Shijing said:
			
		
	
	
		
		
			
	
		
			
				Mrs. Peel said:
			
		
	
	
		
		
			Should I go back to using oilve oil to cook my food with for a while and lay off the bacon?  I never used to eat it very often before.
		
		
	 
I'm pretty sure that olive oil is supposed to be used "cold" only, since it breaks down in the wrong ways when heated -- my understanding is that grapeseed oil is a better substitute (I use my recycled bacon grease for cooking most of the time, but I have a bottle of grapeseed oil on hand that I use occasionally).
		
 
		
	 
Here's the smoke point of different oils :
from http://en.wikipedia.org/wiki/Smoke_point
	
	
		
		
			The smoke point generally refers to the temperature at which a cooking fat or oil begins to break down to glycerol and free fatty acids. The glycerol is then further broken down to acrolein which is a component of the bluish smoke. It is the presence of the acrolein that causes the smoke to be extremely irritating to the eyes and throat. The smoke point also marks the beginning of both flavor and nutritional degradation. Therefore, it is a key consideration when selecting a fat for frying, with the smoke point of the specific oil dictating its maximum usable temperature and therefore its possible applications. For instance, since deep frying is a very high temperature process, it requires a fat with a high smoke point.
Considerably above the temperature of the smoke point is the flash point, the point at which the vapors from the oil can first ignite when mixed with air.
		
		
	 
Fat   Quality    Smoke Point 
Almond oil    420°F   216°C 
Avocado oil    520°F 271°C 
Butter    350°F 177°C 
Canola oil Expeller Press   464°F 240°C 
Canola oil High Oleic   475°F 246°C 
Canola oil Refined   470°F 240°C 
Coconut oil Unrefined    350°F 177°C 
Coconut oil Refined    450°F 232°C 
Corn oil Unrefined    320°F 160°C 
Corn oil Refined    450°F 232°C 
Cottonseed oil     420°F 216°C 
Flax seed oil Unrefined    225°F 107°C 
Ghee (Indian Clarified Butter)     485°F 252°C  
Grapeseed oil     420°F 216°C   Hazelnut oil     430°F 221°C 
Hemp oil     330°F 165°C 
Lard     370°F 188°C 
Macadamia oil     413°F 210°C 
Olive oil Extra virgin   375°F 191°C 
Olive oil Virgin    420°F 216°C 
Olive oil Pomace    460°F 238°C 
Olive oil Extra light    468°F 242°C 
Olive oil, high quality (low acidity) Extra virgin    405°F 207°C  Palm oil Difractionated    455°F 235°C[1] 
Peanut oil Unrefined    320°F 160°C 
Peanut oil Refined    450°F 232°C 
Rice bran oil     490°F 254°C 
Safflower oil Unrefined    225°F 107°C 
Safflower oil Semirefined    320°F 160°C 
Safflower oil Refined    510°F 266°C 
Sesame oil Unrefined    350°F 177°C 
Sesame oil Semirefined    450°F 232°C 
Soybean oil Unrefined    320°F 160°C 
Soybean oil Semirefined    350°F 177°C 
Soybean oil Refined    450°F 232°C 
Sunflower oil Unrefined    225°F 107°C 
Sunflower oil Semirefined    450°F 232°C 
Sunflower oil, high oleic Unrefined    320°F 160°C 
Sunflower oil Refined    450°F 232°C 
Tea seed oil     485°F 252°C 
Vegetable shortening     360°F 182°C 
Walnut oil Unrefined    320°F 160°C 
Walnut oil Semirefined    400°F 204°C