Ethanol leftover could be used in bread, claims US researcher

Sowmya Arra, a food science graduate student at South Dakota State University (SDSU), won the poster competition at the Institute of Food Technologists (IFT) conference in California for her master’s thesis which studied the use of dried distillers grain (DDG) in chapathi bread making.

When ethanol is distilled from corn to use as a fuel additive, it leaves as a residue dried distiller’s grain and according to Arra, her research results show that post processed DDG resembles wheat flour and could eventually be processed into a low-cost flour rich in fibre and protein for use in baked goods.

Arra had to create a process of heating, vacuum chamber treatment, grinding and sterilization to produce the DDG flour.

In order to blend with another flour, the DDG flour has to be made aroma neutral, taste neutral and texture neutral, according to Arra’s advisor, Padmanaban Krishnan.

He claims that currently only about 7 to 20 per cent of the DDG flour can be combined with the traditional flour used in bread products. Adding any more of the DDG flour, particularly in yeast-leavened products, undermines the dough system, he added.

Mixed in at the right levels however, the DDG flour will add significantly to the fibre and protein of tortillas, cookies, noodles and breads, continued Krishnan.

The research work on DDG at SDSU has been part funded by the US Agricultural Research Service, as well as the South Dakota Wheat Commission and the South Dakota Corn Utilization Council.

Interest from industry to scale up the development of DDG flour is currently being sought by the researchers in order to help determine an optimal particle size, colour, protein/fibre composition, and increased shelf life for use in cereal and legume-based products as well as the optimal substitution levels in baked products and ready-to-eat (RTE) processed breakfast cereals.