Brown rice is healthier than white because it's less processed, retaining more of its nutrients. That's a major benefit for the diet, but it poses a handicap for long-term storage. Brown rice has a significantly shorter shelf life than white rice related to its higher nutrient value. The bran that colors the rice is the source of the additional nutrients; the bran's oils spoil over time, ruining the rice. You can eat expired brown rice if the bran oils haven't turned, but even if you do accidentally eat rancid brown rice – unlikely, as the smell should stop you – it won't poison you, though there may be some gastrointestinal discomfort.
When packaged specifically with long-term storage in mind and kept in a stable environment, white rice can easily be stored for 25 to 30 years. Not so with brown rice -- not even close. Under the best storage circumstances, it should be used within two years of buying it. Brown rice as stored by the average consumer in a typical kitchen or pantry has a shelf life of about six months.
Increasing Average Shelf
With some extra care in storing brown rice, it is possible to increase its shelf life. Six months applies to the way people typically keep rice: in a kitchen cabinet or on a pantry shelf. Keeping brown rice in the refrigerator or, for even longer storage, in the freezer can significantly increase the length of time it can be kept. Prior to storing brown rice in a refrigerator or freezer, package it carefully to add protection against sources of moisture such as condensation. With these precautions brown rice can be stored and used for up to two years, well past the expiration date on the package.
Check Stored Rice Carefully
When cooking with stored brown rice, carefully inspect the rice for signs of deterioration or spoiling before cooking. If the bran oil has started to go rancid, the smell will be obvious – dank and musty, with a nose-crinkling sharpness. There are also visible signs of deterioration. The rice grains may look discolored and oily. The grains may even start to stick together in clumps. Depending on the degree of moisture the rice has been exposed to, there may be visible mold. Discard rice when deterioration or spoilage is detected. If the color and texture of the rice look fine and it smells like it should, it can be used without risk, even significantly past the expiration date.
Worth the Trade-Off
The dramatic difference in nutritional value between polished white rice and brown rice is well worth the trade-off in terms of diet and health. Storing nonperishable foods in case of emergency makes a lot of sense, and white rice is best for that. For daily eating, however, a shelf life measured in years isn't as important as the powerful nutritional value brown rice provides. In addition to being a good source of fiber and nutrients, it also offers important plant-based biological compounds including phytoestrogens and phenolic compounds, which have antioxidant and anti-inflammatory properties. Those benefits are worth buying smaller packages of brown rice more frequently.