Now You're Cooking! Tip

September-December 2012

Recipe Ingredient and Unit Descriptions for Nutritional Analysis

NYC users are often confused by nutrition analysis results that vary depending on how a recipe ingredient and its unit are described.

Here is an example ingredient from a user’s recipe: "1 cup Cheddar cheese; shredded".

If you just use "cup" as the unit, then the nutrition analysis for this ingredient shows 953.47 calories.

If you use a mass-qualified unit such as "cup (132 g)" (using the weight shown in the nutrition item’s conversion list for 1 cup of diced cheddar), the nutrition analysis gives 531.96 calories.

If you use "cup, shredded" for the units (to match one of the nutrition database conversions for cheddar cheese), you get 455.39 calories which matches what the database shows.

Thus, we have three different nutritional analyses that might be confusing if you don’t know what NYC is doing.

This is a good example as shredded cheese is much less dense than unshredded, so you can get widely varying answers depending on the descriptions you use.

First a little background…

NYC considers ONLY your recipe ingredient description and NOT your ingredient preparation . Also, NYC does nutritional analysis using mass, not volume, so if you use a mass unit, NYC can convert easily to grams. Also, if you do not use a “mass” unit (e.g., oz, lb, kg, g, mg), then NYC must estimate mass from your volume unit (e.g., cup, tsp, tablespoon). If you use a volume unit (1 cup), NYC tries hard to find a unit conversion by looking 1) in the units list for the USDA food item, then 2) in your Shopping… Conversions… list. The key to accuracy is always use mass units like oz, lb, kg, g, mg or mass-qualified units like “1 cup (200 g)” --- because there is no need for any assumptions by NYC when you do this.

Taking the example ("1 cup cheddar cheese" with preparation "shredded"), NYC only sees “cheddar cheese” in the ingredient description, not the “shredded” in the preparation. And it sees “1 cup” with no mass qualifier. Finding no exact match in the USDA units list for converting "1 cup" to a mass unit, NYC converts 1 cup using whatever mass conversion you have for 1 cup in your units conversion list in Shopping... Conversions... (most folks have the weight of 1 cup water here). My conversion list shows 238.6 g for 1 cup (which is the weight of 1 cup water), which would produce 961 calories for 1 cup (238.6 g) of cheese. But this would be for 1 cup of unshredded cheese with an assumed density equal to that of water. Not what you are really after !

So if we use the mass-qualified unit of “1 cup (132 g)” which gives him 132 g of cheese which has 531.9 calories. This is correct for diced cheese, as “132 g” is the mass given in the nutrition database conversion list for “1 cup, diced”.

But if we use “1 cup, shredded” as the unit, NYC sees an exact match to one of the conversions for the USDA nutrition item, where “1 cup, shredded” has 113 g or (113/132) x 531.9 = 455.3 calories.

So does 1 cup shredded cheddar weigh 238.6 g (like a cup of water), or 132 g (like your mass-qualified unit for diced cheddar), or 113 g (like the USDA item’s conversion unit). As NYC user, the more specific you describe each ingredient and unit, the better the nutrition analysis . Obviously, inserting a mass-qualified unit "1 cup (132 g)" gives you direct control over what NYC assumes for the nutrition analysis, so we always recommend this.

The NYC user has responsibility for ensuring accurate nutrition analysis by using “proper” ingredient descriptions and units with a knowledge of how NYC works. NYC simply cannot be programmed to understand every possible permutation of ingredient descriptions and units text in the human mind for every single food item. For example, “shredded cheddar” vs “shredded cheddar cheese” vs “cheddar, shredded” vs “cheddar cheese, shredded” vs “diced cheddar” vs “cheddar, diced” vs “cheddar diced” etc etc. So NYC just does the best it can with what you give it.

There is no substitute for 1) familiarity with the USDA database, and 2) knowing how NYC works.

However, if you consistently use mass units (e.g., oz, lb, kg, g, mg) or mass-qualified units like "1 cup (200 g)” in recipes for which you need nutritional analysis, you will be fine because this gives you direct control of the conversion that NYC uses.

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