Stretching Fat with Starch

Article excerpt

Blasting starch and oil with a steam jet yields a unique material with potential applications ranging from ice cream to coatings, hand lotions, and plywood adhesives.

What if ...? As our minds are exposed to new ideas, materials, and information, occasionally we conceive of something radically different from anything else and wonder if it could be made. So it was that one of us, Kenneth Eskins, began to wonder some five years ago: What if I could make a synthetic cell and place in its membrane exactly the enzymes needed to make useful products? Furthermore, why shouldn't it be possible to make the cell membrane out of starch, a readily available agricultural product, instead of the rather specifically modified forms of fatty acids that comprise the membranes of most living cells?

Although research of this type had never been published, no one had proved that it couldn't be done. To tackle the project, Eskins, a chemist in the National Center for Agricultural Utilization Research (NCAUR) of the USDA's Agricultural Research Service in Peoria, Illinois, teamed up with another of us, George Fanta, who is an experienced carbohydrate chemist at NCAUR.

Their idea was to mix oil and starch "intimately" enough for individual starch molecules to interact with minute oil droplets. To achieve this, starch granules, which do not dissolve easily in water, would first need to be fully dissolved in it, so that the individual starch molecules would be uniformly distributed throughout the water. Then the oil would need to be broken into fine particles and mixed with the starch solution.

Fortunately, a technology that seemed likely to meet these two objectives was readily available in the steam jet cooker. By co-cooking starch and oil in the steam jet cooker, they reasoned, associations might form that could lead to membrane precursors.

To their surprise, they inadvertently discovered instead a kind of material that had never been seen before--one that was to evolve rapidly into an exciting new technology for transforming starch and oil into new products. The starch-oil composite formed in the steam jet cooker--tiny oil droplets surrounded by a film of starch and suspended in the greater body of starch--had remarkable stability and many unique properties, which will be discussed later. These products and the process for forming them have been granted the trademark Fantesk, one of only two trademarks owned by the USDA.

When the third of the authors, NCAUR plant physiologist Frederick Felker, joined the Fantesk team, he brought valuable expertise in microscopy, which was needed for characterizing the structure of the new materials. Felker determined the size and uniformity of the oil droplets formed under different cooking conditions. He also identified an oil-starch boundary layer that seems to be a key factor in giving Fantesk products their stability and other desirable properties.

What started out as one man's vision of a new artificial membrane system has evolved, with group effort, into the Fantesk process and family of products. Starting from the innovative idea of creating intimate mixtures of starch and oil, we have defined a broad type of process that is environmentally friendly and uses readily available agricultural products as starting materials.

The diverse Fantesk products, each with the characteristic array of oil microdroplets encapsulated in starch, are themselves environmentally friendly and may find uses in products ranging from ice cream to hand lotion, face powder, popcorn, printer's ink, and plywood adhesives. The Fantesk process and products promise to generate new markets for major agricultural products and also to open a new scientific frontier: the study of the interactions of starch and oil on a molecular level.

Making the flakes

Cornstarch and soybean oil are among the highest-volume products of American agriculture, and an ever-increasing range of food and industrial applications is being developed for each of these. …