Oils

Cooking oil or finishing oil

This is the distinction that matters most. A cooking oil is chosen for its smoke point and its neutrality: it gets hot without breaking down and it stays out of the way. A finishing oil is chosen for flavour, and heat destroys exactly what you paid for, so it goes on at the end or at the table. Extra virgin olive oil, roasted nut oils and chili oils all belong in the second group.

Smoke point, briefly

The smoke point is where an oil starts to break down and taste burnt. Refined oils sit high because refining removes the particles that scorch. Unrefined oils sit lower because the things that give them flavour are the same things that burn. Searing and frying want the high end; dressings and drizzling want the low.

What agrumato means

Some flavoured olive oils are made by crushing whole lemons, basil or chilies together with the olives at the mill, rather than infusing finished oil with an extract afterwards. It takes far more fruit and it is why the result tastes of the thing itself instead of tasting of flavouring.

Storing oil

Light and heat are what turn oil rancid, which is why good producers use opaque bottles and tins rather than clear glass. Keep it in a cupboard rather than next to the hob, close it properly, and treat an opened bottle as something to finish within a few months. Nut oils are the most fragile of the lot.