But the ones that I cook most with are lemons. They can be quite costly in Singapore some times and it's not like I cook with them every single day to warrant me buying them fresh every week. So I buy them when they are cheap and freeze them.
Obviously, one doesn't freeze the lemon just like that, unless you cook the entire lemon whole in your dish. So I separate out the zest and the juice. First I wash the lemons clean and dry them well and then proceed to zest them. I have a confession to make - I don't own a microplane nor do I own a zester. I use a fruit peeler and take off the zest in huge chunky pieces and freeze them. If my recipe calls for thin zest, I just chop the zest up finely. It has worked well for me all this time but I'm sure purists would be up in arms seeing how I actually have a fairly significant amount of pith on the zest. Again, the untrained palate of my husbands can't detect the difference so I blissfully continue what I'm doing until such a time where I can get my hands on a zester.
The zest goes straight into small ziplock bags (which I reuse) - 1 lemon, 1 bag. The juice is frozen into ice cubes and I bag them into ziplock bags too. 1 ice cube of juice is about 2 tablespoonfuls of juice. I label the bags with dates on sticky labels and know that I'll always have lemon at hand!