Microwave technologies can give hummus longer shelf life, eliminating need for chemical preservatives

Sadie Harley
scientific editor

Robert Egan
associate editor

Washington State University scientists are using microwave technology to extend the shelf life of hummus while eliminating the need for chemical preservatives, as demonstrated in a paper.
The Middle Eastern dip, which is growing in popularity around the world, was associated with between 2000 and 2018 that resulted in 65 hospitalizations and five deaths. Because of those outbreaks, many commercial hummus makers use chemical preservatives to extend shelf life and prevent the development of pathogens.
Now, WSU researchers, led by Shyam Sablani, a professor and corresponding author on the paper, are using technology to make the food more shelf stable. One process, microwave-assisted pasteurization, is a milder treatment that produces better-tasting hummus and keeps it fresh for up to 30 days in a refrigerator if unopened.
The other process, microwave-assisted sterilization, is harsher. It reduces flavor intensity but ensures hummus can be stored at room temperature for two years if unopened.
The two technologies, developed by Juming Tang and his team at WSU, use the same microwaves to produce high-quality food with extended shelf lives in different storage conditions. The technology allows for predictable and rapid heating of pre-packaged food that eliminates food pathogens and replaces traditional industrial methods such as canning.
"After testing for storage, quality, texture, color, and vitamin retention, both processes held up quite well," said Sablani, who is in WSU's Department of Biological Systems Engineering. "I tried it several times and thought it tasted very good."

Instead of using chickpeas, the most common primary ingredient, Sablani and his team made lentil-based hummus for their research. It's unusual, but Sablani said visiting researcher Burcu Tenderis, the paper's lead author, had heard of communities in her native Turkey that used lentils.
Lentils are cheaper and more readily available, especially in the U.S. Tenderis conducted many different trials to create a lentil hummus that worked, said Sablani, who is currently in Thailand as a Fulbright Scholar.
"Water absorption abilities and the chemical makeup of the two legumes are quite different," he said. "I'm from India and have often made chickpea hummus at home. It never occurred to me or anyone else in our lab to use lentils. For me, it wasn't too different, and I really enjoyed it."
The researchers also enriched the hummus with vitamin C, documenting how much remained after the microwave treatments.
"Lentils and other grains, along with most vegetables, are not rich in vitamin C," Sablani said. "Vitamins are heat-sensitive, so you lose a significant amount of them while cooking. We measured how much remained after each process so we knew how much to enrich the product later."

The microwave process retained 75% of the vitamin C, a good sign for the team.
The next step will hopefully be asking panels to evaluate responses to taste, smell, and other sensory attributes, Sablani said.
"This project was part of the Soil to Society program, which looks at how to get healthy, nutrient-rich grains into publicly available food," he said. "That program provided the funds for this research, but now we are looking for industry partners to commercially produce the product. If that's successful, then commercialization would follow, and consumers could see the end results."
Though that could be several years away, Sablani is excited about the research's prospects.
"It's important to have safe, shelf-stable foods that provide a variety of healthy nutrients," Sablani said.
More information: Burcu Tenderis et al, Development of Vitamin C鈥怑nriched Lentil Hummus With Innovative Microwave Technologies, Journal of Food Process Engineering (2025).
Provided by Washington State University