## Rocedure for Changing Portion Sizes

If your recipe yields, let's say, 20 portions, 4 ounces each, and you need 30 portions, 5 ounces each, you must add a few extra steps to the conversion process.

1. Determine total yield of the recipe by multiplying the number of portions by the portion size:

portions x portion size = total yield (old)

2. Determine the total yield you desire by multiplying the desired number of portions by the desired portion size:

desired portions x desired portion size = total yield (new)

3. Divide desired yield by recipe yield to get the conversion factor:

total yield (new)

-= conversion factor total yield (old)

4. Multiply each ingredient by the conversion factor:

conversion factor x old quantity = new quantity

Note: The conversion factor may sometimes turn out to be 1. In these cases, the total yield is obviously the same, and the recipe does not need to be changed.

the principle is exactly the same:You multiply each ingredient by a number called a conversion factor, as on the previous page.

In order to make these procedures clearer, let's work through the conversion of a full recipe to give you practice with the equations.The following examples are in the U.S. system of measures. For metric examples, see Appendix 4,page 1028.

In the first column that follows is a list of ingredients for a sautéed beef dish. As you can see, the quantities given in the second column are enough to make eight portions at 8 ounces each.

Beef tenderloin tips and mushrooms à la crème Portions: 8 Portion size:8 oz

 Butter 2 oz Onions 4 oz Flour 1 tbsp Mushrooms 12 lb Beef tenderloin 212 lb White wine V2 cup Prepared mustard 2 tsp Brown sauce 112 pt Heavy cream 1 cup Salt to taste Pepper to taste Let's say we need 18 portions instead of 8.To find the conversion factor,we divide

the new yield by the old yield:

the new yield by the old yield:

To convert the recipe to 18 portions, we simply multiply each ingredient quantity by this conversion factor of 2.25.

First, to make this easier, we should change pounds to ounces and cups, pints, and quarts to fluid ounces, using the figures in Table 5.2. For example, to change the measurement for beef tenderloin to ounces,multiply 2V2 (the weight in pounds) by 16 (the number of ounces in a pound) to get 40 ounces.

The equivalents we need for this recipe are as follows:

V2 lb equals 8 ounces 2//2 pounds equals 40 ounces 3/2 cup equals 4 fluid ounces IV2 pints equals 24 fluid ounces

In Example 1,page 105, we have substituted these equivalent quantities.Then we have multiplied all the ingredient quantities by the conversion factor to get the quantities that we need for 18 portions. Check through all the calculations to make sure you follow them.The quantities for salt and pepper will still, of course,be indicated as "to taste."

Now let's suppose we want to find the quantities needed to give us 40 portions, 6 ounces each. Because the portion size changes, we must use the second procedure explained previously. First, to find the total yield of the old recipe,we multiply the number of portions by the portion size:

Do the same calculation for the desired yield:

When we divide the new yield by the old yield (240 divided by 64), we arrive at a conversion factor of 3.75. In Example 2,we have done the conversions using the new factor of 375.

 Example 1 Ingredient Quantity Times Conversion Factor Equals New Quantity Butter 2 oz x 2.25 = 4.5 oz Onions 4 oz x 2.25 = 9 oz Flour 1 tbsp x 2.25 = 2.25 tbsp or 2 tbsp plus % tsp Mushrooms 8 oz x 2.25 = 18 oz or 1 lb 2 oz Beef tenderloin 40 oz x 2.25 = 90 oz or 5 lb 10 oz White wine 4 fl oz x 2.25 = 9 fl. oz Prepared mustard 2 tsp x 2.25 = 41/2 tsp or 11/2 tbsp Brown sauce 24 fl oz x 2.25 = 54 fl oz or 3 pt plus 6 fl oz Heavy cream 8 fl oz x 2.25 = 18 fl oz or 2/4 cups Example 2 Ingredient Quantity Times Conversion Factor Equals New Quantity Butter 2 oz x 3.75 = 7.5 oz Onions 4 oz x 3.75 = 15 oz Flour 1 tbsp x 3.75 = 3 75 tbsp or 3 tbsp plus 2/4 tsp Mushrooms 8 oz x 3.75 = 30 oz or 1 lb 14 oz Beef tenderloin 40 oz x 3.75 = 150 oz or 9 lb 6 oz White wine 4 fl oz x 3.75 = 15 fl. oz Prepared mustard 2 tsp x 3.75 = 71/2 tsp or 21/2 tbsp Brown sauce 24 fl oz x 3.75 = 90 fl oz or 5 pt plus 10 fl oz Heavy cream 8 fl oz x 3.75 = 30 fl oz or 3% cups PROBLEMS IN CONVERTING RECIPES

For the most part, these conversion procedures work well. But when you make some very large conversions—from 10 to 400 portions, for example, or from 500 to 6—you may encounter problems.

For example,you may have to make major equipment changes, like from a 2-quart saucepot to a large steam kettle. Consequently, you have to adjust your techniques and, sometimes, even ingredients. Evaporation rates may be different, thickening agents may need increasing or decreasing, seasonings and spices may have to be cut back. Or sometimes quantities may be too large or too small to mix properly.

This is one more example of the importance of cooking with judgment. Experienced chefs develop a feel for these problems over the years.When you make such adjustments on converted recipes, be sure to make a note of them for future reference.

Although there are no fixed rules you can learn for these adjustments, it is possible to list the most common types of problems encountered so that you can be on the alert for them when making recipe conversions. In general,most of the pitfalls fall into one of the following categories.