Study · Scientific reports · 2024Conflicts declared

Rice bran oil blended with soya oil during 12 months of storage

What it found

Blending soya oil with rice bran oil slowed the rise in free fatty acids, peroxide value and TBA over 12 months of storage at room temperature.

The blends stayed within recommended limits for free fatty acids and peroxide value.

What they found

Fresh oil quality

The fresh oils had low initial values of free fatty acids, peroxide value and TBA. Rice bran oil contained gamma oryzanol, which the other oils did not contain.

Fatty acid makeup

Soya oil had more unsaturated fat than rice bran oil. As more rice bran oil was added, oleic acid went up and linoleic and linolenic acids went down.

Oxidative stability

Rice bran oil had the longest induction period at 24.08 hours, followed by the blend with 75% rice bran oil at 23.44 hours. Pure soya oil had the shortest at 18.3 hours.

Free fatty acids in storage

Free fatty acids rose in all samples over 12 months. The final values ranged from 0.18% to 0.26%, and blends with rice bran oil rose less than pure soya oil.

Peroxide value in storage

Peroxide value rose faster in pure soya oil than in the blends. Adding rice bran oil significantly slowed the rise in hydroperoxides.

TBA in storage

TBA rose in all samples over 12 months. In soya oil it went from 0.533 to 1.446 mg malonaldehyde/kg oil, and in rice bran oil from 0.336 to 0.882 mg malonaldehyde/kg oil.

What the authors conclude

“In general, it can be inferred that the substitution of soybean oil with rice bran oil in the formulation of edible oil blends confers a greater inhibitory effect against oxidation, thereby enabling an extended storage period without the incorporation of industrial antioxidants.”
Mohammed AS, Hashem HAA, Abdel Maksoud BS, 2024

Also in their conclusions

  • They say that substituting soya oil with rice bran oil in edible oil blends gives a greater inhibitory effect against oxidation.
  • They say this allows a longer storage period without adding industrial antioxidants.
  • They report that free fatty acids and peroxide values in all the tested blends stayed within the limits recommended for human consumption.

How it was done

The authors wanted to see whether rice bran oil could replace part of the soya oil in edible oil blends, to make the oil more resistant to oxidation and rancidity during use and storage.

They blended soya oil with rice bran oil at 25%, 50% and 75% rice bran oil, then stored the pure oils and the three blends at ambient room temperature for 12 months. Every month they measured free fatty acids, peroxide value and thiobarbituric acid.

What it can’t tell you

  • This study looked only at chemical measures of oil quality during storage, not at health effects in people.
  • It did not test how the oils or blends affect health when eaten.

The paper

Title
Improving the quality properties of soybean oil by using rice bran oil
Type
Study
Summarised from
Full text
Cite
Mohammed AS, Hashem HAA, Abdel Maksoud BS (2024). Improving the quality properties of soybean oil by using rice bran oil. Scientific reports. doi:10.1038/s41598-024-53059-3Free full textPubMed 38302565DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error