Oil For Tuscan Fries

Our answer

Nigella's Tuscan Fries (from NIGELLISSIMA) are unusual in that the cut potatoes are put into cold oil and then the pot containing oil and potatoes is heated (as opposed to the usual process of immersing the potatoes in preheated oil). The recipe uses flavourless vegetable oil, which is the most common oil used for deep fat frying. These oils can be sourced from various plants but are usually expeller pressed and refined. The most common oils are sunflower oil, corn oil, peanut oil (often labelled as groundnut oil) and rapeseed oil (in North America usually labelled as Canola oil). Expeller pressing generates a lot of heat and the heat does cause some of the nutrients in the oils to expire.

Cold pressed oils, such as extra virgin olive oil or cold pressed rapeseed oil, are usually unrefined and tend to have a lower smoke point than refined oils. That means that they will generate smoke at temperatures lower than flavourless oils and can be unpleasant to use for high temperature frying. Some of these oils also have strong flavours, which will affect the finished taste of the food being fried. But it should also be noted that it does not seem particularly worth using cold pressed oils for high temperature frying as when they are heated the nutrients retained during cold pressing are then affected by the high heat needed for frying. We can't recommend any particular brand and don't have a preference for any particular plant oil, but would suggest that you use the best quality oil that you are able to.