Chef Burton -
This seems like something right up your alley....
I've always wanted to know how to properly scale a recipe without depending on an automated scaling application just to understand how it works. And, there are times when I need to do it manually without technology. It seems to be one of those topics that's not discussed much. No doubt, it can be intimidating.
I am including what I have used in the past a few times, which I found online, but it seems a bit "clunky". I think working in all metric makes this particular set of instructions, and measuring in general, much easier. However, perhaps there's an alternate way? I'm also including a very simple recipe in all metric to use as a sample recipe for discussion purposes.
Thanks for any useful information anyone can provide.
Scaling Method I've Used
First, calculate your conversion factor, which is a number you're going to use to convert all the quantities.
To find your conversion factor, simply divide the desired number of servings by the original number of servings. The resulting number is your conversion factor. Here's the formula:
desired servings / original servings = conversion factor
Therefore, scaling a 10-portion recipe down to six portions involves two steps:
1) Divide 6 by 10, which gives you a conversion factor of 0.6.
2) Multiply each ingredient amount by 0.6.
For example, say your recipe calls for 2 quarts of chicken stock. All you need to do is multiply 2 quarts by your conversion factor of 0.6:
2 quarts × 0.6 = 1.2 quarts chicken stock
What exactly is 1.2 quarts? Well, questions like that are why most of the world uses the metric system. The rest of us are going to have to convert 1.2 quarts into ounces. Using a conversion tool, there are 32 oz in a quart. There are 32 ounces in a quart, so:
32 × 1.2 = 38.4 ounces
We can round that down to about 38 ounces, or 4 3/4 cups.
Sample Recipe to Scale
Basil Panna Cotta
This yields 10 servings. For discussion purposes, I want to scale it for 6 servings.
1000 g heavy cream
7200 g granulated sugar
60 g basil
20 g spinach
6 sheets gelatin, bloomed
1. Warm cream with sugar. Add basil and spinach. Add bloomed gelatin and blend. Strain.
2. Pour into molds and let set in refrigerator.
