Pumpkin Seed Protein Gives Nondairy Creamer Twist

" Dual-Phosphorylated Pumpkin Seed Protein Pickering Emulsions: Structural Evolution, Interfacial Regulation, and Coffee Creamer Application Quality "Journal of Agricultural and Food Chemistry

Pumpkin season is about more than cute décor. The squash contains lots of seeds with a high protein content, but they're usually discarded. Researchers reporting in ACS' Journal of Agricultural and Food Chemistry found another way to use the seeds, extracting that protein to create a plant-based coffee creamer. In initial taste tests, participants preferred the new creamer to a commercial nondairy option because it preserved the flavor and aroma of coffee better.

Some pumpkin seeds are eaten, but most are either thrown out or processed for their oil, which leaves behind a food product that's mostly protein. But this protein clumps in water, which limits its upcycling and incorporation in plant-based beverages. Previous food science research has shown that a group of chemical compounds called phosphates can help proteins form stable mixtures of oil and water, also called emulsions. So, Jicheng Chen, Jianyu Huang, and colleagues wanted to treat pumpkin seed protein with food-grade phosphates and test the product's potential as a satisfying, nondairy coffee creamer.

The researchers first added different proportions of two phosphate salts to pumpkin seed protein extracts and measured the resulting powder's ability to create smooth, stable emulsions. A blend of two widely used food texture modifiers and thickeners, sodium tripolyphosphate and sodium trimetaphosphate, in a 4:1 ratio performed best. The researchers mixed the powder into water and whipped the mixture with camellia oil, also known as tea seed oil, creating a prototype nondairy coffee creamer.

Next, the team poured the emulsion into instant black coffee prepared with room-temperature water.

A 10% creamer addition was chosen for taste tests because it slightly lightened the coffee's color without substantially impacting the aroma, an effect that consumers expect from coffee creamers. In a taste test conducted by 12 people, participants preferred coffee with the pumpkin seed protein creamer over coffee containing a commercial nondairy creamer. They said that the commercial creamer improved the drink's texture but was less effective at reducing the bitterness of the coffee and could add some off-flavors. In contrast, while the pumpkin seed creamer also improved the drink's appearance, body, and smoothness, it retained the expected flavor and aroma of coffee.

Jicheng Chen says these findings show that "a plant-based coffee creamer can improve mouthfeel without sacrificing the coffee's own flavor."

And with further development, the pumpkin seed-based creamer has the potential to be a product found on store shelves. The team plans to explore the new nondairy creamer's stability in coffee (as well as other beverages such as beer), evaluate its flavor and consumer acceptance, and develop it into liquid concentrates or powders for easy storage and transport, says Jicheng Chen.

The authors acknowledge funding from the Fujian Science and Technology Mission Serves Key Industrial Chain projects, and the Major Scientific and Technological Projects in Fuzhou. They also thank Fujian Agriculture and Forestry University for its encouragement and support of the researchers.