You would want to do this if you were making a recipe or converting a recipe. Like....https://www.instructables.com/id/Metrication-of-Recipes-Simplified/
Step 1: Go to USDA Database
and type in the item in the keyword box and choose what food group it is in.
Keyword - Carrot
Food Group - Vegetables and Veg Products
Step 2: Choose From List
For this Example... for carrot there are 19 choices, today we will stick to Carrots, raw. Now hit submit at the bottom.
Step 3: Choose the Cup Amount
For this Example of Carrots, Raw - there are three cups to choose from
- 1 cup chopped 128 g
- 1 cup grated 110 g
- 1 cup strips or slices 122 g
These are America cups so they have a value of 237 mL
and we are after the weights of the cups in grams.
Step 4: Find Density of Food
Density = weight/volume
For this Example of Carrots, Raw...
1 cup chopped 128/237 = .54 g/mL
1 cup grated 110/237 = .464 g/mL
1 cup strips or slices 122/237 = .515 g/mL
If you select one of the amounts and submit it on the next page you will get the Nutrition value, but we are only after the density value, our job is done with the USDA site.
Step 5: Use Density Value in Calculator
For this Example...
I want the weight of two Metric cups of chopped or sliced carrots. Metric Cup = 250 mL
Input .54 into the Density box,
Input 500 into the 'Convert what quantity?' box,
Choose milliliter in the 'From this' List, and choose grams in the 'To this' list,
You will get the Results of 500 milliliter = 270 grams
Now you will have 270 g of sliced carrots instead of 2 cups of carrots
You can now weigh out the amount of carrots you need before you clean or chop them up for your recipe.