Bakers math

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Peternumnums on 14 May 2023 at 17:33

Hello 

I am trying to figure out the steps I need to take to answer this question and I'm having a tough time with it. 

If I have 100 grams of starter and I know it is an 80% hydration starter, how do I determine how much flour is in the starter?

I actually know the answer (54g flour 44g water), I just dont know how to arrive at it for myself. 

 

I am looking for the steps to take so I can do it for myself.  

If anyone knows how to arrive at the answer it would be much appreciated. 

Many thanks

Peter

The desired weight is 100-gram

Assume % flour is 100%

Water  % is 80

Total % is 180

Conversion factor is 100 / 180 = 0.555556 (weight / total percent)

Multiply each of the ingredients % by conversion factor.

Flour = 100 * 0.555556 = 55.5556 gram

Water  =  80 * 0.555556 = 44.4444 gram

Round off the results.

Cheers,

Gavin

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Yippee on 14 May 2023 at 22:31

 

The long way:

Let the weight of flour in your starter be 1x.

Then the weight of water in your starter is 0.8x.

We can set up the equation: 1x + 0.8x = 100.

Combining like terms, we have: 1.8x = 100.

To solve for x, we divide both sides of the equation by 1.8:

x = 100/1.8.

Therefore, x ≈ 55, which represents the weight of flour in your starter.

 

The shortcut:

Alternatively, you can use the following formula: 

 

divide the weight of the starter 

by

(1 + the ratio of water to flour in the starter, i.e., the starter hydration)

 

👇👇👇

100/(1+0.8) = 55

 

Yippee 

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Abe on 15 May 2023 at 04:24

80% hydration can also be expressed as 4:5 (4 parts water to 5 parts flour by weight). 

4 + 5 = 9

100 [starter] / 9 = 11.1111 (go to 4 decimal places)

Then multiply each part of the ratio by 11.1111....

4 [water] x 11.1111 = 44.4444

5 [flour] x 11.1111 = 55.5555

So the answer would be 44.4g water + 55.5g flour to be exact but round up or down to the nearest whole number.