An amino acid table looks like reference data and is usually filed without being read. That is a mistake, because for a plant protein the table is the most useful commercial document you receive: it tells you whether the protein claim is internally consistent, which amino acid limits the protein quality, and therefore which other ingredients will raise the value of your formulation. This article works through the pea protein profile we publish, the three calculations that matter, and how to use them to build a blend rather than guess at one.
The full profile is on the Pea Protein 80% product page; the broader technical treatment is in Pea Protein 80%: Composition, Functionality and Selection.
1. The profile, and the first check
| Amino acid | g/100 g product | Amino acid | g/100 g product |
|---|---|---|---|
| Aspartic acid | 9.11 | Isoleucine | 4.12 |
| Threonine | 2.90 | Leucine | 7.07 |
| Serine | 3.93 | Tyrosine | 3.16 |
| Glutamic acid | 14.21 | Phenylalanine | 4.55 |
| Proline | 3.92 | Histidine | 1.99 |
| Glycine | 3.20 | Tryptophan | 0.81 |
| Alanine | 3.39 | Lysine | 5.94 |
| Valine | 4.25 | Arginine | 6.94 |
| Cystine | 0.82 | Total | 81.35 |
| Methionine | 1.04 | – | – |
Check one: does the sum support the protein claim? The total is 81.35 g per 100 g of product against a declared crude protein of 80% minimum. Those two numbers agreeing to within a couple of percent is what a correct analysis looks like, because the summed amino acids and the nitrogen-based crude protein should converge for a protein that has little non-protein nitrogen.
If a certificate shows a total amino acid sum well below the declared crude protein – say 70 g against a claimed 80% – one of three things has happened: the protein figure is inflated, the amino acid analysis is incomplete (tryptophan is often omitted because it needs a separate hydrolysis), or the material contains a significant non-protein nitrogen fraction. Any of the three is a reason to ask for the raw data.
2. Convert to “per 100 g of protein” before comparing
Reference amino acid patterns are expressed per 100 g of protein, not per 100 g of product. The conversion uses the summed amino acid content as the denominator, which gives a slightly stricter answer than dividing by the crude protein:
| Amino acid | g/100 g product | g/100 g protein (divide by 81.35) | Reference for young children | Verdict |
|---|---|---|---|---|
| Lysine | 5.94 | 7.3 | about 5.7 | above requirement – the strength |
| Methionine + cystine | 1.04 + 0.82 = 1.86 | 2.3 | about 2.7 | below requirement – the limitation |
| Threonine | 2.90 | 3.6 | about 3.5 | marginal |
| Tryptophan | 0.81 | 1.0 | about 0.9 | adequate |
| Leucine | 7.07 | 8.7 | about 6.6 | well above |
| Valine | 4.25 | 5.2 | about 5.0 | adequate |
Two conclusions fall out of that table and they are the whole reason pea protein is blended rather than used alone in bakery and cereal products:
- Sulphur amino acids are limiting. At 2.3 g per 100 g of protein against a 2.7 reference, pea protein cannot be the sole protein in a product aimed at young children without either a higher inclusion or a complementary source.
- Lysine is comfortably above requirement. At 7.3 against 5.7, pea protein supplies exactly what cereal proteins lack.
3. Why the pea-cereal pairing works
| Protein source | Lysine (g/100 g protein) | Sulphur amino acids (g/100 g protein) | Role in the blend |
|---|---|---|---|
| Pea protein | about 7.3 | about 2.3 | supplies lysine |
| Wheat protein | about 2.5 – 3.5 | adequate to high | supplies sulphur amino acids |
| Rice protein | about 3.5 – 4.0 | adequate | supplies sulphur amino acids, neutral flavour |
| Maize protein | about 2.5 – 3.0 | adequate | supplies sulphur amino acids |
The complementarity is quantitative, not rhetorical: each source’s surplus covers the other’s deficit. A blend of pea and wheat at roughly the ratio in which they already appear in a pasta or a biscuit formulation is usually better balanced than either alone, which is a useful answer when a customer asks why the product contains two proteins.
4. Building a blend: a worked example
Take a snack product that should supply about 12 g of protein per 100 g, with pea protein and wheat flour as the protein sources.
| Component | Inclusion per 100 g | Protein supplied | Lysine supplied |
|---|---|---|---|
| Wheat flour (about 11% protein) | 70 g | 7.7 g | about 0.23 g |
| Pea protein 80% (72% as-is) | 6 g | 4.3 g | about 0.26 g |
| Total | – | 12.0 g | about 0.49 g |
| Lysine per 100 g protein in the blend | – | – | about 4.1 g |
Now the useful part: the blend sits at 4.1 g of lysine per 100 g of protein, still below the 5.7 reference, because wheat dominates the protein. Raising the pea inclusion to 12 g takes the total protein to about 16.3 g and the lysine to about 5.1 g per 100 g of protein – closer to requirement but still short, and now over the protein target. In practice the answer is either to accept the blend as part of a mixed diet (which is how most foods are actually eaten) or to add a small quantity of a lysine-rich ingredient, which is exactly the commercial argument for pea protein in the first place.
The exercise is worth running because it converts a vague claim (“plant protein blend”) into a number a customer can check – and because it shows when the blend is doing real work and when it is decoration.
5. Leucine and the sports-nutrition calculation
Sports-nutrition formulators often look at leucine, because it is the amino acid most discussed in muscle protein synthesis research. The profile gives 7.07 g per 100 g of product, which is 8.7 g per 100 g of protein.
| Scenario | Product required | Leucine delivered |
|---|---|---|
| 20 g protein from pea protein | 27.8 g of product (at 72% as-is) | about 2.0 g |
| 25 g protein from pea protein | 34.7 g of product | about 2.5 g |
| Same protein from whey isolate | – | typically higher per gram of protein |
We do not make performance claims, and the clinical threshold discussion is outside the scope of an ingredient article. The point is narrower: pea protein delivers less leucine per gram of protein than dairy protein, so a formulation that relies on a leucine target needs the arithmetic done rather than the protein target assumed.
6. What the profile cannot tell you
- Digestibility. Amino acid composition says nothing about how much of each amino acid is actually absorbed; that is what PDCAAS and DIAAS measure, and both depend on processing history and method.
- Availability of individual amino acids. Lysine can be damaged by heat and by Maillard reactions during drying or baking; a compositional analysis reports what is present, not what is bioavailable.
- Tryptophan accuracy. It is destroyed by standard acid hydrolysis unless a separate alkaline method is used, which is why tryptophan figures are often estimates.
- Flavour. Nothing in the table predicts the beany or green note, which comes from lipid and from volatile compounds.
7. A practical checklist
- Ask for the amino acid certificate per lot if you make any protein quality claim.
- Check that the amino acid sum is consistent with the declared crude protein.
- Convert to g per 100 g of protein before comparing with reference patterns.
- Identify the limiting amino acid and design the blend to cover it.
- Recalculate after any process change that involves heat, because lysine availability is the first thing to suffer.
- If you need a digestibility score, measure it on your own material.
References and scope note
All ratios in this article are calculated from the amino acid profile on the product page, divided by the summed amino acid content of 81.35 g/100 g. Reference pattern values are the conventional FAO/WHO figures for young children, quoted for orientation and not as a regulatory standard. No health, nutrition or therapeutic claims are made for this ingredient.
Technical and commercial orientation only. Not a substitute for nutritional assessment, claim substantiation or regulatory review.
PolyBlueChem supplies pea protein 80% with a lot-specific amino acid certificate. Contact polybluechem@163.com for samples or the analytical package your nutrition team needs.