Exam Notes: Recipe Scaling, Percent Yield, Volume/Mass Conversions

Recipe Scaling, Percent Yield, Volume/Mass Conversions

This note covers recipe scaling, percent yield calculations (APQ vs. EPQ), and volume-to-mass conversions relevant to food management, particularly in the context of using "Food for Fifty" (FFF) tables.

Importance

  • 33% of the RD (Registered Dietitian) board exam covers food management. Pay close attention!

Today's Flow

  • Define, Example, Practice
    • Scaling
    • % Yield
    • Costing
  • FFF 4.1 (Scaling), FFF 4.3 (% Yield), FFF 4.2 (Volume/Mass)

Key Concepts

  • As Purchased Quantity (APQ) vs Edible Portion Quantity (EPQ)
  • Increase/decrease yield to feed everyone without wasting food or money.
  • Scaling.
  • Costing.
  • Percent Yield.

Scaling

  • Increase/decrease recipe yield to feed the required number of people, optimizing cost and minimizing waste.
  • Refer to Food for Fifty table 4.1.

Scaling Example 1: Conversion Factor

  • Original recipe yields 100 portions.
  • Catering event for 50 guests.
  • What is the conversion factor?
  • Formula: Portions Needed / Original Portions = Conversion Factor
    Conversion\,Factor = \frac{Portions\,Needed}{Original\,Portions}
  • Calculation: 50 portions / 100 portions = 0.5
  • Conversion Factor (CF) = 0.5

Scaling Example 2: Converting Recipes

  • Original recipe calls for 1/2 cup of sugar.
  • Conversion factor is 10.
  • How much sugar does the converted recipe require?
  • Formula: Original Quantity X Conversion Factor = New Quantity
    New\,Quantity = Original\,Quantity \times Conversion\,Factor
  • Calculation: 1/2 cup X 10 = 5 cups
  • New Quantity = 5 cups

Scaling Example 3: Application

  • Original recipe for 12 deviled eggs calls for 1 tsp dijon mustard.
  • Need to serve 144 people.
  • How much dijon does the converted recipe require?
  • Step 1: Calculate Conversion Factor
    CF = \frac{144\,portions}{12\,portions} = 12
  • Step 2: Calculate the amount of dijon mustard needed
    1\,tsp \times 12 = 12\,tsp
  • Step 3: Convert to common measurement

Scaling Example 4: Common Measurement

  • Always use the largest possible measurement.
  • Conversion: 1 cup = 48 tsp
  • Calculation:
    \frac{12\,tsp}{48\,tsp/cup} = \frac{1}{4}\,cup
  • Final Recipe: 1/4 cup of dijon mustard is required.

Scaling: Practice Problem

  • Original recipe for 1 chocolate cake calls for 2 cups AP flour.
  • Cake serves 12 people.
  • Need to serve 60 people.
  • How much flour is required? (Final answer in quarts).

Scaling Solution: Application

  • Step 1: Calculate Conversion Factor
    CF = \frac{60\,portions}{12\,portions} = 5
  • Step 2: Calculate the amount of flour needed
    2\,cups \times 5 = 10\,cups
  • Step 3: Convert to common measurement

Scaling Solution: Common Measurement

  • Always use the largest possible measurement.
  • Conversion: 1 quart = 4 cups
  • Calculation:
    \frac{10\,cups}{4\,cups/quart} = 2\,quarts\,and\,2\,cups
  • Final Recipe: 2 quarts and 2 cups of AP flour.

Percent Yield

  • Relates As Purchased Quantity (APQ) to Edible Portion Quantity (EPQ).
  • Compares purchased quantity to edible quantity after processing.
  • Refer to Food for Fifty table 4.3.

Percent Yield Example:

  • Flat of carrots weighs 15 lbs (APQ).
  • After cleaning and cutting, 12.75 lbs remain (EPQ).
  • What is the percentage of edible portion?
  • Formula:
    Yield\,\% = \frac{EPQ}{APQ} \times 100
  • Calculation:
    Yield\,\% = \frac{12.75\,lbs}{15\,lbs} \times 100 = 85\%
  • Yield = 85%

Percent Yield: Practice Problem

  • Box contains 8 pineapples.
  • Each pineapple weighs about 4 lbs.
  • After peeling & trimming, 16 lbs & 10 oz of chunks remain.
  • Determine the percent yield.

Percent Yield Solution: Conversions First

  • Convert all measurements to the same unit (ounces).
  • Conversion: 1 lb = 16 oz
  • Calculations:
    • APQ = 32 lbs
      APQ = 32\,lbs \times 16\,oz/lb = 512\,oz
    • EPQ = 16 lbs and 10 oz
      EPQ = (16\,lbs \times 16\,oz/lb) + 10\,oz = 266\,oz

Percent Yield Solution: % Yield

  • Yield\,\% = \frac{EPQ}{APQ} \times 100
  • Yield\,\% = \frac{266\,oz}{512\,oz} \times 100 = 52\%
  • Yield = 52%

Volume à Mass

  • Recipes use volume.
  • Ordering uses mass.
  • Food for Fifty table 4.2.

Volume → Mass Example

  • Sacred Heart Hospital’s overnight oats recipe calls for 2 quarts of oats.
  • What is the mass of oats needed?
  • Conversion: 1 lb = 5\frac{1}{3} cups ($\approx 5.33$ cups)
  • Conversion: 2 quarts = 8 cups
  • Calculation:
    8\,cups \times (\frac{1\,lb}{5\frac{1}{3}\,cups}) = \frac{8}{5\frac{1}{3}}\,lbs \approx 1.5\,lbs
  • The recipe calls for 1.5 lbs of oats.

Closing Thoughts

  • Defined: Scaling, % Yield.
  • Scaling: Using conversion factors to scale recipes.
  • % Yield: How much to order versus how much you'll have after preparation.
  • Volume to Mass Conversions: Converting from recipes to ordering.