Pea Protein Explained: How It Is Made and How It Compares

Pea protein has become a familiar ingredient in plant based protein powders and foods. But how does a field pea become a fine protein powder? It involves more than simply grinding dried peas. Peas contain protein alongside starch, fibre and other components, so producing a protein rich ingredient requires separation or concentration. The method used can influence protein concentration, composition and functionality.⁵

Commercial disclosure: Amaris Mint® markets BioBoost Balance+ Protein™, which uses whey protein concentrate rather than pea protein. BioBoost is mentioned only where relevant to comparing protein sources.

What is pea protein?

Pea protein is a plant derived ingredient commonly produced from field peas, including yellow field peas (Pisum sativum). Processing separates or concentrates protein from starch, fibre and other components. Pea flour, pea protein concentrate and pea protein isolate are therefore not the same ingredient.

How is pea protein powder made?

There is no single process used for every pea protein ingredient. Two important approaches are dry fractionation and wet fractionation.⁵

Step 1: Cleaning and preparation

The peas are cleaned and, depending on the process, may be dehulled. They can then be milled into flour, reducing them into smaller particles that can be separated more effectively.

Step 2: Separating protein from other components

Peas contain protein rich structures alongside starch granules and fibre containing material. Manufacturers use differences between these components to produce a more protein rich fraction.

What is dry fractionation?

Dry fractionation separates components without first dissolving the protein in large quantities of water. After milling, technologies such as air classification can separate particles according to characteristics such as size and density.²

Dry fractionation generally produces protein enriched concentrates rather than the highly purified isolates associated with more extensive wet processing.³

Is dry fractionation more sustainable?

It can have resource advantages. Dry fractionation avoids some aqueous extraction and drying stages used in conventional wet processing, and studies have reported lower water requirements and, under some assessed conditions, lower energy use and environmental impacts.⁴⁶

This is not an absolute environmental claim. Performance depends on the process, equipment, energy source, yield, transport and assessment boundaries. A more accurate conclusion is that dry fractionation can offer resource advantages over conventional wet fractionation, depending on how the processes are designed and assessed.

What is wet fractionation?

Wet processing disperses pea flour in water and separates protein from other components using differences in physical and chemical behaviour. Some conventional processes adjust pH to increase protein solubility before other components are separated and the protein is recovered and dried. Wet fractionation can achieve higher protein purity, although processing conditions can affect protein structure and functionality.⁵

Pea flour, concentrate and isolate

Ingredient	Typical processing	Relative protein concentration	What remains
Pea flour	Milling	Lower	More starch, fibre and other pea components
Pea protein concentrate	Often dry or mild fractionation	Intermediate	More non protein components remain
Pea protein isolate	More extensive separation, commonly wet processing	Higher	Greater removal of starch and other components

Exact composition varies according to the ingredient and manufacturer. This is why the nutrition declaration and ingredient list matter more than assuming every product labelled pea protein has the same composition.

Does pea protein provide all nine indispensable amino acids?

Yes. Pea protein provides all nine indispensable amino acids, although their proportions and digestibility differ from those of other protein sources.

A human randomised trial comparing pea protein isolate with casein found mean real ileal amino acid digestibility of 93.6% for pea protein and 96.8% for casein, with no statistically significant difference in the overall measure. Some individual amino acids were less digestible from the tested pea protein.¹

The study calculated a DIAAS of 1.00 for pea protein isolate and 1.45 for casein.¹ These findings relate to the specific isolate studied and should not be assumed to apply identically to every commercial pea protein powder.

For more detail, read What Is a Complete Protein?

Pea protein vs whey protein

Feature	Pea protein	Whey protein
Source	Peas	Milk
Origin	Plant	Dairy
Provides all nine indispensable amino acids	Yes	Yes
Potentially suitable for vegan diets	Yes, depending on complete product	No
Contains milk allergen	Not inherently	Yes
Common forms	Concentrate and isolate	Concentrate, isolate and hydrolysate

The amount of protein supplied, amino acid profile, digestibility, allergens, other ingredients and overall diet all matter. Read our Whey Protein vs Pea Protein guide for a fuller comparison.

Why might someone choose pea protein?

Pea protein may appeal to someone following a plant based or vegan diet, avoiding dairy, seeking an alternative to whey or soya, or simply preferring a particular formulation. The suitability of the finished product still depends on everything it contains.

Is pea protein an allergen?

Pea is not one of the 14 allergens that UK food law requires businesses to identify and emphasise when present as an ingredient. This does not mean pea cannot cause an allergic reaction.

Reactions to pea can occur. People with known food allergies, particularly allergies to legumes, should check individual products carefully and seek appropriate professional advice where necessary. Other ingredients and potential allergen cross contact may also affect suitability.

How to choose a pea protein powder

Check protein per serving

Look at the amount provided by the serving you will actually use.

Check the protein ingredient

See whether the product uses pea protein concentrate, isolate or a blend.

Read the complete ingredient list

Protein powders may also contain flavourings, sweeteners, vitamins, minerals, fibres, botanicals or other ingredients.

Check allergens and suitability

Plant based does not automatically mean suitable for everyone.

Our How to Read Protein Powder Labels and Ingredient Transparency guides explain what to look for in more detail.

Where BioBoost Balance+ Protein™ fits

BioBoost Balance+ Protein™ uses whey protein concentrate as its principal protein source. It does not contain pea protein.

Pea protein is discussed here to help readers understand how different protein sources are produced and compared. BioBoost is positioned as a daily nutrition protein, with protein as its nutritional anchor.

For further reading, see Whey Concentrate vs Isolate, Whey Protein vs Pea Protein and How Is Protein Powder Made?

The practical takeaway

Pea protein powder is not simply dried peas ground into a fine powder. Producing a protein rich ingredient involves separating or concentrating protein from starch, fibre and other components.

Dry fractionation uses physical processes such as milling and air classification and can produce protein enriched concentrates. Wet fractionation uses aqueous separation processes and can achieve higher protein purity.³⁵

Read the label. Understand the protein source. Look at the complete formulation. Then decide whether it fits your diet and daily routine.

Amaris Mint® | The Swedish Daily Nutrition™ Routine.

References

1. Guillin FM, Gaudichon C, Guérin-Deremaux L, et al. Real ileal amino acid digestibility of pea protein compared to casein in healthy humans: a randomized trial. The American Journal of Clinical Nutrition. 2022. doi:10.1093/ajcn/nqab354. PubMed.
2. Pelgrom PJM, Vissers AM, Boom RM, Schutyser MAI. Dry fractionation for production of functional pea protein concentrates. Food Research International. 2013;53(1):232–239. DOI.
3. Schutyser MAI, Pelgrom PJM, van der Goot AJ, Boom RM. Dry fractionation for sustainable production of functional legume protein concentrates. Trends in Food Science & Technology. 2015;45(2):327–335. doi:10.1016/j.tifs.2015.04.013. DOI.
4. Schutyser MAI, van der Goot AJ. The potential of dry fractionation processes for sustainable plant protein production. Trends in Food Science & Technology. 2011;22(4):154–164. doi:10.1016/j.tifs.2010.11.006. DOI.
5. Yellow Field Pea Protein (Pisum sativum L.): Extraction Technologies, Functionalities, and Applications. Contemporary review of yellow field pea processing, dry and wet fractionation and ingredient functionality. Full text.
6. Allotey DK, Kwofie EM, Adewale P, et al. Techno-eco-environmental assessment of dry fractionation of protein concentrates from yellow peas with different pre-treatment methods: An eco-efficiency approach. Journal of Cleaner Production. 2024;457:142298. doi:10.1016/j.jclepro.2024.142298. DOI.