Bakers Journal

Features Technical
Technical Talk: August September 2011


August 18, 2011
By Dr. John Michaelides

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GMOs have gained  a bad rap, but they may be the secret to improving food safety

GMOs have gained  a bad rap, but they may be the secret to improving food safety

We may not know it, but one or more of the ingredients in many of the foods we eat may be sourced from genetically modified organisms (GMOs). These ingredients are processed from seeds, grains or other parts of plants, or are derived from animals or micro-organisms that have been altered through genetic manipulation.

Classical genetics was based on the work of many great scientists such as Charles Darwin and Gregor Mendel, who discovered hybridization between plants and established the laws governing heredity, or how traits are passed on from generation to generation. These discoveries led to the development of classical breeding techniques that gave us the crops of the industrial revolution, and we have been growing them ever since. Genetic manipulation allowed us to breed many new varieties of wheat, barley, oats, corn and rice, among other crops. These varieties can produce greater yields, be resistant to diseases or offer higher proportions of components such as protein, oil or starch.

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Developing new varieties using classical breeding techniques is, however, a long and tedious procedure and often random rather than specific. But with today’s scientific advancements, we are witnessing the second wave of the agricultural revolution.
 
This next generation transfers traits more efficiently and develops new varieties through genetic engineering. This engineering is based on James Watson and Francis Crick’s discovery of DNA in the 1950s. The scientific advances that followed have allowed us to transfer DNA material from one species to another, transferring traits from the donor to the recipient species. Enzymes are used to cut and paste certain sequences of DNA and splice them together to develop recombinant DNA (or rDNA) in test tubes. Genetic engineering then transfers rDNA from one organism into another. Today, new technologies and tools allow us to carry out these manipulations more effectively.

The first genetically modified crop developed was the soybean. In 1988, soybeans resistant to the herbicide glyphosate were developed, creating glyphosate-tolerant soybeans. Other genetic modifications to soybeans include nutritional enhancements, such as a gene from the Brazil nut that enables a soybean to produce a higher amount of the amino acid methionine. To date, this variety has not been commercialized due to concern that the allergenic protein from the nut may be transferred to the soybean. Still, more than 70 per cent of the soybeans grown around the world are genetically modified in some way.

The other major crop to undergo genetic modification is corn. Genes that enable the plant to produce the Bacillus thuringensis (Bt) protein, which is toxic to insects and certain pests have been added to corn. In the 1990s, this was commercialized in StarLink corn; however, due to regulatory uncertainties surrounding the protein, the StarLink variety has only been approved for use in animal feed. Another Bt corn was developed by DuPont’s Pioneer Hi-Bred International. This variety did not face any regulatory issues and has been approved for use in Canada and the United States.

Developing genetically modified crops has often focused on developing resistance to micro-organisms and fungi. Major research efforts are directed towards resistance to Fusarium infection, which would eliminate vomitoxin and other mycotoxins from wheat flour supplies. Other research efforts to enhance the safety of grains include the introduction of genes to reduce accumulation of toxic heavy metals such as cadmium in durum wheat.

The introduction of genetically modified wheat in North America was planned for 2004; however, the application for approval was withdrawn prior to approval. Because both Canada and the United States are major exporters of wheat, introducing this variety will limit available export markets. This would have grave economic implications for both countries.

At present, no commercially grown genetically modified wheat is available in Canada. Australia has allowed field testing of a wheat variety modified to be tolerant to drought. The only genetically modified cereals commercially produced are corn and rice. Neither is used for baking in Europe; however, many secondary ingredients are produced from these cereals.

These crops are very important, given the food supply problems facing many parts of the world. Diverting grains towards biofuels, combined with climate change, is resulting in ingredient and food shortages. In turn, this causes the prices of commodity crops and other foods to rise. Projected population growth in the coming years will exert further pressure on the food supply.

The possibilities for enhancing production of cereals and other crops through genetic engineering are endless. Many ingredients used in the baking industry may originate from GMOs. These ingredients can range from flours, proteins, starches and oils, to ingredients such as emulsifiers, gums and enzymes. Determining if an ingredient is produced from a genetically modified organism is very difficult and testing can be very costly.

Although many are skeptical about its safety implications, genetic engineering provides us with powerful tools to address some of the emerging challenges facing the agriculture and the food supply. GMOs may just be the next agricultural revolution. / BJ


Dr. John Michaelides is an independent food industry consultant to the Guelph Food Technology Centre (GFTC). For more information, or fee-for-service help with product or process development needs, please contact him at 519-821-1246 ext. 5052, by fax at 519-836-1281, by e-mail at jmichaelides@gftc.ca or j.jmichaelides@gmail.com.


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