Rice is not especially difficult to cook, but it's much more forgiving in large batches than small ones. If meals in your household are modest in size, it's often more convenient to prepare a large batch of rice, and then freeze and portion it for later use. Rice must be thawed correctly to avoid potential illness -- Bacillus cereus, a grain-loving pathogen, can populate it surprisingly quickly -- but three methods are both safe and widely used.
Remove your rice from the freezer, and transfer it to the refrigerator. If you're thawing more than one package, distribute them evenly on the shelf rather than stacking them. This permits faster, more even thawing.
Check small portions after 12 hours or the next morning. If there are a few large clumps of still-frozen rice, you can speed thawing by breaking them up with your fingers. At this stage, the rice can be reheated by your favorite method and eaten. Large portions will usually not be completely thawed, but you can accelerate the process by breaking them into smaller pieces and separating them pieces into bags or containers.
Test larger portions of rice again in another eight to 12 hours. It's ready to use if it's thawed or if there are only a few small frozen spots. Reheat the thawed rice to a temperature of 165 degrees Fahrenheit to ensure food safety, or label it with the thawing date and use it within three to four days.
The Water Method
Remove your rice portion or portions from the freezer. If you're uncertain whether the packaging is waterproof, place each portion in an individual zipper-seal bag as a secondary defense against unwanted leakage.
Place a large pot or mixing bowl in your sink, and arrange the rice portions loosely in the bowl. Fill it with cold water, and then turn the tap until water is entering the bowl at a bare trickle.
Check the rice every 20 to 30 minutes, rearranging the packages each time if you're thawing multiple portions. A single portion of fluffy, long-grain rice can thaw in as little as a half-hour, but larger portions and denser, moister rice can take longer.
Remove the rice from its water bath when it is fully or near-fully thawed. Dry the packaging and reheat the rice immediately, or store it in the refrigerator temporarily while you prepare the rest of your meal. Rice thawed by the water method should always be used on the same day to minimize the risk of foodborne illness.
Remove your rice portion or portions from the freezer. If it has been stored in a microwaveable container, open the lid or any built-in vent it might have. Bagged portions should be unwrapped and transferred to a microwaveable dish with a lid or a bowl covered loosely with plastic cling wrap.
Set your microwave to its "Defrost" or "Thaw" setting, or -- if you've found these setting to work erratically on your microwave -- to the 50 percent power setting.
Microwave the rice at this reduced power setting for 2 to 4 minutes in the case of small portions or up to 10 minutes for large portions. Open the door and check your rice at 2-minute intervals, stirring it occasionally and breaking up large frozen clumps to ensure even warming.
Remove the rice from the microwave when it is nearly thawed, but retains a few small frozen sections. Let it rest, covered, for 10 minutes. This provides opportunity for the temperature to equalize throughout the rice, ensuring even cooking.
The refrigerator method is the safest for any frozen food and should be your default choice whenever time permits. The long thawing time minimizes textural damage to the rice, and because it remains at a food-safe temperature from start to finish, the risk of foodborne illness is minimal. If you wish to thaw enough rice for multiple meals, this is the method you should use.
If you live in an area where water usage is tightly regulated, or if you simply find the sound of trickling water irritating, drain and refill the bowl every 20 to 30 minutes instead of having the tap run continuously. The result is similar.
The water-thawing method raises your rice's temperature above the 40 F threshold for food safety, so it should be reheated or cooked into a new dish on the same day. Microwave thawing is uneven and creates pockets where the rice rose well into the food-safety "danger zone," creating the potential for rapid microbial growth. Rice defrosted in the microwave should be cooked or reheated immediately.
Freezing your rice in small, flat portions is the most practical option if you plan to do it regularly. They'll freeze and thaw more quickly, which makes the frozen rice more convenient to use. The USA Rice Federation recommends using frozen rice within six months to ensure the best quality.
As with any leftovers, thawed rice must be reheated to a temperature of 165 F to ensure food safety. Use an instant-read thermometer, if you have one, to verify that you've done that successfully. If you reheat the rice in a microwave oven, stir it and test with the thermometer in several places to ensure that the whole portion has reached a food-safe temperature.