By Dr. McKenzie Nisbet, ND

Cooking Oils: The Best Oils and When to Use Them

COOKING OILS:

The Best Oils and When to Use Them

 

There are many cooking oils out there to choose from. So many in fact that it may just feel easier to keep using that classic ‘vegetable oil’ you’re accustom to. But we use oil while preparing meals almost daily and I strongly believe you should know (and feel good about) what you are putting in your body. This post will help you make informed decisions while cooking with oils.

So how do you choose the right oil? Choosing the right oil depends on a few different factors: What it is, how it’s made, how it’s stored and how much heat it can handle. This last point is especially important, because most of us are cooking oils at temperatures that are far to high. We will address all four factors here.

 

THE TYPE OF OIL

The type of your cooking oil lays the groundwork for how good it is for you. To keep it simple, there are two main types of omega fatty acids: 3 and 6. Omega 3 is anti-inflammatory, and has a positive impact on heart disease, diabetes, autoimmune conditions, mood disorders and much more. Historically the human diet was approximately a 1:1 ratio of Omega 6 to Omega 3. Today it is roughly 16:1 – so we have a lot more omega 6 relative to omega 3 oils in our daily diet. This is why adding extra omega 3 rich foods to your diet helps bring down inflammation – it shifts the ratio in the right direction.

GOAL: Aim for oils high in omega 3 (relative to omega 6). Note: many oils that have a good omega ratio can’t be cooked at a high temperature, such as flaxseed oil. Try adding these healthy oils to salads instead. This way you get the anti-inflammatory effect of the oil without the harmful effects of free radicals (formed during overheating).

 

HOW THE OIL IS MADE

Oils can change substantially when exposed to extreme methods of preparation. Avoid oils exposed to hydrogenation (partial/full), chemical extraction (such as hexane), refining, deodorization, and decolourization. You want to look for oils that are as close to their natural state as possible. Also look for oils that are organic and non-GMO so you minimize your exposure to the effects of harmful farming practices.

GOAL: You should aim for oils that are cold pressed, or unrefined. Look at the label for phrases like “Non-GMO Cold-Pressed Organic Coconut Oil” to ensure it is checking all the boxes.

Note: Cold Pressed vs. Expeller Pressed

When you are checking oil labels you may come across the term “expeller pressed”. This is a method used to extract oil by essentially just pressing the oil source without any added chemicals or heat. Some heat is created in this process from the friction, which may affect more delicate oils. “Cold pressed” is similar to this method, except the environment is kept below a certain temperature to preserve more temperature-sensitive oils (such as flaxseed oil).

 

HOW THE OIL IS STORED

Oils can become rancid when stored in an environment where they are exposed to oxygen or light. The free radicals released from the oil during exposure to these environments can harm the body.

GOAL: You should always store your oils in a cool, dry location, away from direct light. Also be sure to screw the cap on tight to reduce exposure to oxygen.

 

HOW MUCH HEAT THE OIL CAN HANDLE (SMOKE POINT)

Every oil starts to smoke as it reaches a certain temperature. When the temperature passes this “smoke point” the structure of the oil molecules change (denature) and the oil gets oxidized. Free radicals are then released which are harmful to your body.

What affects the oils smoke point? Many factors affect the smoke point of oils, but here are a couple of tricks to help understand what is happening when an oil is heated.

1.Refined vs unrefined

  • Oils that are more refined have a higher smoke point. This is because factors such as vitamins and nutrients (that would be damaged at high temperatures) have been removed.

2. Saturated vs Unsaturated

  • The more saturated a fat is the more tight the fatty acids within that oil are bound. The tighter the structure, the harder for it to break apart – therefore a higher smoke point. That is why oils such as avocado and coconut oil have higher smoke points.
  • On the other side of the spectrum are polyunsaturated fats. These are less tightly bound and therefore smoke at a lower temperature. These include unrefined sunflower and safflower oil.

GOAL: Pick healthy oils based on what temperature you are preparing your food at and the smoke point of the oil.

Use the guide below to help make the right choice.

Note: Smoke points may vary based on what source you use. This is because the oils themselves are not always created in the exact same environment. A slight variation in the ratio of compounds within the oil will affect it’s temperature threshold. For example, one source may have almond oil at 420°F and another at 430°F.

Cooking Heat Break Down:

  • High Heat
    • Pan frying, sautéing, grilling, pan roasting, searing, stir-frying, broiling, and caramelization
    • Try: Avocado oil, Coconut oil, or Clarified butter (ghee)
  • Medium Heat
    • Gentle sauté, stewing, baking (less than 300°F), braising
    • Try: All of the above, butter, or olive oil
  • Low/No Heat
    • Add the oil after the food has been removed from the heat source, or use in raw dishes
    • Try: All of the above, or unrefined nut and seed oil to boost the omega 3 content of your meal

MY FAVOURITE OILS

Avocado Oil

  • Smoke Point: 520°F (271°C)
  • Used For: Low/Medium/High Heat Cooking
  • Label Check: “cold-pressed” and “organic”

Ghee

  • Smoke Point: 485°F (252°C)
  • Used For: Low/Medium/High Heat Cooking
  • Label Check: “grass fed” and “organic”

Coconut Oil

  • Smoke Point: 350°F (177°C)
  • Used For: Low/Medium/High Heat Cooking
  • Label Check: “cold-pressed”, “organic” and “virgin”

Butter

  • Smoke Point: 350°F (177°C)
  • Used For: Low/Medium Heat Cooking
  • Label Check: “grass fed” and “organic”

Extra Virgin Olive Oil

  • Smoke Point: 320°F (160°C)
  • Used For: Low/Medium Heat Cooking
  • Label Check: “cold-pressed” and “organic”

Note: olive oil is unique due to a number of protective compounds it contains. When heated to the same temperature as other similar oils it produces less volatile aldehydes (harmful fumes). If you choose to cook with olive oil keep the time short and the temperature low, or try out one of the other options above.

 

Happy cooking!

 

 

Resources:

Fullana, A. (2004, Aug 11). Comparison of volatile aldehydes present in the cooking fumes of extra virgin olive, olive, and canola oils. https://www.ncbi.nlm.nih.gov/pubmed/15291498

Good, J. (2012 Apr 17). Smoke Point of Oils for Heathy Cooking. https://jonbarron.org/diet-and-nutrition/healthiest-cooking-oil-chart-smoke-points

Guillen, MD. (2012 Sept 1). Study by 1H NMR spectroscopy of the evolution of extra virgin olive oil composition submitted to frying temperature in an industrial fryer for a prolonged period of time. http://www.sciencedirect.com/science/article/pii/S0308814612002713

Kamsiah, J. (2011, Dec). The effects of heated vegetable oils on blood pressure in rats. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3226610/ 

Melina, V. The Vegetarian Health Institute. https://www.veghealth.com/nutrition-tables/Smoke-Points-of-Oils-table.pdf

Simopoulos, AP. (2002 Oct). The importance of the ratio of omega-6/omega-3 essential fatty acids. https://www.ncbi.nlm.nih.gov/pubmed/12442909