A Better Spread for Your BreadBy
A better table spread for your bread could result from work with
genetically modified soybean oils now underway at
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 thats 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
arent suitable for margarines in their natural state, but after
interesterification show promise for use in soft tub margarines.
Scientific contact: Gary R. List,
Quality and Safety Research, ARS
National Center for
Agricultural Utilization Research, Peoria, Ill., phone (309)
681-6555, fax (309) 681-6679,