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May 27, 2009 04:02 PM

How long can I safely KEEP WARM on rice cooker and crockpot?

Sorry if this was already addressed somewhere. I often keep the cooked rice in the pot on KEEP WARM for a couple of days, same for the crock potted meat.... but I will confess to losing track of how many days sometimes. Is that dangerous? How long is safe and when is it just negligent parenting?!

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  1. You are still alive to post this thread, so whatever you have been doing is fine......No advice is needed...:-)

    2 Replies
    1. re: fourunder

      True enough, but my old, weathered guts might e hardier than my kids'.... and well I couldn't food poison my husband if I tried (assuming I haven't ;) but I try to be a little more responsible for the kids. One of them is under two. I don't know if that makes any difference at all. Maybe it's just a hysterical mom alert.

      1. re: aforkcalledspoon

        All kidding aside, I have left rice uncovered/covered in the rice cooker for 24 hours without incident.......however, my cooker is simply on or off, and shuts off automatically after the rice is done. There is no warm setting. Unless if was above 60 degrees outdoor temerature at any time of the year, I would not give it a thought. Older generations always left out food all day on the table or counter, amazingly even in summer. without serious injury. I would be more concerned and careful if it were a meat or seafood protein left out myself, but not with plain rice......maybe if it were cooked in stock.

    2. If you are using a rice cooker it will dry out your rice alot. Sometimes I just put the entire insert from the rice cooker in the fridge. To reheat it just put a couple of tablespoons of water in it and put it back in the cooker for a cook cycle. Alternately, put the rice in a baggie in the fridge and nuke it for 1-2min. to reheat. I know the scares about plastics so its your call, but when I worked as a cook at a big chain we used to portion the rice in baggies and nuke as ordered.

      You can check for food safety guidelines on what temperature to reheat to in order to make it safe. I think if it goes under 40 degreees it has to be refrigerated. Also the starch content of rice makes it prone to developing bacteria quickly at room temperature. I would just refrigerate and reheat. :)

      3 Replies
      1. re: jamielikestocookandeat

        I guess that was what I was wondering about.... if anyone knows generally what temperature the KEEP WARM function keeps food at. I know it varies with make and model, but just a guideline. Of course you are right about refrigerating food. Unfortunately at the moment we are living with a bar-sized fridge (don't even ask), and so I just leave the food in the pots. The height of laziness!

        1. re: aforkcalledspoon

          Do you have a thermometer? If the temperature is at least 130F, you are fine to hold it at that temp for as long as you want. For instance, in sous vide cooking, folks safely cook a piece of beef at 130F for 72 hours. Of course, FDA says above 140F for holding food, but they also say that over 1.5 hours at 130F is an effective method of pasteurization.

          If you don't have a good thermometer, please get one. But as a rough guideline, if you can't stick a finger in the rice and hold it in there for more than a few seconds, it's hot enough.

          1. re: Joe MacBu

            That is exactly what I needed to know, thank you so much. My children thank you! :)

      2. I've never done this... My rice cooker has the 'warm' setting, but the rice gets crunchy by the time I am ready to clean the cooker after dinner. My crock pot has been on for overnight and a day, but never longer. If you are worried, don't take a risk based on the advice of a message board (not that these people aren't brilliant!) but really...
        (I suppose that includes not taking my advice to not take someone else's advice! Life is such a party, isn't it?!?!)

        1 Reply
        1. re: Boccone Dolce

          really, your rice gets crunchy that quickly? Even after a few days my rice is a little darker, but still moist. Maybe the salesperson wasn't such a con when he was selling me on this brand of rice cooker. Not to say that keeping it in there for days is a good thing! Don't worry, I will disregard your advice to the same degree as everyone else's ;) If it weren't for the damned bar fridge this would not be an issue for me! I would refrigerate my cutlery if I could.

        2. I know you've all been lucky with your rice so far, and I hope your luck continues -- but you can't count on that. The raw rice may contain Bacillus cereus, the spores of which are not killed by boiling, and can produce toxins that cause food poisoning. Cooked rice should be refrigerated after 2 hours, even if it's being kept at a hot temperature. And although it can be refrigerated up to 3 days, it should be reheated only once. Reheating will not kill the spores.

          So-called "Fried Rice Syndrome" results from flash-cooking of chilled, cooked rice that contains B. cereus toxins.

          2 Replies
          1. re: Channa

            While B. cereus spores do survive boiling, they cannot activate at temperatures above 130F. Spores are a dormant state of the bacteria. In order for the toxins to be produced, the spores must first undergo activation, germination and outgrowth under conditions that are favorable for the survival of the vegetative cells (i.e. the metabolically active bacteria). Spores are metabolically inactive since their sole purpose is to survive harsh conditions; spores do not form toxins, only the vegetative cells do.

            However, once the rice reaches hospitable temperatures, the spores will activate and germinate into vegetative cells. Hospitable temperatures for B. cereus growth are between 39F to less than 130F. This is when the toxins get made, some of which are very heat resistant. The main point is that one should minimize how much time the rice spends between 130F and fridge temp. To stay on the safe side, it's a good idea to shoot for at least 140F for a holding temperature. It's actually safer to hold the rice at 140F for several days, than to keep it in the fridge for the same amount of time. The rice at 140F contains only dormant spores; the rice in the fridge potentially contains spores which have germinated and begun to outgrow and produce toxins at a low level. Even after you reheat the rice, the thermostable toxins survive. Of course, in either case, it's all fair game once the spores enter the favorable conditions in your intestines.

            Regardless, I don't understand why anyone would want to keep rice on warm for several days. It wastes energy and gets you worrying about making your kids sick. The whole point of having a rice cooker is to make it super duper easy to cook rice whenever you want it. Why not just cook how much you'll need for the meal and make it fresh each time? The best thing about rice is its freshness and the smell as it cooks.
            As for holding the meat on warm for days, doesn't it turn to mush? Even if it may not be negligent parenting, I think it is negligent cooking.

            Some references:

            From soil to gut: Bacillus cereus and its food poisoning toxins.
            Stenfors Arnesen LP, Fagerlund A, Granum PE.
            FEMS Microbiol Rev. 2008 Jul;32(4):579-606.


            1. re: Joe MacBu

              This is one of the better chowhound posts I've ever seen. I just had two things to add.

              First, when cooking meat for mutiple days you should really employ sous vide for health and safety. Assuming you already have a thermometer, a good large rice cooker and ziploc bags you can start small things but there are now very cheap hand powered vacuum sealers on the market so it's within reach of everyone. In order to control the temperature I have a controller with a built in thermometer, but it can all be controlled manually by adding more hot water. Pulling out all the oxygen lowers the boiling point of water and it means that you can pasteurize meats at a lot lower temperature. At the same time it is dreadfully important that any meat cooked in sous vide must either be served immediately out of the bag or, more ideally, chilled immediately in ice and salt slush and then in a fridge in the ice. Simply putting meat in the fridge in a bag will not chill it quickly enough and you will really risk bacteria. That and it is unecessary to cook for more than 30 hours. The key is constant temperature, not extreme lengths of time. Flank steaks can cook sous vide in only a few hours. After you chill it the juices in the bag will thicken and can be used in a sauce and seperated from fats, which can be used to baste when grilling/frying the meat on the surface (first you heat it in the water bath again).

              Also, rice is very bad to mess with, especially the aforementioned fried rice syndrome. I have learned the hard way that brown rice especially can not be left out for any length of time at all at room temp. I learned the hard way after eating rice that had only been sitting out for one hour or two tops, coming from heat down to room temperature. Within a few hours I felt like a giant bell was ringing in my gut. Hope everyone stays healthy.

              PS if you dont ever want to get food poisoned than stop eating meat and just eat something grown by someone you know.