A Better Spread for Your Bread

A better table spread for your bread could result from work with genetically modified soybean oils now underway at Agricultural Research Service laboratories.

Consumers want a good-tasting product that comes out of the refrigerator in a solid form and spreads easily right out of the container. The challenge is meeting those requirements and finding ways to tap new soybean oils to produce a more healthful product.

New soybean varieties have been bred especially to produce higher levels of oleic acid, a mono-unsaturated fatty acid that’s been shown to be more healthful than other types of oils. This has prompted Gary R. List and colleagues at ARS’ National Center for Agricultural Utilization Research, Peoria, Ill., to examine new ways of using these oils in creating table spreads.

Food chemists use two basic techniques to make margarine: hydrogenation and interesterification. Hydrogenation chemically adds hydrogens to a chain of molecules, making a product with a higher melting point and thus the solid form of margarine. But it forms trans-fatty acids, which some studies suggest may slightly raise cholesterol levels in humans.

Interesterification rearranges the fat molecules, resulting in a product with a higher melting point without forming trans-fatty acids. Spreads made this way have the desired solid-from-the-refrigerator form without the disadvantages of hydrogenation.

The ARS scientists also are studying the table-spread potential of oils from genetically modified soybeans that contain up to 33 percent stearic acid. Stearic acid is a saturated fat that makes it possible to produce margarine without hydrogenation. The high-stearic-acid oils aren’t suitable for margarines in their natural state, but after interesterification show promise for use in soft tub margarines.

Scientific contact: Gary R. List, Food Quality and Safety Research, ARS National Center for Agricultural Utilization Research, Peoria, Ill., phone (309) 681-6555, fax (309) 681-6679, listgr@mail.ncaur.usda.gov.