An oil's smoke point determines how hot it can get before breaking down. Refined hemp oil's smoke point of approximately 205 degrees Celsius (400 degrees Fahrenheit) makes it suitable for most home cooking. Understanding the underlying chemistry helps explain why some oils handle heat better than others.
What "smoke point" actually means
The smoke point is the temperature at which an oil begins to visibly smoke when heated. Past this point, the oil's fatty acids and other compounds begin breaking down rapidly. The breakdown produces:
- Smoke (visible sign that decomposition is happening)
- Off-flavours (acrid, bitter notes that transfer to food)
- Reduced nutritional value
- Free radicals (some of which may be problematic with sustained exposure)
- Acrolein (a respiratory irritant)
Why refined oils have higher smoke points
The smoke point of an oil depends primarily on three factors:
1. Free fatty acid content
Free fatty acids smoke at lower temperatures than triglycerides. Refining removes most free fatty acids, raising the smoke point. Cold-pressed virgin oils retain free fatty acids and consequently have lower smoke points.
2. Impurities and minor compounds
Phospholipids, pigments, and small particles all begin to break down at lower temperatures than the bulk oil. Refining removes these, leaving primarily triglycerides which tolerate higher heat.
3. Fatty acid composition
More saturated fats have higher inherent smoke points than highly unsaturated fats. Refined hemp oil cannot have a higher smoke point than its fatty acid composition allows. The 80 percent polyunsaturated composition caps how high the smoke point can go even with refining.
Smoke point comparison across oils
| Oil | Smoke point | Primary saturation |
|---|---|---|
| Refined hemp oil | ~205°C / 400°F | Polyunsaturated (80%) |
| Cold-pressed hemp oil | ~165°C / 330°F | Polyunsaturated (80%) |
| Extra virgin olive oil | ~190°C / 375°F | Monounsaturated |
| Refined olive oil | ~240°C / 465°F | Monounsaturated |
| Refined avocado oil | ~270°C / 520°F | Monounsaturated |
| Refined coconut oil | ~230°C / 450°F | Saturated |
| Butter | ~150°C / 300°F | Saturated (with water content lowering smoke point) |
| Refined canola oil | ~204°C / 400°F | Polyunsaturated |
| Refined sunflower oil | ~232°C / 450°F | Polyunsaturated |
| Refined peanut oil | ~230°C / 450°F | Monounsaturated |
Practical implications
For home cooking decisions:
- Refined hemp oil works for most stovetop and oven applications under 200°C.
- For high-heat deep frying, avocado or peanut oil performs better.
- For most baking, refined hemp oil is interchangeable with refined canola or sunflower oil.
- For finishing applications, virgin hemp oil delivers more flavour.
Reading the temperature of your cooking
To stay below the smoke point in practice:
- Cold pan, oil added, gradual heat. Heat the empty pan first only when using oils with very high smoke points; otherwise add oil to a cold pan and heat gradually.
- Watch for shimmer, not smoke. Oil ready for cooking will shimmer and ripple in the pan. Smoke means it has already passed its safe temperature.
- Reduce heat when food enters. Adding cold food cools the oil; heat can usually be reduced after the initial sear.
- If oil smokes, discard. Once oil has smoked, it has degraded; using it produces off-flavours and degraded nutrition.
Smoke point is not the only consideration
Even oils with high smoke points can develop off-flavours and oxidation products before reaching their smoke point. For repeated frying applications, oils with high saturation (which resist oxidation) are often better than oils with high smoke points but high polyunsaturation. This is why coconut oil and lard, despite their flavour profiles, are sometimes preferred for deep frying.