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Jun 19, 2012 04:21 PM

Room Temp Sushi Rice Storage- Non Alarmist Advice Sought re:Food Safety [moved from Home Cooking]

I often purchase prepared white sushi rice at my local Whole Foods.I used to store it in the frig, but lately I have been keeping it on the counter in its original closed plastic container. I use it up in 3-6 days, usually in maki. I did once see it go visually moldy after 1+ weeks. Per normal, the sushi rice consists of cooked white rice that has been tossed w/ rice vinegar and a little sugar. With specific regard to this product, I am wondering what significant health hazards I may not be aware of. I am far from an alarmist in this but am curious. The vinegar and sugar seem to have a preservative effect on the stability of the rice when held at room temp. Thanks much.

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  1. Someone once gave me a long diatribe about how all Asian restaurant food poisoning cases came from improperly stored cooked rice, and about how often they are supposed to throw it away and start again.

    That said, the vinegar and sugar probably do provide some preservative effect.

    I probably wouldn't risk it, myself, having had food poisoning too many times!

    Curious, why don't you just put it in the fridge?

    8 Replies
    1. re: sandylc

      cuz it gets hard and you have to nuke it and wait for it to cool. i know i know- big deal!

      1. re: opinionatedchef

        This is the first time I've ever heard of buying pre-cooked sushi rice, but then I rarely shop at whole foods, but none is available on However, I DO make it from scratch every time I make sushi. So I'm curious if you use it for anything but sushi, as well as why you don't make it fresh?

        In regards to your question, I would not store ANY cooked rice anywhere except in the refrigerator. Too risky. You only die once (usually), and there are kinder ways to go than from ANY form of food poisoning! '-)

        1. re: Caroline1

          caroline, why i don't make it? it's called lazy! and i use sushi rice only for sushi ,including inari.

          1. re: opinionatedchef

            Thanks! You've breathed new life into this curious old cat.

            I tried "supermarket sushi" from a store similar to Whole Foods in my area (Central Market) and it made me so very grateful I make sushi myself. The rice was abominable, and I like my nori freshly toasted and still a bit crispy by the time I chew it. I've never had that quality of sushi in this area, but then I I;ve never had sushi from Whole Foods either. Do they make sushi for you while you wait, or is it ready made in little black trays?

            1. re: Caroline1

              they have both-ready to go and made to order. no Japanese people IME. i only buy the ready made rice (you have to ask, and make sure they don't squish it down).Very occasionally i have had to add a little rice vinegar. They also have a multligrain rice which is my fav.

              1. re: opinionatedchef

                Call me wierd, but if I don't fan and polish the rice myself, I don't feel like I'm eating sushi. Big Tuna told me I make sushi "like a grandmother." LOL

                1. re: Caroline1

                  "...but if I don't fan and polish the rice myself, I don't feel like I'm eating sushi."
                  I take it then that if (and when) you were to ever eat sushi in a Japanese restaurant, whether it be at the place down the street from you or at Sukiyabashi Jiro, you "don't feel like you're eating sushi"?

                  1. re: huiray

                    LOL! If I ever find an affordable sushi bar that makes excellent sushi, I will leave it up to the chef whether or not he fans his rice to polish it, as long as his end product is excellent. When I make sushi at home, I fan. I think it makes a difference. As I understand things, most contemporary sushi chefs don't bother.

    2. When I was getting my degree in Food Science, many moons ago, they showed us a poster that said "please don't eat the mold". The people with Pretty Heavy Diplomas had discovered "aflatoxins" in peanuts and other things which had some pretty scary health consequences.

      That stuck in my head: it still makes me squirm to cut the spots off cheese and continue eating it..........but I do. ;-) Just about anything else that goes moldy gets thrown out. Your rice is probably fine, but i'd refrigerate it.

      1 Reply
      1. re: applgrl

        At cheese stores, the tshirts say, "the mold is supposed to be there".

      2. rice in general has some sort of bacteria that releases a toxin. when you reheat the rice, you can kill the bacteria, but not the toxin. I may not be explaining it right, but the short answer is that rice is fairly dangerous and is usually the cause of getting sick from a buffet or something. I don't know if the seasoning for sushi rice makes a difference, but my thought is that vinegar might help but sugar may hurt. Anyway, I would definitely keep cooked rice in the refrigerator. or even freeze it.

        4 Replies
        1. re: cocktailhour

          I don't think I have ever got sick from cooked rice left out at room temperature for a few days. The appearance (e.g., is there this certain sticky threads, or change in texture in spots, etc) and smell, if any, has served me sufficiently well over 30-40 years.

          1. re: huiray

            this actual experience is exactly what i appreciate hearing about. thx.

          2. re: cocktailhour

            There is a southeast asian dish, like a dessert, that is fermented sticky rice. In jars, or plastic cups, yum.

            1. re: cocktailhour

              I see sugar as a preservative. It is acidic, for one thing. The best way to keep raw fruits such as strawberries. Not a liability, an asset. Lemonade goes fizzy? a step closer to beer.

            2. A very serious food safety threat is bacillus cereus. Do NOT leave cooked rice out at room temp for more than 4 hours, ever! This is a killer.

              1. FWIW, every staff member of every Japanese restaurant I have ever been in, including myself, have been eating rice that has sat out overnight. Every day. We all take it home and let it sit on the counter and still eat it up to three days after it's made. As far as I know, none of us has ever gotten sick from doing so. I'm not saying it's safe, but I thought I should share my experience. One curious thing I've noticed is that different brands of rice and/or different rice cookers seem to affect the shelf life greatly. I cook some rice at home and the next day it's slimy and gross. I have never been able to figure out why. Sushi rice that has sat out always tasted pretty bad to me, so I don't eat it the next day, but I have heard of restaurants that reheat it and serve it the next day. Of course those are horrible restaurants, but as far as I know they haven't killed anyone. The problem with sushi rice is that it's mixed up after it's cooked. So if it gets contaminated by something the bacteria would grow throughout the rice, whereas if you boil rice in a pot and leave it there any bacteria would have a harder time getting past the surface. Also, my new rice Japanese cooker came with instructions to reheat rice that's left in it. Like I said, I'm not saying it's safe, but I'm probably going to do it for the rest of my life just like everyone else I know unless something happens to me personally to change my mind. I'm sure someone is going to tell me about my imminent demise, but I'm OK for now, and I'll repost if I get sick. So far twenty years of doing the same thing and no problems.

                3 Replies
                1. re: la2tokyo

                  Yes, my Asian friends leave their rice out. I will too, depending on the season. As with my bread, I find rice will mold more quickly in summertime. So I refrigerate it then.

                  1. re: la2tokyo

                    I can not say the same for the Japanese restaurant we own. We refrigerate everything after our day is over. Rice definitely goes into the refrigerator when our door is closed.

                    1. re: vttp926

                      Taking it home was what the poster described.