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The Ultimate Guide to Recipe Calculation

The Ultimate Guide to Recipe Calculation

The Culinary Institute of America

Converting Portion Sizes

Sometimes it will happen that you also need to modify the portion size of a recipe. For instance, say you have a soup recipe that makes four 8-ounce portions, but you need to make enough to have forty 6-ounce portions. To make the conversion:

1. Determine the total original yield and the total desired yield of the recipe.

Number of portions x Portion size = Total yield Example: 4 × 8 fl oz = 32 fl oz (total original yield) 40 × 6 fl oz = 240 fl oz (total desired yield)

2. Determine the recipe conversion factor and modify the recipe as described above.

Example: 240 fl oz / 32 fl oz = 7.5 (recipe conversion factor)

Confusion often arises between weight and volume measures, when ounces are the unit of measure. It is important to remember that weight is measured in ounces, but volume is measured in fluid ounces. A standard volume measuring cup is equal to 8 fluid ounces, but the contents of the cup may not always weigh 8 ounces. One cup (8 fluid ounces) of cornflakes weighs only 1 ounce, but one cup (8 fluid ounces) of peanut butter weighs 9 ounces. Water is the only substance for which it can be safely assumed that 1 fluid ounce equals 1 ounce. For all other ingredients, when the amount is expressed in ounces, weigh it; when the amount is expressed in fluid ounces, measure it with an accurate liquid (or volume) measuring tool.