Is there any such thing as the best plant protein?

In recent years, plant-based products have gained popularity all over the world, leading many consumers to take an interest in these new products, whether for health or ethical reasons, or simply out of curiosity. Attention to these products has prompted manufacturers to improve their products more and more, seeking to also offer new protein bases other than the well-known soya. In this article, we’ll analyse the popular or emerging vegetable protein sources currently available, and also look at their most recent applications, in order to answer the question: what is the best vegetable protein on the market?

Established plant proteins: soya, pea, and rice

Soya is a legume that has been consumed by East Asian populations for more than 2,000 years. In the 1990s, it also gained popularity in the West due to its beneficial properties in the prevention of chronic diseases. Soya is an easy legume to purify and concentrate into protein and is valued for its high nutritional profile and excellent functional properties, whilst its strong “greeny taste” may limit its use and acceptance by consumers. In addition, soya is considered one of the top 14 allergens by the European Union, which makes it unsuitable for some people. Soya protein is widely used in various sectors, and according to Mintel GNPD, in 2022 it was used primarily in alternative products to meat, fish, milk, cheese, and eggs (35.9%), in snacks (22.3%), ready meals (13.5%), and protein drinks (7.1%). 

As a possible alternative to soya, recent years have seen a rise in the popularity of pea proteins, which are less allergenic than soya and have a good and complete amino acid composition. Nevertheless, the distinctly pronounced ‘beany taste‘ of peas may require the use of masking agents or flavourings to cover this. In addition, pea protein ingredients often have a high sodium content, making them unsuitable for people on a low-sodium diet. According to Mintel GNPD, in 2022 pea proteins (whether flour, concentrates, isolates or TVPs) were used in alternatives to meat, fish, and eggs (23.5%), nutritional drinks (14.0%), snacks (12.8%) bakery (10.8%), dairy products (10.1%), and ready meals (8.5%).

Rice proteins have been used for a long time, mainly to replace gluten in gluten-free products. Despite having an unbalanced amino acid composition, rice proteins are hypoallergenic, easily digestible and have a good taste and sensory profile but they also have a low solubility in water, which may affect their technical-functional characteristics such as their emulsifying capacity. On the other hand, rice proteins also have a high capacity to absorb water and oil and to create foam. According to Mintel GNPD in 2022, rice proteins (either flour, concentrates, isolates or TVPs) were used in nutritional and functional beverages (27.0%), snacks (23.9%), alternative products to meat, fish and eggs (15.6%), and bakery products (12.7%).

Emerging proteins: broad bean, mung bean, and sunflower seeds

The broad bean is considered one of the most promising new sources of protein due to its high quality and high protein content, which is higher than that of peas. Despite being a non-GMO legume, broad beans are still underused in the West. In fact, broad beans (also referred to as fava beans) are responsible for favism, where certain glucosides (divicine and convicine) of fava beans can result in the destruction of red blood cells (causing acute hemolytic anemia) in people displaying inherited G6PD deficiency (the enzyme glucose-6-phosphate dehydrogenase). Apart from that, the proteins obtained from the broad bean have good functional properties, such as the ability to foam, emulsify, and gel, which make them suitable for various uses in food preparation. According to Mintel GNPD in 2022, broad bean proteins (either flour, concentrates, isolates or TVPs) were used in nutritional and functional beverages (27.0%), snacks (23.9%), alternative products to meat, fish, and eggs (15.6%), and bakery products (12.7%).

The mung bean is another promising source of protein, particularly popular in Asia for its detoxifying, anti-cancer and anti-inflammatory properties. Traditionally, mung bean protein is considered a by-product of starch extraction, the main product of the process. However, in recent years, the mung bean has been increasingly exploited for its protein component, which is nutritionally interesting due to its protein concentration and functional properties, such as its high foam and gel-forming capacity. Its use still remains very limited, but according to Mintel GNPD in 2022 mung bean proteins (either flour, concentrates, isolates or TVPs) were used in alternative products to meat, fish and eggs (64.0%), snacks (16.0%), and nutritional drinks (12.0%).

Finally, sunflower seeds are an interesting emerging protein source due to their protein content, their amino acid profile and the fact that they are naturally allergen-free. Moreover, to date, there are no GMO sunflower varieties cultivated in the field. Sunflowers are mainly used for the production of oil, and the by-product of this process is a flour with a high protein content.  The use of sunflower protein in food is still limited because of the presence of chlorogenic acid, which can negatively impact its colour, and because of the commonly used extraction methods, which have negative effects of protein denaturation or are simply not usable for food purposes. However, several technologies can overcome these issues, making sunflower protein very promising for its neutral flavour and functional properties. Its use is currently still very limited, but according to Mintel GNPD in 2022 sunflower proteins (either flour, concentrates, isolates or TVPs) were used in nutritional drink powders (19.3%), alternatives to fish, meat, and eggs (15.6%), snacks (11.0%), and savoury spreads (11.0%).

Soya remains the best plant protein, however the need for new sources stands strong 

In summary, soya protein is widely used, but can cause allergies and has a strong taste. Pea proteins are a hypoallergenic alternative, but have a strong taste and often a high sodium content. Rice proteins are suitable for gluten-free products but have solubility limitations. Broad bean proteins have interesting properties but may pose a high risk for some people who suffer from favism. Other proteins, mung bean and sunflower protein seem promising, but are still under development and have penetrated the market only to a limited extent. Nevertheless, soya continues to remain the ‘best’ vegetable protein, due to a combination of several factors: high protein content, light colour, high functionality and above all its low price. However, for several years now, food manufacturers have already been moving towards a transition from the use of soya to new protein sources, giving numerous companies the opportunity to work on new models and extraction technologies. In the future, we could certainly expect more variety, from alternatives such as seed oils or even algae, and even blends between products, which could lead to functionally and nutritionally complete ingredients.