A study from researchers in the US is exploring the potential of rice proteins in the development of hypoallergenic and sustainable cheese alternative products.

Mahfuzur Rahman, an assistant professor in the Department of Food Science for the Arkansas Agricultural Experiment Station, led the University of Arkansas study. He explained that the protein sources in rice are considered byproducts of white rice processing, adding value and potential domestic demand for one of the state’s leading crops.

In the study carried out by the Experiment Station (the research arm of the University’s agriculture division), a variety of proteins extracted from a single rice cultivar were shown to provide the necessary qualities for plant-based cheesemaking, including firm texture and meltability.

Unlocked opportunity for rice byproducts

Arkansas leads the US’ rice production, harvesting a record 1.43 million acres in 2024 that accounted for nearly 50% of the nation’s total rice production.

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 said that using these rice milling byproducts for protein extraction present a "significant opportunity to expand the US-based rice protein market while promoting a sustainable circular economy”.

According to the US Department of Agriculture, the US produced an estimated 14.3 million tons of rice bran and around 24.8 million tons of broken kernels annually in 2024, offering a potential yield of around 3.3 million tons of rice protein for the plant-based market.

Nutritional analysis

Brown rice contains about 15% protein, 15% fibre and 50% carbohydrates. Broken kernels, which can be used in beer brewing as well as pet food, contain around 7% protein, 75% carbohydrates and 1% fibre.

After chemically extracting protein from each rice section, the researchers made three different plant-based cheeses using a standard recipe with organic coconut oil and corn starch.

They also analysed the protein composition from each rice source. Rice proteins are composed of four major subunits: albumin, globulin, glutelin and prolamin, with glutelin being the largest fraction.

Analysis showed that rice bran contained the highest amount of albumin, while glutelin was higher in brown rice and kernel protein. The rice-based cheeses made from the rice byproducts contained about 12% protein – a significantly higher portion than many plant-based cheese alternatives currently available on the market, Rahman pointed out.

Functional properties

With sufficient foaming and emulsion capacities, Rahman also noted that the rice-sourced protein could replace the functions that eggs and oil provide in food chemistry.

While the study involved using hexane to extract the rice proteins, Rahman said he has been working on developing an ultrasound-based, non-chemical method of protein extraction to improve nutritional value. He is also working on extracting gluten from wheat flour using electrically charged plates.

According to the researchers, their study – published in the journal Future Foods – found that broken-kernel protein offered a softer texture with higher oil separation and melting properties, high glutelin content, moderate solubility, and emulsifying and foaming properties.

Brown rice protein was higher in essential amino acids and released more free amino acids during simulated digestion. It also demonstrated the highest solubility, emulsifying activity and emulsion stability.

Despite its lower solubility, rice bran protein showed significantly higher surface hydrophobicity. Its water-holding and foaming capabilities enhanced texture and minimised oil separation in cheese alternative prototypes.

Rahman said future studies on rice protein in alternative cheesemaking may focus on refining the cheese compositions and assessing sensory characteristics, customer acceptance and shelf-life stability.

“Current research is in progress to tackle these issues, facilitating the transition from laboratory development to practical use,” he added.