The enduring popularity of soy among plant proteins

27 May 2019

Novel protein sources like peas, hemp, nuts, seeds, algae and legumes are on the rise, but soy protein continues to be the industry’s go-to plant protein. Why does it continue to lead the pack – and is there any other ingredient with the potential to topple soy from its number one spot?

Soy protein dominates among plant proteins, accounting for 56% of the global market, according to Leatherhead Food Research. However, pea protein is one of the fastest growing protein sources in new product launches, and it has particular potential as a less common allergen than soy or wheat. In addition, Leatherhead has highlighted algae as another strong contender among plant protein sources, calling it “perhaps the most abundant protein on the planet”.

The enduring popularity of soy among plant proteins
Soy has many benefits among plant proteins

There are several reasons for soy’s popularity. Firstly, it is cheap and widely available, considering – somewhat ironically – that it is one of the world’s biggest sources of protein for animal feed (alongside corn), so it benefits from economies of scale, as well as subsidised production in the United States. It is also a complete protein, providing the full complement of essential amino acids, making it a good vegan alternative to animal proteins in sports nutrition products in particular. Pea and hemp are also plant-based sources of complete protein, but each source is different in how it is digested, meaning that bioavailability could be affected. Pea protein, for example, contains lower levels of the amino acid methionine and its digestibility is limited by other components, such as tannins.

However, complete protein is less important for plant protein products beyond those intended for sports nutrition, such as meat alternatives, considering that even vegans very easily meet all their protein requirements over the course of a day simply by eating a varied diet.

Ease of processing is another important factor, and soy protein isolates are easily processed into other forms. What is more, food manufacturers have been using soy protein for vegetarian meat alternatives for decades, meaning there is an existing wealth of knowledge around its functional potential and its limitations.

Recently, however, manufacturers and food technologists have been making strides with other protein sources, including algae and peas. But even as major plant protein companies like Beyond Meat have chosen pea protein for their products, some have raised questions about the reliability of supply in a rapidly growing market. Ingredient suppliers, including Cargill, Roquette and DuPont Nutrition & Health, have ramped up both their sourcing and processing capabilities to meet anticipated high demand.

Considering rising interest in plant proteins among wealthy meat-eaters in particular, taste is likely to remain the most important factor for many consumers when considering different plant protein ingredients and formulations. Although industry know-how regarding soy protein makes it the current frontrunner among plant protein ingredients, ongoing research and development in the space means other ingredients could usurp its place – as long as flavour is front and centre.