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Chemical Process Creates Food Source from Plant Waste

Plants that are not traditionally thought of as food crops can become an important source of nutrients, thanks to a process that converts cellulose in the plants' cell walls into a starch that provides dietary fiber. Starch makes up 20 to 40 percent of our daily caloric intake, and a significant new source could help feed our increasingly populous and hungry world.

The process was developed by Y. H. Percival Zhang and a team from Virginia Tech. It uses an enzyme to break up cellulose at the molecular level, and reconfigure it as a starch. It does not require expensive equipment, heat, or chemical reagents, and does not generate any waste. Plant waste material, such as the stem, leaves and husk of corn, is completely transformed. Thirty percent is converted to starch, and the remainder becomes glucose that can be used to produce ethanol.

Zhang says the 'biotransformation' process would allow food to be created from any plant, reducing the need to grow crops on valuable land that requires fertilizers, pesticides, and large amounts of water. In addition, the starch could be used to manufacture edible, clear films for food packaging.

The cellulose-to-starch conversion process is detailed in The Proceedings of the National Academy of Sciences.

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