Cooking Oil and Climate Change

That order of french fries with a lunchtime hotdog is just one of thousands of daily uses of cooking oil in Canada. What most people don't know, however, is that conventional methods for extracting oil from plant materials require enormous amounts of energy, which in turn produce significant greenhouse gas emissions. These methods also use large quantities of the solvent hexane, which, when released to the environment, degrades to produce greenhouse gases that contribute to climate change.

Scientists from Environment Canada's Environmental Technology Centre in Ottawa are working with CanAmera Foods and BC Research to increase the efficiency of the oil extraction process, and to reduce energy usage and greenhouse gas emissions. The three are undertaking a demonstration project to test the use of Environment Canada's patented Microwave-Assisted Process^TM in extracting cooking oil from canola.

Canola was chosen not only because it is an integral part of Canada's economically important cooking oil industry, but also because current canola oil extraction methods are expensive and require large amounts of hexane. Hexane is not yet accounted for in Canada's greenhouse gas inventory, because its degradation in the environment is complex and not fully understood. It is known, however, that its initial degradation includes the rapid release to the atmosphere of carbon dioxide--a primary greenhouse gas.

Canola flakes in hexane going through a processing system.

The MAP* technology requires less energy than conventional extraction methods because it uses microwaves to rapidly heat specific components of liquid and solid materials. It has already found extensive use in the laboratory to determine the nature and quantity of contaminants in drinking water samples, and to evaluate petroleum hydrocarbon contamination in plant material and soils. Since applying MAP* to large-scale use in the food processing industry would require complex retrofitting and a significant investment in equipment, the technology will need to prove itself at least as efficient as current methods in order to be considered for broader applications in the future.

The demonstration phase of the project will involve producing around one tonne of canola oil per hour, but the ultimate goal will be to model the current production of 800 tonnes per day at CanAmera Foods' smallest facility, located in Hamilton, Ontario. In phase two of the project, testing will be done to substitute a liquefied gas, such as propane or butane, for hexane, in the hopes of limiting or eliminating hexane use in the canola oil production industry. Tests will also be performed to determine the feasibility of using MAP* technology on other feedstock of importance to Canada, such as soya, rapeseed and flax.

Although the energy the food industry could save by using this new technology cannot be accurately determined until data are available on the level of application, a conservative estimate is that MAP* would reduce energy requirements by at least 50 per cent. A number of private-sector companies in various parts of the world are interested in the outcome of the project, such as South Korea and China for use in rice-bran processing, Malaysia and Colombia for palm oil, Pakistan and India for rapeseed and soya, and various others for cocoa. If the test results are as expected, the technology could be transferred to other countries to help reduce their energy consumption and the greenhouse gas emissions that contribute to climate change.

  Home |  Air |  Atmospheric Science |  Climate Change |  Environmental Action |  Habitat |  Pollution |  Species at Risk |  Technology |  Water |  Weather |  Wildlife