Cold-Pressed

There are three broad ways to get oil out of a seed: press it mechanically, press it and then apply heat to raise the yield, or extract it with a solvent, which gives the most oil and is the industrial default. Cold pressing is the first, and the claim is that no heat was added beyond what pressing generates by itself.

What that buys is the part of an oil that heat and refining take away — more of the tocopherols and sterols, more colour, more of the plant's own smell. What it costs is stability and consistency. An oil with more of its minor components intact also has more in it that can change, and a cold-pressed batch varies more from harvest to harvest than a refined one does.

The phrase is weakly defined. There is no universal temperature threshold behind it, and how it may be used on a label is decided locally, so it describes an intention more reliably than a process. It also says nothing about the two things that matter most for an oil already on a shelf: how fresh it is and how it has been kept.

None of which makes refined oils inferior. A pale, deodorised, steady oil is exactly right where the oil is a carrier and its smell would be a problem, and plenty of formulas want no plant character at all. Cold-pressed is a trade rather than a tier.