://www.sourdough.com.au/phpBB/viewtopic.php?p=1865#1865

cheers
Dom