Canola Oil Properties and Uses
Canola oil is preferred by food professionals and processors because of its nutritional profile and high smoke point. canola oil has become even more valuable with high-oleic varieties that reduce the need for hydrogenation.
Cooking Facts: What happens when canola oil hits the pan?
Canola oil is the healthiest of all commonly used cooking oils. It is lowest in saturated fat, high in cholesterol-lowering mono-unsaturated fat and the best source of omega-3 fats of all popular oils. It is also highly versatile and suitable for use in salads, baking, stir-frying and deep-frying.
That’s canola oil in the bottle. What happens when canola oil hits the pan? To find out, the Canola Council challenged food chemists at the University of Lethbridge to assess the effects of common cooking practices on the stability of canola oil that consumers buy at the grocery store.
Does canola oil stand up to stove-stress or does it break down into trans fats? Here’s what they found.
Canola Bakes
Cookies with a recommended 15 minute cook time and a quick bread with a 50 minute cook time were baked at normal temperatures and high temperatures. Both cookies and quick bread turned out perfectly at normal moderate oven temperatures and burned at high temperatures. Then the scientists looked inside. For both baked goods, researchers concluded that baking temperatures do not affect the unsaturated fatty acids in canola or result in the development of trans fatty acids.
And Stir-Fries
To test the effect of different temperatures during stir-frying, a typical chicken and vegetable stir-fry was prepared using two different methods. To represent typical consumer-kitchen stir-frying, canola oil was placed in a wok and heated to 195°C and allowed to sit for 5 minutes. To represent extreme conditions, canola oil was placed in a wok, heated to the point where it was smoking (250°C) and held for 5 minutes.
For both stir-frying methods, there was no significant development of trans fatty acids. The researchers did discover however, that heating canola oil to its smoke point can reduce the amount of polyunsaturated fatty acids (linoleic and linolenic acids) due to oxidative degradation. Cooking in smoking oil is certainly not recommended, nor is it a common cooking practice in North America.
And Deep-Fries!
The researchers then decided to kick their testing up a knotch by replicating commercial rather than home deep-frying methods. During deep-frying in commercial operations, oils are used for much longer periods of time than stir-frying and baking.
For this study, a standard frying temperature of 185°C and an extreme temperature of 225° C were tested. The researchers discovered that at the standard temperature, there was negligible development of trans fatty acids and only slight loss of linolenic acid. At the extreme temperature, after eight hours a day for seven days, trans fatty acid levels rose slightly. At this point, the oil was significantly degraded and would in common commercial practice have been discarded well before this time.
The study also showed that at standard deep-frying temperatures, there was negligible loss in linolenic acid or increase in trans fatty acids even after the oil reached the point at which it would be discarded due to loss of quality.
In the home kitchen, deep-frying oil would be used for short periods at standard temperatures no more than two or three times. Given the results of the University of Lethbridge research, consumers can be confident that filtering, storing and reusing canola oil for deep-frying at home is a safe practice.
Canola Oil Performs
Overall, canola oil performs very well in all types of cooking practices, even those which use high heat for long periods of time. The University of Lethbridge trials clearly show that canola oil is a healthy choice anytime.
