Not too long ago, using the words “healthy” and “fat” in the same breath just wasn’t done. But now, the word about good fats has spread. Health-conscious consumers are working to cut back on bad fats, and they’re relying on the food industry to provide tasty options that are low in saturated fats. In turn, food-product developers are relying on healthy oils to provide the functional properties of fat in their formulations. Rice bran oil is one such product; it’s versatile, free of trans fatty acids, and it has an added bonus: antioxidants.
Vitamin E, in the form of tocopherol and tocotrienol, naturally occurs in rice bran oil. Said to protect cells against free radicals, vitamin E may help prevent certain cancers and cardiovascular disease. Further, rice bran oil contains oryzanol, a combination of sterols and ferulic acid that has been shown to reduce low-density lipoprotein, or so-called “bad” cholesterol.
In 1994, RITO, a partnership between Riceland Foods, Inc., Stuttgart, AR, and Oilseeds International, San Francisco, began commercial production of rice bran oil in the United States. Rice bran oil is similar to peanut oil in fatty-acid composition, and has a slightly higher saturation level than conventional soybean oil (approximate 2.5% of the total fatty acids higher). Oleic and linoleic fatty acids make up more than 80% of the fatty acids. Further, the low linolenic acid content of rice bran oil (1.1%) makes it more stable to oxidation than soybean oil (6.8%). Its appearance ranges from cloudy to clear, depending on the dewaxing processes applied.
Already widely used as a frying oil in Asia, rice bran oil can be used in place of vegetable oils in most applications. It has a subtle, nutlike flavor and good storage stability. It also has a good fry life, is resistant to smoking at high-frying temperatures and doesn’t require hydrogenation, according to RITO. This is largely due to the oil’s moderate level of saturated fatty acids, and partially due to its low linolenic-acid content. According to RITO, many Japanese restaurants in the United States use this oil for frying tempura and for stir-frying, as its delicate flavor does not overpower meat, seafood or vegetables. It can also be used in place of coconut oil for a popcorn oil with a lower saturated-fat content.
When processed to retain high levels of antioxidant tocopherols and tocotrienols, rice bran oil also can be used as a coating for crackers, nuts and other snacks to extend shelf life. Further, rice bran oil can be blended with less-stable oils to improve their stability in food systems. Because rice bran oil forms a stable ß' crystal lattice and it has an intermediate palmitic acid content, it provides good plasticity, creaminess and spreading properties to margarine and shortening without hydrogenation.
RITO provides the following specifications: Crude rice bran oil is composed of 81.3% to 84.3% triglycerides; 2% to 3% diglycerides; 5% to 6% monoglycerides; 2% to 3% free fatty acids; 0.3% waxes; 0.8% glycolipids; 1.6% phospholipids; and 4% unsaponifiables. Compared to some vegetable oils, crude rice bran oil has higher levels of nontriglyceride components, but most are removed during the refining process. Refined rice bran oil includes a maximum free fatty acid level (as oleic acid) of 0.1%, a maximum peroxide value of 1.0 meq per kg, 0.05% moisture, an iodine value of 99 to 108, saponification value of 180 to 195, and a Lovibond color value of 3.5R.