By John Lovett
University of Arkansas System Division of Agriculture
FAYETTEVILLE, Ark. — For vegans and people who are allergic to dairy, nuts or gluten, rice is a surprising source to make a hypoallergenic alternative cheese.
As a bonus, the protein sources in rice are considered byproducts of white rice processing, adding value and potential domestic demand for one of Arkansas' leading crops, says Mahfuzur Rahman, assistant professor of food science with the Arkansas Agricultural Experiment Station.
Rahman and his food science graduate student, Ruslan Mehadi Galib, recently published a study in the journal Future Foods that provides more understanding of the capabilities of rice proteins for hypoallergenic alternative foods. The experiment station is the research arm of the University of Arkansas System Division of Agriculture.
A variety of proteins extracted from a single rice cultivar were shown to provide qualities needed for plant-based cheesemaking, including firm texture and meltability.
"In a single rice grain, we have three different types of protein — from brown rice, white rice and bran," said Rahman, who is also part of the Dale Bumpers College of Agricultural, Food and Life Sciences at the University of Arkansas. "That's the fundamental understanding we wanted to develop. When you say, 'rice protein,' what does that mean? Is it brown rice protein? Bran protein? Broken kernel protein?"
Circular economy opportunity
Arkansas is the leading rice producer in the United States , harvesting a record 1.43 million acres in 2024 that accounted for nearly 50 percent of the nation's total rice production. According to the U.S. Department of Agriculture , the study points out that in 2024 the U.S. produced an estimated 14.3 million tons of rice bran and 24.8 million tons of broken kernels annually, offering a potential yield of about 3.3 million tons of protein for the plant-based protein market.
Currently, companies import and distribute rice protein within the U.S. market, the study added. Rahman pointed out that using these rice milling byproducts for protein extraction presents a "significant opportunity to expand the U.S.-based rice protein market while promoting a sustainable circular economy."
During rice milling, the dehulling process removes the husk, yielding brown rice. Further milling of brown rice produces white rice, along with rice bran and broken kernels as byproducts, Rahman explained.
Brown rice, bran and broken white rice kernels contain valuable nutritional components. For example, rice bran consists of about 15 percent protein, 15 percent fiber and 50 percent carbohydrates. Broken kernels, which can be used in pet food and beer brewing, contain about 7 percent protein, 75 percent carbohydrates and 1 percent fiber.
Say 'cheese'
After chemically extracting protein from each rice section, the food scientists made three different plant-based cheeses using a standard recipe with organic coconut oil and corn starch.
They also analyzed the protein composition from each rice protein source. Rice proteins are composed of four major subunits: albumin, globulin, glutelin and prolamin, with glutelin being the largest fraction.
Analysis of the protein sources showed that rice bran contained the highest amount of albumin. In contrast, glutelin was higher in brown rice and kernel protein. The rice-based cheeses made from the rice byproducts contained about 12 percent protein. Usually, plant-based cheese lacks protein, or has none, Rahman noted.
Overall, Rahman said, the study established a clear relationship between the different sources of rice-based proteins and their functional performance in food products. With sufficient foaming and emulsion capacities, Rahman said the rice-sourced protein may also be able to replace the functions that eggs and oil provide in food chemistry.
Knowing what each part of rice can do also provides guidance on developing different types of plant-based cheeses.
While the researchers used hexane to extract the rice proteins, Rahman has been working on developing a non-chemical method of protein extraction using ultrasound to improve nutritional value. He is also working on extracting gluten from wheat flour using electrically charged plates.
Other key findings from the rice protein study:
- Broken-kernel protein had a softer texture with higher oil separation and melting properties, with high glutelin content and moderate solubility, emulsifying and foaming properties.
- Brown rice protein was higher in essential amino acids and released more free amino acids during simulated digestion. It also showed the highest solubility, emulsifying activity and emulsion stability.
- Rice bran protein, despite its lower solubility, showed significantly higher surface hydrophobicity. Its strong water-holding and foaming capacities enhanced the texture and minimized oil separation in cheese prototypes, suggesting potential for use in plant-based systems.
Looking ahead, Rahman said future studies on rice protein in alternative cheesemaking may concentrate on refining the cheese compositions and assessing sensory characteristics, customer acceptance and shelf-life stability to improve consumer acceptance.
"Current research is in progress to tackle these issues, facilitating the transition from laboratory development to practical use," Rahman said.
Ruslan earned his master's degree from the department of food science in January and is now pursuing a doctorate in the department of chemical engineering in the College of Engineering at the University of Arkansas.
To learn more about ag and food research in Arkansas, visit aaes.uada.edu
