Formulators must optimize extrudate by balancing different plant proteins and starches to achieve the desired texture and nutritional goals. Also, processing parameters play a crucial role in the final product quality, according to Michael Valenti, manager, global innovation business lead for protein fortification, Ingredion Inc .

“Pulse protein isolates deliver protein fortification and control expansion, giving consumers the protein levels they desire,” he said. “Pulse protein concentrates deliver protein fortification; however, pulse protein concentrates also contain a balanced nutritional profile with protein, fiber and micronutrients. They also contain higher levels of starch, which can improve the overall texture of an extruded snack while achieving protein and fiber goals.”

Pulse flours provide essential expansion characteristics for snack extrusion, Valenti added. 

“The choice of flour base will impact the final texture, allowing formulators and brand managers to create extruded snacks that align with their target customers’ texture preferences,” he said. “Pulse flours also contain higher levels of protein and fiber, compared to common sources of starch in extruded snacks, such as corn, rice, etc. This can assist with achieving nutritional targets.”

Pulse-based starches may also be added to the extrudate. Their fiber content helps provide uniform cell structure, providing consumers a consistent eating experience with every bite.

Ancient grains, such as quinoa and sorghum, along with plant-based protein isolates and concentrates, are becoming more common in extruded snacks. GoGo Quinoa, Laval, Canada, makes a puff snack where quinoa is the first ingredient, followed by sunflower oil and sorghum flour. Pea protein is the sixth ingredient. A 50-gram serving contains 230 calories, 6 grams of protein and 3 grams of fiber.

“Individual plant-based proteins and blends that include pea, soy and other protein ingredients are increasingly utilized in extruded snacks to boost their overall protein content and nutritional profile,” said Mike Medina, global marketing director, savory, ADM.

Consumers are curious and open to trying different protein options, not placing as much importance on the specific protein source itself, according to the ADM Outside Voice, Global Protein Consumer Discovery Report, 2023. 

“Given that, we see blends as an important factor in moving protein innovation forward,” said Manjot Singh, extrusion scientist at ADM. “They expand the range of options consumers have while providing an introduction to alternative protein sources. We are combining animal- and plant-derived proteins, as well as combining recognizable plant proteins, like soy, pea and wheat, with emerging sources, like chickpea, quinoa and navy beans.”

Soy proteins are often part of the blend. It is one of the few nonanimal proteins that is a complete protein with a Protein Digestibility Corrected Amino Acid Score (PDCAAS) of 1, enabling exceptional protein content in a variety of applications. 

“Soy protein isolate stands out among many plant protein sources due to its availability, high-protein content and best protein quality, as well as a cleaner flavor profile,” Luping Ning, design manager, bars, confectionery, fruits and cereals, IFF, said. “It requires the least amount of soy protein to deliver the targeted protein content and as a result, use of soy protein isolate in an extruded snack has minimal impact on its processing and product quality.”

There are a wide range of soy protein isolates with various functional properties. Therefore, selection of the right type of soy protein isolate is critical in delivering the desirable texture and taste. 

Like soy, quinoa is also a complete protein. This small, light-colored, round gluten-free grain has an unmistakably nutty, earthy flavor that works well in extruded snacks, alone or with other plant-based ingredients.

“Our blends of pea and wheat proteins, which combine the best characteristics from each plant source, result in enhanced taste and texture, as well as improved protein diversity,” Singh said. “Blends tend to have higher PDCAAS than the individual sources can provide.”

Manildra Group USA provides wheat proteins for extruded snacks. The range includes options to deliver different sensorial experiences. 

“We can really focus on balancing processing and texture by specific protein choices,” said Brook Carson, vice president of research and development at Manildra. “For example, a strong protein like vital wheat gluten might add the needed rigidity to your extruded piece, whereas a wheat protein with different properties could help to promote aeration and puff in the extruded piece. The viscoelastic and film-forming properties of wheat protein make them interesting in extruded snacks, when used alone or alongside other proteins.”

One of the reasons proteins vary in their impact on texture is due to their water-binding properties. This makes blending proteins an attractive approach to formulating.

“To get a soft, tender puff, you want the protein to release water during the expansion, which will improve eating properties,” Carson said. “A protein that binds a lot of water and doesn’t expand will give you a dense, tough bite. It’s all about balancing different proteins.”

Angel Yeast offers microbial proteins designed specifically for use in extruded snacks. Yeast protein is rich in essential amino acids, with a balanced ratio of 0.91 between essential and nonessential amino acids, which is higher than soy protein and comparable to whey protein, according to Chris Guo, director of nutrition and flavoring technology at Angel Yeast.

The snacking trend shows no signs of subsiding. What continues to change is what consumers want from snacks. For many, these mini meals need more protein for everyone to be satisfied.

This article is an excerpt from the November 2024 issue of Baking & Snack. To read the entire feature on Plant-based Protein, click here.