Which protein is found in pulses? An In-depth Guide to Legume Proteins

November 25, 2025 •

3 min read

According to the Food and Agriculture Organization, pulses can contain between 20-30% protein, making them a cornerstone of plant-based diets. The primary answer to which protein is found in pulses is a group of storage proteins called globulins, with the most prominent types being legumins and vicilins. These proteins provide essential amino acids and contribute significantly to the nutritional and functional properties of pulses.

Quick Summary

The majority of protein in pulses consists of globulins, predominantly legumins and vicilins, along with smaller quantities of albumins, glutelins, and prolamins. The specific protein composition varies by pulse type, affecting digestibility and amino acid profile, particularly for sulfur-containing amino acids.

Key Points

Main Protein Types: The primary protein found in pulses is a category of storage proteins called globulins, which include legumin (11S) and vicilin (7S).
Majority Protein Content: Globulins make up a significant majority of the protein in pulses, typically accounting for 70-80% of the total protein content.
Minor Protein Components: Besides globulins, pulses also contain smaller amounts of water-soluble albumins and other proteins like glutelins and prolamins.
Amino Acid Profile: Pulse proteins are often rich in lysine but may be limited in sulfur-containing amino acids like methionine and cysteine.
Protein Varies by Pulse: The specific ratio of different protein types, such as the legumin to vicilin ratio, varies across different pulse species and cultivars.
Benefits of Combination: Combining pulses with cereals, which are often high in methionine, can create a complete and balanced protein source.
Health Benefits: Pulse proteins and derived peptides offer health benefits, including antioxidant, anti-inflammatory, and blood pressure-lowering effects.

The Primary Proteins in Pulses: Globulins

Pulses are dry, edible seeds from legume plants, and their protein content is predominantly made up of storage proteins known as globulins. These proteins are essential for seed germination and typically constitute 70-80% of the total protein found in pulses. The globulins are further divided into two major types based on their molecular size and structure:

Legumins (11S Globulins): These are larger proteins, forming a hexameric structure. They generally contain higher amounts of sulfur-containing amino acids, such as methionine and cysteine, compared to vicilins, though these are still often limiting in pulses.
Vicilins (7S Globulins): Comprising trimers, vicilins are smaller than legumins and typically lack sulfur-containing amino acids. Their ratio to legumins can vary between pulse species and even different cultivars, affecting the overall nutritional quality.
Convicilin: In some pulses like peas, a third type of globulin called convicilin (7S) is also present in smaller quantities. Unlike vicilins, it does contain sulfur-containing amino acids.

Other Protein Fractions

While globulins are the most abundant, pulses also contain other protein fractions in smaller amounts:

Albumins: These are water-soluble metabolic proteins, such as enzymes, protease inhibitors, and lectins, and typically make up 10-20% of the total protein. They are generally richer in sulfur-containing amino acids than globulins.
Glutelins and Prolamins: Present in minor quantities (less than 5-10%), glutelins are soluble in dilute acids or bases, while prolamins are soluble in alcohol.

Comparison of Major Proteins in Pulses

This table outlines the key differences between the major protein types found in pulses, helping to clarify their roles and characteristics.


Feature	Globulins (Legumins & Vicilins)	Albumins	Other Proteins (Glutelins, Prolamins)
Function	Primary seed storage protein	Metabolic and enzymatic functions	Minor structural or storage functions
Percentage of Total Protein	~70-80%	~10-20%	<10%
Solubility	Soluble in dilute salt solutions	Soluble in water	Solutelins in dilute alkali/acid; Prolamins in alcohol
Amino Acid Profile	Rich in aspartic and glutamic acids; limited sulfur amino acids (methionine/cysteine)	Generally higher in sulfur-containing amino acids and lysine	Variable, but typically minor contribution
Structural Characteristics	Oligomeric, with legumins being hexamers and vicilins being trimers	Lower molecular weight proteins	Variable

Factors Influencing Pulse Protein Composition and Quality

The type and quantity of protein in pulses are not static and can be influenced by several factors, including:

Cultivar and Genetics: Different species and varieties of pulses have varying ratios of legumins to vicilins, which impacts the amino acid balance.
Environmental Conditions: The growing environment, such as soil quality and temperature, can alter the protein content and composition. For example, sulfur-deficient soil can lead to a lower proportion of legumins.
Processing Methods: Cooking, soaking, and fermentation can affect protein structure and digestibility by inactivating anti-nutritional factors like trypsin inhibitors and tannins. These processes can also enhance the protein's functional properties.

Nutritional Significance of Pulse Proteins

Despite some pulses being low in sulfur-containing amino acids, their overall nutritional value is high due to a strong amino acid profile that is particularly rich in lysine. This makes them an excellent complement to cereals, which are typically low in lysine. Combining pulses with grains can create a complete and balanced protein source. Beyond providing essential amino acids, pulse proteins and peptides derived from them have been shown to have health-benefiting properties, such as antioxidant, anti-inflammatory, and blood pressure-lowering effects. These benefits underscore why pulses are a valuable component of a healthy diet, particularly for vegetarians and vegans. Research continues to uncover the full potential of pulse proteins in food manufacturing and nutraceutical applications.

Conclusion

The protein in pulses is primarily composed of globulins, specifically legumins (11S) and vicilins (7S), which serve as the seeds' main storage proteins. While these are the most abundant proteins, smaller amounts of albumins and other fractions also contribute to the nutritional and functional characteristics. The specific protein makeup varies significantly between different types of pulses, a factor that influences their amino acid profile, structure, and digestibility. These proteins, particularly when combined with cereals, offer a complete and inexpensive source of high-quality protein, crucial for addressing nutritional needs and promoting overall health. The versatility of pulse proteins, along with their associated health benefits, positions them as a vital food component for sustainable and healthy diets worldwide.

Frequently Asked Questions

No, pulses are generally not considered a complete protein source on their own because they are low in the sulfur-containing amino acids methionine, cysteine, and tryptophan. However, they are rich in lysine, making them an excellent complementary protein source when paired with cereals like rice or wheat to achieve a full amino acid profile.

Legumin (11S) and vicilin (7S) are both major types of globulin storage proteins found in pulses. The main differences lie in their size and structure; legumins are larger, hexameric proteins, while vicilins are smaller, trimeric proteins. Additionally, legumins typically contain more sulfur-containing amino acids than vicilins.

Environmental factors during plant growth, such as soil nutrient levels, can significantly affect the protein composition of pulses. For example, studies show that growing conditions with sulfur deficiency can reduce the synthesis of legumins.

No, the protein composition varies depending on the type of pulse. Different species, like chickpeas, lentils, and peas, have different proportions of globulins, albumins, and other protein types.

Yes, cooking and other processing methods, such as soaking or fermentation, can impact the protein in pulses. These processes can help inactivate anti-nutritional factors and improve protein digestibility, making the nutrients more available to the body.

Albumins in pulses are water-soluble proteins that primarily serve metabolic and enzymatic functions. They are also generally richer in sulfur-containing amino acids compared to globulins.

Pulse proteins are important for a healthy diet because they are a cost-effective, sustainable, and nutrient-dense source of plant-based protein. They offer health benefits such as supporting heart health and aiding in weight management due to their high fiber and protein content, which promotes satiety.