Oats’ Heart-Friendly Beta Glucans Mimic Fat

For centuries, oats have been valued for the grain’s medicinal qualities. As early as 400 BC ground oat was used on skin for drying and healing, and 17th-century New World immigrants used the grain to relieve stomach aches and other ailments. At the turn of the 20th century, several mills established the Quaker Oats Company and the cereal was a favored porridge until the 1950s, when oat production started to decline. In the late 1980s, studies revealing oat bran’s heart-healthy attributes increased consumer demand for ready-to- eat oat breakfast foods and snacks. However, oats have never achieved major crop status or been profitable to grow in the United States. That could change with a new focus on oats’ valuable components – especially beta glucans – that may help prevent heart disease and certain cancers.

Production notes:

About 15 species of oats are grown in cooler regions of the world – primarily Russia, Canada, the United States, Finland, Sweden, Germany and Poland. Worldwide production has declined over the past 50 years. Russia produced 9.4 million tons in 1998 but only 4.5 million in 2000. Only Canada showed growth in the 1990s, with a record high 5.9 million tons in 1999. That is because Canada leads foreign sales – with 60 percent of the export market. The U.S. imports 1.7 million tons annually, primarily from Canada.

The United States produces mostly spring oats grown in north-central states. Minnesota leads the nation in spring oat production, followed by Wisconsin and North Dakota. In 2001, Minnesota produced 12.6 million bushels of oats valued at $17.6 million.

Oats have not been a profitable crop; input costs generally exceed revenues. However, oat varieties are being developed with improved yields, higher protein content and stronger resistance to rust, disease and insects.

Oats contain 70 to 75 percent groat, which is milled into steel-cut oats, rolled flakes, instant flakes, flour and bran. The remaining hull is waste, but can be burned for energy.

Some hulless groats are being grown under contract for specific markets. “Naked oats” have a loose hull, which is blown away during combining. The crude protein, oil and energy content of the hulless variety is much higher than regular oats and shipping and storage costs are lower. So it is well suited for some specialty food markets. However, yields are lower and because the skin coat is thinner, the oats can be damaged during combining, leading to rancidity problems in storage and reduced shelf life.

About 90 percent of U.S. oats are grown for livestock feed, as the grain is high in protein, fat and fiber. Food oats are used primarily in hot and ready-to-eat cereals, and some in granolas, cookies, breads and other cereal products. Oats have excellent moisture- holding qualities that keep baked goods fresh. But they contain little gluten so they must be blended with high-gluten flours such as wheat to make yeast breads.

Functional values:

Oats are valued for their beta-glucans, or soluble dietary fiber, which mimics fat as it gels at room temperature and liquefies during cooking. Products that contain at least 0.75 grams of beta-glucan per serving may use the FDA health claim:”Soluble fiber from foods such as oats, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease.”

Soluble fiber is believed to help reduce total serum LDL cholesterol, blood pressure and help Type II diabetics by slowing blood glucose response after meals. Tocotrienols, Vitamin E compounds in oats, may also lower serum cholesterol

The insoluble fibers in oats have a laxative effect. The fibers may help prevent gastrointestinal disorders and protect against colon cancer by diluting carcinogens in the gastrointestinal tract. Phytoestrogens in whole-grain oats may help prevent breast cancer and other hormone- related cancers.

Oat flour contains antioxidants that prevent fat-containing foods such as peanut butter, margarine, chocolate and doughnuts from going rancid. Oat flour also stabilizes fat in ice cream and other dairy products. Once reconstituted with water, oat flour forms a gel that can be used in salad dressings, gravies, dips, soups, coatings and drink mixes. Gels can also replace fat in baked products.

Industrial applications include using oat flour as a preservative inner coating in paper-bag packages for salted nuts, coffee and potato chips. Furfural, derived from oat hulls, is used in solvents and resins

Areas of opportunity:

Beta-glucan concentrate: De-fatted oat bran can be finely ground and fractionated to make a product with 50 percent more beta-glucans than regular oat bran. The concentrate could be added to food as a nutraceutical ingredient. Nurture, Inc. has introduced OatVantage™, an oat-based ingredient that manufacturers can use in foods, beverages and supplements to make the FDA heart health claim; only 1.5 grams delivers 0.75 grams of beta-glucan.

Fat replacers: OTRIM and Z-TRIM fat replacement products made from oat fractions have been developed by scientists from the USDA National Center for Agricultural Utilization Research in Peoria, Illinois.

Food applications: Soluble fiber is used to give products a fat-like texture, such as a whipped oat dessert, similar to ice cream. Oats are also used in salad dressings, sauce thickeners, ice-cream coatings and stabilizers, baby foods, beverages, baked goods and snack foods.

Oat starch: After beta-glucans are extracted, the small-granule starch that remains could be used in spoonable dairy products or cereals and snacks. Oat starch is slow to crystallize, so it is stable from freeze to thaw and holds up well under high temperatures and low pH conditions.

Oils: Next to corn, oats have the highest concentration of oil – about 6 percent. Crude oat oil contains a very high level of antioxidants, more than every major oilseed, grain or grain byproduct except wheat germ. Oat oil is rich in phospholipids and glycolipids, also called polar lipids, and are free of trans fatty acids. Breeders are working to design oats with even higher concentrations of oleic and linoleic fatty acids.

Hulless oats: A new high-fiber, high-protein pasta is being developed in Italy using a 60:40 blend of durum wheat and hulless oat flour, which is higher in protein.

Note: Some of the information in this report comes from the North American Millers Association Web site: namamillers.org

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