Investigating the efficacy of plant protein functionality as a replacement for egg
22 July 2025 | Elena Sharma, Food and Drink Science Team Lead, and Jo Baker Perrett, Technical Manager, Product Innovation
When it comes to food and beverage products, the functionality of each ingredient is one of the most important factors behind its inclusion, as each ingredient delivers its own properties and benefits - with egg being no exception to this.
Eggs provide a range of functionalities ranging from gelling and air entrainment to foaming and emulsification, all of which are valuable attributes for food and beverage products. They can also be used for flavour and colour; and are often used to glaze various baked goods to achieve an attractive shine and golden-brown colour when cooked. In addition, the fats in egg yolk not only contribute significantly to the structure formation and binding of baked products but can help soften their texture and ensure a moist mouthfeel.
Yet, due to growing consumer interest and considerations around sustainability, ethics and health, we are seeing a move away from egg ingredients in some products and more enquiries about vegan and plant protein-based alternatives, particularly in bakery.
What are plant proteins and how can they help?
Plant proteins are essentially proteins derived from different plant sources that typically include legumes (e.g. soybeans, peas and lentils), grains (e.g. rice and quinoa), vegetables, nuts and seeds.
These proteins, which can be extracted from plants, are becoming increasingly popular in food production due to their health benefits, sustainability and versatility. And thanks to their ability to enhance the texture, flavour and overall sensory experience of food products, plant proteins can also help manufacturers meet growing consumer demand for clean label products, by replacing synthetic additives and the overall number of ingredients in foods.
Plant proteins can in some cases be more cost-effective and simpler to source than animal proteins too, particularly in regions where certain crops are more abundant
The challenge for food manufacturers wanting to reformulate their ingredients
The use of plant proteins can be an attractive proposition for any food manufacturer looking to reformulate their product and substitute egg, dairy or meat proteins with a plant protein alternative.
However, it is not as simple as just replacing one ingredient with another. We also need to consider the product that a particular manufacturer is working with and the functionality and attributes that its food ingredients contain to deliver quality in that product.
If you consider a food product like cake for example, there will be inherent properties within its different ingredients, which all help to deliver a good quality cake - with egg offering a great example.
Generally, the most desirable cakes rely on achieving a high volume and a soft texture. And if we revisit the functionality of egg proteins that we outlined earlier, it’s exactly those attributes that enable the cake to expand well in the oven and achieve a soft but firm homogeneous structure.
As a highly functional ingredient, that enables strong gelling, foaming and emulsification, egg can be challenging to effectively replace, especially with a single ingredient. Yet while plant proteins can also be highly functional, not all plant proteins can provide all of these functionalities in one ingredient like the egg can. This provides a real challenge for food manufacturers along with trying to identify the best plant protein functionality from a wide variety of potential plant ingredients.
To help with this manufacturers’ need to be able to call on real data and trials to see how well the functionality of different plant proteins compares with egg.
It is for these reasons that we set out to help manufacturers by evaluating the effectiveness of a range of plant-based ingredients as egg replacers, focussing specifically on the baking of cakes.
Helping manufacturers become better informed about plant-based alternatives
Through our ongoing trails, we set out to test how different plant proteins including fava bean protein isolate, lentil protein concentrate, potato protein isolate and mung bean isolate performed in cake baking compared to liquid and powdered egg alternatives. We also included a negative control that contained no egg or replacer ingredients.
As well as measuring the individual properties of the proteins – how well they emulsify, foam and alter batter rheology – they were also baked into a cake and the quality was analysed (texture, batter density and volume).
The top-level results of our ongoing trials of cake baking with the different proteins using a standard cake recipe are:
- Liquid egg cakes were the softest, highest volume and entrained most air in the batter.
- Powdered egg was quite soft, but with less air entrained and a lower cake volume.
- The negative control was quite soft, with the least air entrained yet the 3rd highest cake volume.
- Lentil protein was the softest of plant proteins, with low entrained air but the highest volume of plant proteins.
- Potato protein was very hard, entrained the most air of plant proteins yet with the lowest volume.
- Mung bean and fava bean were intermediate in all respects.
The real value in this investigation was uncovering why one cake was worse than another, therefore giving us the tools to adjust the recipe and hopefully improve the cake quality. Traditional approaches to recipe development rarely have such data to back up recipe changes.
Functionality findings revealed
Cake softness was improved by:
- Better emulsification of liquid oil: proteins which had a lower interfacial tension and made a more stable test emulsion made softer cakes.
- A higher cake volume.
Cake volume was driven by:
- Once again, better emulsification of liquid oil.
- Decrease in the surface tension (SFT) of a protein solution.
- A higher gel strength when hot.
While our current findings should give manufacturers more confidence about the sort of baking performance they can achieve using different plant proteins, it is important to note that these trials are ongoing, as we are aware that there are still some customer questions that need answering. We would like to examine if tweaking the recipe to improve important aspects such as emulsification, could take the plant protein recipes closer in quality to the egg cakes.
How Campden BRI can support you with your product reformulation needs
When it comes to product reformulation, Campden BRI can support you with the reduction or replacement of key ingredients such as egg, including the investigation into alternative ingredients such as plant proteins.
Whatever your reformulation needs, Campden BRI can offer application trials to help you find suitable potential alternatives with which to reformulate your product. We can also perform functionality testing to find the optimal conditions and recipe to achieve the best results from a particular ingredient that you wish to use.
For functionally important ingredients like egg, it is not always immediately obvious what functions your raw material is delivering. Campden BRI can ensure that this functionality is fully understood for your specific product, while offering support in identifying the best alternatives and guiding you through all stages of the product development process.
Campden BRI has an extensive suite of analytical equipment, pilot scale facilities and scientific expertise to help food producers and manufacturers understand their ingredients and products. Our technical experts can then help your company to leverage this information for the successful production of egg-free products and plant protein-based alternatives.
About Jo Baker-Perrett
After graduating from his master’s degree in chemistry from the University of Sheffield in 2014, Jo worked in education before joining us in 2016. Since then, Jo has worked in the bakery department, and then in Food and Drink Microstructure, after which he started managing this section, which is mainly focused on physical characterisation and ingredient functionality.
Jo has published various Campden BRI research reports and trade press articles, as well as producing regular food industry blogs for our website.
How can we help you?
If you would like support with your plant-based innovations or any of your reformulation needs, contact us to find out how we can help.
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