I can tell the difference between the different varieties of rice, but i do find difficulty in telling difference between the taste of different brands of rice.
Since the cooking of rice has been raised in this thread, i would like to comment on a few things;
1.a. Now days you do not have to wash rice, people did this in the olden days when it was often quite dirty/dusty, but now days almost all rice sold in shops is pre-cleaned and so there is no need to wash it yourself after buying it- i've also heard that washing pre-washed rice can also make it loose some of its nutrients.
1.b. I used to have difficulty cooking rice in the past, but i would say i am pretty good at cooking it now i have honed my methods to better perfection.
My way of cooking rice;
a. Measure out 100ml's of rice- 100ml's/1 cup of rice equals one decent sized portion roughly.
b. Get your saucepan- the more surface area it has on the bottom the better. Put a tiny amount of oil (i personally use olive oil) in the bottom of the pan- this will help prevent the rice sticking to the bottom of the pan and also help flavor it. If you want, you can also add a small handful of finely chopped white onion.
c. Heat the pan up to a medium to high heat- if you've added chopped onion, fry it in the small amount of oil in the pan until it starts to soften, then add the rice and stir the rice in the pan to help coat it in oil. If you are not using onion, then as soon as the pan is hot enough, just stir the rice in the oil to coat it in the oil.
d. Once you've done this add cold water to the rice- the amount of water you use depends on the amount of rice you are cooking, generally speaking, you should use twice as much water as you use rice (so 100mls of rice needs 200mls of water).
e. As soon as you've added the water, turn the heat on the hob down to the lowest setting and put the lid on the pan.
f. After you've done this, just leave the rice alone to let it cook.
Try and refrain from stirring the rice like you would with pasta- the steam/heat which builds up in the saucepan once the lid on it has been put on and the temp has been turned down on the hob is crucial to cooking the rice well (and preventing it from drying out), so if you take the lid off you will loose a lot of this important steam.
Also, rice releases starch easily when it is stirred, and if you stir it while cooking it will release a lot of starch which will make the rice stick together in a bad and un-tasty way.
As long as you use the right amount of water and cook the rice on the right heat (and use a little oil too), it should not stick to the bottom of the pan even when the rice has absorbed almost all of the water.
g. How long the rice takes to cook depends on the variety. Basimati (sp?) rice can take as little as 15mins to cook, while short grain rices can take as long as 30mins to cook.
h. When the rice looks cooked enough, remove the pan from the heat and fluff up the rice with a spoon (preferably wooden) and leave it to steam/cool off in the pan a bit with the lid taken off the pan for about 10mins. Then serve

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i. I found a lot of difficulty finding Japanese varieties of rice where i live, however i have found that risotto rice makes a good substitute for short grain Japanese white sticky rice.
If you want to make sushi, its vital you use a sticky rice (short grain white risotto rice can be used if you can't find any Japanese rice) and you will need to add a special warm rice wine vinegar solution (i think it has salt and sugar in it, i have a recipe for it somewhere) to the rice after its cooked to help give it a glossy look and authentic flavor.