I have several recipes that call for saffron. Obviously, they all say to put the saffron in some water to extract the flavour so it spreads more evenly in the dish. However, there is no mention of the temperature of the water.
Should this be boiling water? Cold water? hot, or warm water? I know that hotter water will cause the extraction to be faster, but will there be any damage to the saffron and its flavour?
It's not unlike coffee or tea in that regard. You want a temp around 92 - 96C (197.6 - 204.8F) for the amount of time the saffron has in contact with the water. Once you have the desired flavor strength, strain it and set it aside.
It's also very forgiving. If the water is hot enough to make a cup of tea or coffee, it's fine. Saffron won't get bitter unless you actually burn it, which you're not likely to do in water. It's a king of spices for a reason - it has a very unique flavor and it is extremely easy to work with.
The more color it takes on while steeping, the stronger the flavor. You might want a little, a lot, or somewhere in the middle. The real trick is knowing when to strain it and set it aside. Treat it like anything else that is cooking and pay attention to its progress. Saffron can easily overpower other flavors that you wanted to bring out in a dish, especially with seafood.
Sometimes, you might want to just dump the whole concentration in, saffron included - depending on how you're using it. You can also make a cup or two of it at a time and freeze / refrigerate it to save some time.
From personal experience, I did not know how to cook with Saffron. So, I would soak it in a little bit of cold milk before adding it to my dessert and it never brought enough flavour or colour into my dessert. Then I started to infuse saffron in a small amount of warm water or milk, for approximately 15 to 30 minutes before adding it to the other ingredients, usually towards the end of cooking. This really draws out the beautiful colour and that royal flavour from it.
According to McGee in On Food And Cooking (p. 423) the liquid should be warm or hot but he doesn't specify a particular temperature; an interesting aside is that he says while the main pigment is water soluble adding some alcohol or fat will disolve additional carotenoids. Here's the quote in full:
Saffron is typically used in small quantities - a few threads, or a "pinch" - and rehydrated in a small amount of warm or hot liquid before being added to a dish, in order to extract both flavor and color. The main pigment is water soluble, but the inclusion of some alcohol or fat in the extraction liquid will dissolve additional fat-soluble carotenoids.
Before doing anything else, I put the saffron in a glass teacup with a tablespoon of water, cover with film, and microwave for a minute.
That's usually ready when I want to put it in with the other ingredients.
I make saffron-orange cookies with cannabutter (citrus perks you up, and saffron is a natural anti-depressant, so I call my "happy cookies". I put the ground (in a tiny pinch of sugar) saffron into the warm (210 F) cannabutter for 30 minutes before I add the butter to the dough mix. The butterfat does the rest.
