Spice – How much powder does 1 TBSP of Cumin seeds yield when crushed

I thought this was an interesting question, so I went into the kitchen and had a comparative chew. Anise Seed (or aniseed where I come from) is smaller, darker and gives a more immediate anise hit, but it fades quickly. Fennel seed is two or three times larger and paler. When you chew it, there's little flavour at first, but then a wash of anise flavour comes in. I think fennel tastes a bit softer, smoother, "greener" and more rounded.

If I had to substitute anise for fennel, I'd probably use a third or even a quarter of the original quantity. Although you might just want to leave it out. I agree with bikeboy - the great joy of fennel in Italian food is biting on fennel seed and getting that green-spicy hit in a meat dish (oh! I have a pasta dish with sweet Italian sausage, tomato, cream and fennel that is to die for). I don't think you'd get the same effect with anise.

Converting whole spices to ground spices is not as simple as matching up the weights. Ground spices have a distinctly different flavour from the whole. The freshness of the grind will also affect the taste quite considerably as well as how carefully they have been stored. When the spice is freshly ground it will have a very strong intense flavour, so you would reduce the amount you use slightly. However, ground spices rapidly loose parts of their flavour. The taste changes and you may find you will end up using more than the recipe states in order to get a similar taste. However, you'll never get exactly the same taste, grinding changes the spice.

The best solution is to try to get an supply of the whole spice from an online store. You can then use them whole or grind them yourself, fresh, as the need arises.