Scaling a recipe means that you are adjusting the ingredient quantities for a different amount of servings. While doubling or halving a recipe is relatively easy, you will need to do some math when you want to convert a six-serving recipe for two people or 14 people. Whether you're increasing a recipe or decreasing it—the procedure for adjusting the ingredient quantities is the same.
The first step is to determine a conversion factor. Next, you need to multiply this number by the ingredient measurements. If this number is an odd amount for that particular measurement, you will then need to convert to a different type of measurement. This may sound like a lot of work, but you won't need to convert every ingredient in a recipe into another form of measurement. And with these formulas, you are sure to have your recipe turn out perfectly.
\[Recipe\, Conversion\, Factor \, (RCF)= \frac{New\, Recipe\, Servings}{Original\, Recipe\, Servings} \]
Be careful not to round the factor and flip the fraction in the formula. The factor also has no unit.
Example: Your original recipe makes 10 portions. You want to convert the recipe to serve 215 people. Calculate the RCF and determine how much of the following you should order?
Solution:
Calculate Recipe Conversion Factor:
\[RCF = \frac{New\, Servings}{Old\, Servings} =\frac{215}{10}=21.5\]
Red Bell Peppers
\[2lbs. \times 21.5 = 43 lbs.\]
Calculate the APQ:
\[APQ = \frac{43lbs}{0.93} = 46.23655914lbs\]
Cilantro
\[1\,bunch \times 21.5 = 21.5\, bunches\]
\[APQ = \frac{21.5\, bunches}{1} = 21.5\, bunches\]
Garlic
\[1 \, T \times 21.5 = 21.5\, T\]
\[APQ = \frac{21.5\, T}{0.87} = 24.71264368\, T\]