Q & A Thursday: can you eat leftover rice
Posted by kathryn in Uncategorized
The first question in today’s Q & A Thursday is from Caroline: is it safe to reheat cooked rice?
Raw rice naturally contains a bacteria called Bacillus cereus. In large amounts this bacteria can cause vomiting and diarrhoea.
Bacillus cereus spores survive the cooking process and are not killed off when rice is reheated. So the safety of rice is dependant on how you handle the rice once cooked.
The temperature range of 4°C – 60°C is considered the danger zone for food. These temperatures are the perfect environment for most bacteria, when they are able to grow and multiply at a rapid rate. And the same is true for rice.
The longer rice is within this temperature range therefore, the more likely Bacillus cereus spores are to grow and multiply. And the more chance you have of getting food poisoning from eating it.
Therefore it’s not the reheating of rice which is potentially a problem, but how it’s been stored prior to reheating.
- If you’ve cooked too much rice, put the leftovers in the fridge straight away, so they cool down quickly.
- Keep rice salads in the fridge, right up until they’re needed and serve them cold.
- Be careful of leftover takeaway rice: by the time it’s been cooked, kept warm in a rice cooker, delivered to you, eaten, stored – there’s plenty of opportunity for Bacillus cereus to multiply. I’d throw the leftovers out once you’ve finished the takeaway.
- Keep leftover rice for no longer than one day before re-using.
And remember bacteria are present in many of the foods we eat. And this is natural. Cooking and correct food handling will either kill-off these bacteria, or at the very least prevent the population from over-growth.
For some good information on food safety in the home, take a look at Food Science Australia.
What is Q & A Thursday?
This post is part of Q & A Thursday – a monthly burst of blogging, where you get to dictate the subject matter. Q & A Thursday is all about simple, practical answers to food and diet dilemmas sent in by readers.
If you have a question you’d like answered send me an "email":mailto:me@kathrynelliott.com.au. For more information you can take a look at the Q & A Thursday archives.
03 July, 2008
Comments
Wow, I had no idea about this! It also brings up several questions: what about things like stir-fried rice (which is sometimes kept in the fridge for 3 days or so and eaten again) or rice pudding (ditto)? Does this mean one has to eat any rice dish within 2 days? Yikes.
hmmm….I have been in the habit for years of cooking up enough brown rice to last me all week, keeping it in the fridge and reheating it by dishing it into a strainer and pouring boiling water over it – I would of course chuck it if it smelt too fermented. I, or to my knowledge those I have cooked for, have never had any probs, but your post makes me think this is not a good idea! Would the brown rice last longer than white?
Ricki – to be completely safe you do need to use up the rice quickly. Neither cooking in a pudding or stir frying will get rid of those spores. So you are increasing your chances of getting food poisoning. I’d recommend simply cooking less, so you can use it up quickly.
And the same response to you Lyndal (hi by the way!). Cooking your rice, keeping it in the fridge and then reheating – doesn’t get rid of the spores. And the smell test is not very reliable. Food can be problemmatic, well before it smells bad.
I don’t think there’s any difference between white and brown rice.
Wow – this was an extremely useful tip. Never knew about this. I used to cook rice, same as you Ricki… Thanks for the heads-up, Kathryn!
I cannot agree with the advice that rice should only be kept for a day before being thrown out.
Since I read :
http://www.timesonline.co.uk/tol/life_and_style/food_and_drink/article5205697.ece
I feel much better about keeping rice for more than 1 day (if I’ve cooked it/stored it)
Amanda
Amanda – there seems to be a fair bit of debate about this. The latest advice I’ve seen here in Australia is rice can be stored for up to three days. I still think seven days is too long.
But, you’re right, it is about how you cook and store it.
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