Pro Tip: Understanding the use of chickpea protein concentrates can help produce stable foams and gels.

Creating stable foams in baked goods like cakes and muffins is an important part of replacing key ingredients such as eggs or wheat flour in gluten-free products. However, achieving stable foams that can withstand processing and lead to baked goods with similar textures remains a challenge in the baking industry.

One ingredient that can help produce stable foams and gels is chickpea protein concentrates. Chickpeas are in the broader category of pulses, which are legumes that contain relatively low levels of oil, including lentils, peas and kidney beans. Whole chickpeas contain high levels of protein, typically ranging between 18% and 26% depending on the variety.

One of the most common methods of extracting protein from pulses for use in baked goods is isoelectric precipitation. This method involves mixing pulse flour in a solution that has an alkaline pH (pH 8 or higher) to increase the solubility of the protein. This is then followed by removing the solids from the solution through filtration or centrifugation before reducing the pH of the remaining liquid to a pH of ~4.5. This pH value is the isoelectric point of the protein, which is the point where the protein will be almost completely insoluble in water.

As a result, the protein becomes a solid that can then be filtered out and dried for use in baked goods. In most pulses, this leads to a protein isolate that is greater than 85% to 90% protein. However, in chickpeas, the concentrates made by this method often have high levels of carbohydrates, leading to protein contents between 70% and 80%. While this makes chickpea protein relatively less attractive as an ingredient for high-protein formulations, the added carbohydrate fraction has been shown to aid in the formation of stronger gels and more stable foams than other pulses.

In replacing wheat flour with chickpea flour in muffin formulations, it was found that increasing the amount of chickpea flour also increased the viscosity of the dough. This was partially attributed to the fact that chickpea protein can bind more water than wheat protein. Chickpea protein also had the ability to bind more water than other pulse flours.

As a result, formulations with chickpea flour should increase the total formula water to compensate for these effects. Additionally, it has been found that chickpea protein starts to form hard gels at concentrations between 10% and 14% if the protein is heated in water above the temperatures where the protein starts to unfold or denature, between 90°C (194°F) and 98°C (208.4°F).

As such, to be useful in replacing the gel strength imparted by eggs, relatively high levels of chickpea protein should be used to ensure that stiff gels form, providing a desirable texture in cakes or muffins.

Additionally, the product’s interior temperature should rise above 90°C (194°F) to induce protein denaturation, and therefore, gelation. Using this, it was found that replacing up to 20% of the eggs with chickpea protein in cakes led to final products with comparable volume to traditional cake formulations that also had high scores in sensory evaluations. However, increasing the concentration higher than 20% led to a decrease in the cake’s acceptability.

Harrison Helmick is a PhD candidate at Purdue University. Connect on LinkedIn and see his other baking tips at BakeSci.com.

His research is conducted with the support of Jozef Kokini, Andrea Liceaga, and Arun Bhunia.