I know annatto is not an Indian spice, and I guess this is more of a question for Lapis, but does anyone know how long you can keep homemade annatto/achiote oil for? Some people say that it will only keep for a week, but I would have thought you could keep it for longer than that.

Sid

I'd not heard of this until now, but my good friend google says 4-5 days at room temp in an airtight container.

Steve

I read it will keep comfortably in the 'fridge for at least a week. After that you can continue to use it for several months but the flavour will deteriorate, so it is better made in small batches.

"You learn something every day" - I didn't know that annatto was used to colour some western cheeses!

Thanks :) I had read that it could be stored for a week at room temperature, but I assumed that it could be stored for much longer than that, lets say if it was in a dark place.

Sid

I have some annatto seeds, and they are tasteless. I am not aware that they provide an oil. They are used for colour, of course, and added to Red Leicester cheese, I believe. I assume the oil is not from annatto seeds, but just coloured by it. In that case, it would depend on the type of oil used.

Breakdown of oil is proportional to the degree of unsaturation they have, so walnut and linseed oil, although an excellent source of omega 3 and 6, will go off rather quickly, depending on how much air they are exposed to.

Ah, okay. What I meant by annatto oil is the oil you can colour by frying annatto seeds until the oil changes colour, not annatto seed oil. Funny thing is, I have made small batches of it in the past, as and when it is needed, but it doesn't have the same taste as the seeds. The oil has a slight perfume smell to it, but as for taste then I don't think there is one. If the seeds are reasonably fresh then they have a nice flavour to them. I use them to make rojo paste for Mexican cooking (which I do very seldom).

Sid.

OK Sid, I understand now.

What you have done is an oil extraction, where flavour ( and colour) chemicals are extracted into the oil. The amount extracted depends on many things, not least how 'oil-liking' the chemical is. Some spices have just one or two flavour chemicals, like cloves, whereas others have many, like black pepper. All the chemicals will dissolve in the oil to a greater or lesser extent. And the profile may change, as to give a different flavour.

Most flavour chemicals in spices are quite oil soluble, so it may make little difference, and underlines the importance of this phenomenon in cooking, Indian in particular.

As far as annatto oil is concerned, the only thing that will affect the oxidation of it is if it has extracted any anti-oxidants. This will slow the degradation of the oil, lessening the formation of free radicals, and auto-oxidation.