Hemp seed protein is a complete plant protein, meaning it provides all nine essential amino acids in adequate proportions. Two storage proteins dominate the profile: edestin, accounting for approximately 65 percent of total protein, and albumin, accounting for most of the balance. Both are water-soluble and well-digested.
Protein quality: the PDCAAS reference
The Protein Digestibility-Corrected Amino Acid Score (PDCAAS) is the standard global method for evaluating protein quality. It combines amino acid composition with measured digestibility. Hemp seed protein scores approximately 0.49 to 0.61 on the PDCAAS scale (published values vary by study), below dairy and egg (1.0) but above most plant proteins that are not enriched or blended.
Hemp protein powders (which concentrate the protein and remove some fibre) typically score higher than raw seed because processing improves digestibility. Blends of hemp with other plant proteins (notably pea protein) can approach the PDCAAS of dairy because their amino acid profiles complement each other.
Edestin specifics
Edestin is the dominant globulin in hemp seed. It is structurally similar to mammalian globulins and is processed by human digestive enzymes efficiently. Edestin contains all essential amino acids in proportions that resemble human plasma proteins. This structural similarity is part of why hemp protein is considered well-tolerated by sensitive digestive systems.
Amino acid breakdown
| Amino acid (per 30 g protein) | Hemp seed | Adult requirement |
|---|---|---|
| Leucine | 1.9 g | 2.7 g (70 kg adult) |
| Lysine | 1.3 g | 2.1 g |
| Methionine + cysteine | 1.1 g | 1.0 g |
| Phenylalanine + tyrosine | 2.3 g | 1.7 g |
| Threonine | 1.2 g | 1.0 g |
| Tryptophan | 0.4 g | 0.3 g |
| Valine | 1.6 g | 1.8 g |
| Isoleucine | 1.3 g | 1.4 g |
| Histidine | 0.8 g | 0.7 g |
Hemp's limiting amino acid for typical adult requirements is lysine; a single hemp serving does not meet the lysine target, though combined with other plant proteins (legumes are particularly lysine-rich) the daily total is easily achieved.
Seed versus protein powder
Hulled hemp seed: 10 grams protein per 30 grams, plus the natural fat and minerals. Hemp protein powder: typically 15 to 20 grams protein per 30 gram serving (50 to 65 percent protein by weight), with most fat pressed out during processing. For everyday food applications, hulled seed makes sense; for protein-focused goals (post-workout, low-fat dietary contexts), protein powder is more efficient.
Hemp protein blends
Plant protein products increasingly blend hemp with pea, rice, or sunflower seed protein. The rationale: hemp is lower in lysine but adequate in methionine; pea is lysine-rich but lower in methionine. Combined, the amino acid profile resembles dairy. Hemp also contributes a meaningful texture and mineral baseline that pea protein isolate alone lacks.