After you have your item list broken down into purchase units (e.g. case) and inventory units (e.g. #10 can), you can begin to visualize the production process. For each ingredient, make a list of units commonly called in recipes. This will vary depending on how many different recipes use each item.
Three common portion methods for recipe ingredients are weight, volume and count. Meat items are often portioned by weight and count. When portioning by the piece, you may have more than one portion size. A strip steak could be sold in two or three portion sizes. For each portion size, imagine the entire strip will be used. You need to answer a simple question. How many steaks would you expect if you only cut the one size from the strip? Repeat the exercise for each portion size.
Use the average weight for popular random weight items. Generally, each case will always have the same number of large cuts (ribs, strips, loins, etc.). The total case weight will vary. Huge weight variances from the average will impact the number of portions per piece. It helps to keep accurate records of the butchering and fabrication process.
Yields may change from week to week. If you expected a 80% yield for a particular cut and you actually hit a 70% figure, your costs would run higher by over 11%. The variance is due to the poor yield alone. Add a price variance and some spoilage and the gross margin will begin to disappear. Portion control steaks provide operators with a consistent yield - one portion. When deciding to purchase portion control meat, you need to consider the hidden costs. Look at the whole picture including labor, equipment, risk of injury, and poor yield in your comparison.
Items portioned by volume or weight are straight forward. It is helpful to know the common conversion units for each method. Volume is expressed in gallons, quarts, pints, cups, liters, fluid ounces, milliliters, shots, tablespoons, teaspoons and fractions of each. Weight may be expressed in pounds, ounces, kilograms, grams, etc. A #10 can has about 6 pints (96 fluid ounces) and often about 6 pounds. Check all weight to volume relationships.
When developing standards, you may find your specifications are different than some of the excellent books. If you trim your produce quickly, the yield will probably be lower than the expectation. One way to reduce the variance is to portion produce items by the piece. A 24 head case of iceberg lettuce will yield 144 wedges if sliced in six pieces per head. Cutting the heads into larger wedges of four per head would yield only 96 portions.
Think of this step as the recipe model equivalent of the prep process. Having accurate recipe costs depends on accurate unit and yield data. The recipe costing programs will re-cost your recipes over and over as prices change. Spend the time initially to get this critical information correct for your operation. Don't worry about benchmarks for portion size. Use your unique portion sizes in determining the conversions between inventory count units and the units called for in recipes.
