Oryzan™ Rice Bran Oil: An Excellent Frying Oil

The RITO Partnership (Riceland Foods & Oilseeds International Ltd.) has been commercially extracting and refining edible oil from rice bran since 1994. Oryzan™ rice bran oil is extracted from the bran layers of rice. Rice bran oil inherently contains a high level of gamma oryzanol, a natural mixture of ferulic acid esters. Oryzan™ is processed by a non-conventional vegetable oil refining technique to provide several unique properties. It retains much of the oryzanol that is naturally present in the crude oil. Due to its strong antioxidant properties, oryzanol retards oil degradation at elevated temperatures. This results in oil with an extended fry-life and fried foods with improved storage stability. While Oryzan™ rice bran oil can be used alone, it can also be blended with other oils to improve their frying performance.

Properties at a Glance

  • Contributes appealing nut-like flavor
  • Consists of 80% oleic and linoleic fatty acids
  • Naturally free of trans fatty acids (TFA's)
  • Typically contains oryzanol content of 1.0%
  • Has long fry-life
  • Produces fried foods with good storage stability

Technical Data
Color (Lovibond, red) 4.5 max AOCS Cc 13b-45
Free Fatty Acid (% as oleic) 0.05 max AOCS Ca 5a-40
Peroxide Value (meq/kg) 1.0 max AOCS Cd 8-53
Moisture (%) 0.05 max AAOCS Ca 2e-84
Chlorophyll (ppb) 75 max AOCS Cc 13d-55
Cold Test (hours) 0.5 min AOCS Cc 11-53
Iodine Value (wijs) 99-108 AOCS Cd 1-25
Oryzanol (%) 1.0 min Spectrophotometric

Fatty Acid Composition
Palmitic (16:0) 15.0%
Stearic (18:0) 1.9%
Oleic (18:1) 42.5%
Linoleic (18:2) 39.1%
Linolenic (18:3) 1.1%
Arachidic (20:0) 0.5%
Behenic (22:0) 0.2%

For purchase information on Oryzan™ and other Rice Bran Oil products, contact:
Oilseeds International Ltd.
855 Sansome Street, Suite 100
San Francisco, CA 94111
Phone: (415) 956-7251
Fax: (415) 394-9023
E-mail: Sales@ricebranoil.biz

Frying Performance
Oryzan™ Rice Bran Oil Out Performs Partially Hydrogenated Soybean Oil

Study Design
In a frying study conducted at Riceland's Research & Technical Center, Oryzan™ rice bran oil was compared with partially hydrogenated soybean oil (IV = 99). The study simulated restaurant cooking conditions in which oils are subjected to continuous frying. Oil frying performance was assessed by use of a Food Oil Sensor (FOS)1, by monitoring oil free fatty acid (FFA) 2 content, and by sensory evaluation of the fried food.
French fries fried in Oryzan™ were observed to be much less greasy than those fried in partially hydrogenated soybean oil.

FOS Results

The rate of change in the FOS reading during frying was quite different for the two oils. As depicted in the graph above, the FOS reading for Oryzan™ increased steadily during the first 48 hours of frying, then slowed dramatically as frying continued. In contrast, FOS values for the hydrogenated soy oil steadily increased throughout the study.

FFA Test Results

FFA levels remained relatively low in both oils during the first 48 to 72 hours of frying and showed little change in the Oryzan™ until after 144 hours of frying. In contrast, FFA's accumulated quickly in the hydrogenated soybean oil between 72 and 168 hours of frying. The soybean oil started smoking after 64 hours of frying.

Sensory Test Results
French fries fried in Oryzan™ were observed to be much less greasy than those fried in partially hydrogenated soybean oil. They were also crispier on the outside. The Oryzan™ rice bran oil did not add extra flavor to the french fry so that true potato flavor was observed. The soybean oil developed an off-flavor that interfered in the taste of the potato.

1Food Oil Sensor (FOS). The Food Oil Sensor (FOS) is designed to test the dielectric constant of fat. As oil undergoes thermal and oxidative breakdown, its dielectric constant increases. Frying oil is typically replaced when its FOS reading reaches 5.

2Free Fatty Acids (FFA). Fatty acids represent an inherent part of the fat molecular structure. During frying, however, they are hydrolyzed from the fat to become FFA. Elevated levels of FFA cause oils to generate smoke during frying, hasten oxidative degradation, and contribute to off-flavors and excessive oil absorption by the food being fried.