Can I use cold pressed rapeseed oil for baking? Or will useful nutrients be destroyed / altered in a harmful way during the heating process?
The heat stability of an oil varies between different oils and is indicated by the ‘smoke point’. A smoke point is the temperature limit up to which it can be used safely before the oil starts to degrade. Read more about smoke points here. Smoke points are generally used in the context of more intense cooking methods such as frying where the oil serves as a medium to transfer heat. Oil or fats used in baking are part of a food matrix so the oil is not exposed to the same intense heating methods as frying, and therefore the chemical structure, including the omega 3 fatty acid content, is unlikely to be effected in the same way. Cold pressed oils tend to have a lower smoke point than refined versions so may not be typically suitable for frying but may be possible to use in baking, adding flavour and colour. For example, butter has a lower smoke point and is used in baking successfully.