Protein content
2.1 g of protein in 1 cup (246 g) of liquid whey, or 3.1 g for every 100 kcal it supplies.
Share of this food's calories that come from protein - it is more of an energy food than a protein food.
| Protein per 100 kcal | 3.1 g |
|---|---|
| Protein per 100 g | 0.85 g |
| Protein per serving | 2.1 g in 1 cup (246 g) |
| Calories from protein | 13% |
| Leucine per serving | 0.19 g |
| Rank in dairy foods, per 100 kcal | 74th of 81 |
| Rank of all foods, per 100 g | 747th of 796 |
| Share of 50 g Daily Value | 4% per serving |
| Protein quality | Complete protein |
One 1 cup, 2.1 g protein.
Every 100 kcal of liquid whey brings 3.1 g of protein. On that measure it ranks 74th of the 81 dairy foods in this database and 612th of all 796 foods on the site. Measured by weight instead, its 0.85 g per 100 g ranks 81st in its group.
Around 13% of the calories in liquid whey come from protein, so it is more of an energy food than a protein food. It contributes to a day's protein total, but the bulk of what it delivers is energy rather than amino acids - treat it as a contributor alongside a denser source, not as the protein in a meal.
USDA lists 0.36 g of fat per 100 g of liquid whey, too little for a protein-to-fat ratio to mean much.
Set against neufchatel cheese, another dairy food entry in the database, a serving carries about 0.5 g less protein (neufchatel cheese has 2.6 g per 1 oz).
It is a complete protein - it supplies all nine essential amino acids in adequate amounts, so it can carry a meal's protein on its own. The serving quoted here is measured by volume at 246 g, and it covers about 4% of the 50 g FDA Daily Value for protein.
The watery liquid left after curds are strained off.
Serving sizes
| Portion | Weight | Protein | Calories |
|---|---|---|---|
| 100 g | 100 g | 0.85 g | 27 kcal |
| 1 cup (serving used here) | 246 g | 2.1 g | 66 kcal |
| 1 quart | 984 g | 8.4 g | 266 kcal |
Portion weights are the household measures listed on the USDA record; protein and calories scale from the per-100 g figures.
Amino acids
| Amino acid | Per 100 g | Per serving | mg per g protein |
|---|---|---|---|
| leucine | 0.078 g | 0.19 g | 92 |
| lysine | 0.068 g | 0.17 g | 80 |
| valine | 0.046 g | 0.11 g | 54 |
| isoleucine | 0.047 g | 0.12 g | 55 |
| threonine | 0.054 g | 0.13 g | 64 |
| phenylalanine | 0.027 g | 0.07 g | 32 |
| methionine | 0.016 g | 0.04 g | 19 |
| histidine | 0.016 g | 0.04 g | 19 |
| tryptophan | 0.013 g | 0.03 g | 15 |
Per-100 g values are the amino acid analysis on the USDA record. The serving and per-gram-of-protein columns are arithmetic on those values; they are not a protein quality score.
Related
Highest-protein dairy foods per serving · Most protein-dense foods · Highest protein per 100 g
Quick answers
0.85 g. The 1 cup serving used on this page weighs 246 g and so carries 2.1 g.
3.1 g. That figure divides its 0.85 g of protein per 100 g by its 27 kcal per 100 g, so it does not depend on serving size.
Yes. The protein in liquid whey supplies all nine essential amino acids in adequate amounts, so it can carry a meal's protein on its own.
About 4%. One 1 cup serving has 2.1 g, and the FDA Daily Value for protein is 50 g.
Figures from USDA FoodData Central record #171282 (Whey, sweet, fluid), SR Legacy data. USDA data is in the public domain. Values are the published reference figures for that record, not lab measurements for a specific brand or batch.