Maths is fun! (if you want to cook)

I alluded to this post in my last blog, and here it is.  Maths!  Think about when you were back in school thinking "When am I ever going to need to know this stuff? I only want to cook stuff in a kitchen when I work!"

WELL...

Have you ever found a really good looking recipe in a book or on the internet that serves 8 people and uses measurements such as cups and spoons?  What if you have 23 people to feed?  There is no easy way of  measuring 3 and 7/8's cups of flour.  And what if your cup of flour is more or less heaped than the person who wrote the recipe?

Enter the maths.  Every baker has to have a fair understanding of percentages to make bread and cake.  Take the recipe I posted for the Pumpkin bread:

Flour 80%

Wholemeal Flour 20%
Pumpkin 35%
Salt 2.4%
Yeast 0.4%
Water 45%
Starter 30%

With this recipe, I can make a small dough for one loaf, or I can make 100 loaves simply by expanding the percentages out to the number I need.

The only thing you have to remember is that all the percentages are worked off the flour weight.  You will notice that the wholemeal flour + normal flour = 100%.

So if you make a dough that needs 1 Kg flour, for this recipe you need to have 800g white flour and 200g wholemeal flour.

Once we know that we need 1Kg of flour, we can easily work out how much of the other ingredient we need.  For example, 35% pumpkin is 350g, 2.4% salt is 24g etc.

Too easy right?  Well what if I want to make a pumpkin bread with 36kg flour?  (You might need a calculator for this one!)  Just find out what 35% of 36kg is... (12.6kg if you were wondering) and continue with the rest of the ingredients.  Voila! You have now upscaled the recipe from one loaf of bread to eighty!

It really is easy to do, and I dont understand why everyone doesnt write recipes like this.  There is a whole lot more maths behind the scenes like figuring out how much flour you need to be able to make 14 loaves or serves of the product, but we wont go there....

So just remember, next time you come up with a recipe, use weight measurements (because they are universal)  and express the recipe in percentages.  When you come back to make it again, you can expand or contract the recipe accurately to suit how many people you are catering for.

Because I have gone a whole post without a picture, I thought I would add this picture to lighten the mood... Enjoy the cat!