September 10, 2020 - 4:51pm
Hydration - Bread Dough
Please help me out..wondering what the hydration is on this bread.not much water but boiled potato and potatoes
in general are pretty wet. Here is the recipe
20 oz boiled potatoes
2 tsp salt
1 1/2 tsp yeast
2 TBL olive oil
16 oz flour
4 oz potato water
Thanks in advance
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Is it because no one knows
People care, but it’s a hard question, because 1) different potato types have different amounts of starch/fiber/water and 2) cooking changes the water fraction.
the internet says that raw potatoes are typically 80% water. So, a guess for ‘effective hydration’ of the recipe is
(4 oz water + 20*0.8 oz water in potatoes)/(16 oz flour + 20*0.2 oz potato starch) = 16/16 ➔>100% hydration. So a very floppy dough.
But it may be much drier if, for instance the potatoes lost water upon cooking. What if they lost half their water? Then the cooked potato would only be 66% water, and effect hydration = (4+20*.66)/(16+20*.33)=75% a drier dough.
See why there were no replies? You’ll just have to try it out and report back.
i will say, that I’ve never made bread that had such a large amount of non-flour, though. This will have very little gluten, and be a dense bread, whatever the hydration. Are you sure 20 oz of potato isn’t a typo?
I'll go out on a limb and say the recipe in the OP won't make bread. Potatoes at around 1/4 of the weight of the flour will make a nice robust loaf, tending to denseness, and you can push it a bit higher, but the posted recipe will be a mess.
Potato bread recipes are notoriously imprecise (I see on on the 'net that just specifies "one potato"!) and yes, the variety of potato and how much water drains/steams off after cooking makes a huge difference. You always have to build in a hydration-correction step if you are using fresh potatoes. I've gone to using potato flour, because it's fewer steps and I get consistent results.
Colin2, is potato starch the same as potato flour, or somewhat different?
Lance
Potato flour is made from whole peeled potatoes, cooked, dried, and ground into a fine, beige-colored powder. Potato starch is “washed” out of crushed potatoes, then dried to a fine, bright-white powder. ... Potato flour includes fiber, protein, and flavor, while potato starch is pure flavorless starch. Bobs Red Mill makes a good potato flour
With some additional flour and makes a bread similar to a ciabatta.
Those were basically the same numbers I came up with just curious as to whether my thinking was correct .