In the past several years, Fusarium graminearum contamination has progressively increased in North American crops such that grain yields for barley, wheat and corn have declined substantially, and regulations have been developed to restrict the levels of the toxins in finished food products. The toxins are known to reduce feed intake and weight gain in livestock and to reduce reproductive efficiency. In the past 20 years, plant breeding programs have developed only minor improvements in resistance to either toxin or pathogen effects and so far there is no evidence that fully resistant varieties will emerge in the foreseeable future. An estimated $1 billion was lost in western Minnesota and eastern North Dakota alone during the 1990s due to Fusarium infestation. Minnesota agriculture was hit especially hard due to its reliance on the high-yielding Red River Valley production area.
Many grains, especially wheat in the US, are milled into flour. The goal of the milling process is to separate as fully as possible the bran and the germ portion of the wheat kernel from the endosperm. The endosperm is then further reduced into flour. Depending on the color of the type of grain being milled, and the end use of the flour, it may be further processed or bleached. The current process involves the oxidation of the red or yellow pigments in the flour to produce white flour. Oxidization will occur naturally, over time, with the exposure of flour to air. Historically, millers would age flour for several weeks to achieve white flour. This natural oxidation, however, was an irregular process requiring considerable time and space. Today, the bleaching process is accomplished by the use of chemical bleaching agents. Flours treated with these bleaching agents must be labeled as bleached flour.
To date, no method has been developed to treat grains or seeds to effectively aid in reducing the level of fungal contamination and concomitant toxins. Thus, there remains a continuing need for a means to effectively reduce the presence of microbial contaminants in grains and seeds. There is further a long-felt, unresolved need to minimize the presence of microbial toxins in grains and seed. There is also a need for a means to effectively bleach whole grains, rather than bleaching the milled flour. Preferably, such treatments would be environmentally safe.