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I left the rice overnight in the fridge and it smells fine, and a sample tasted fine but the color looks unappetizing. Is it safe to eat?

In response to the comments, it was warm and white when I put it in the fridge. Here is a photo that appears less colored than it was. At the bottom underneath it was all purple and blue: enter image description here

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    Was it still warm when you put it in there? Dec 2, 2017 at 4:34
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    Rice? Rice is so cheap that I'd just throw it out. A interesting question is why it would turn blue/purple.
    – MaxW
    Dec 2, 2017 at 4:48
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    If you are still wondering if it is edible, it sounds like you still have it. Could we see a photo??? pretty please?
    – Lorel C.
    Dec 2, 2017 at 5:10
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    If it was really in a fridge overnight, with only a little cooling time before that, I'd be very surprised if it was mould. Is it a coating of colour, or does the colour go right through? Is there anything at all mixed with it or in the same container?
    – Chris H
    Dec 2, 2017 at 18:20
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    Stephie has a good question: in addition to the lentils, are there black beans, or any other so called "black" foods, in that dish along with the rice? Black beans would stain the rice and make it look kind of purple, sort of like in your picture.
    – Lorel C.
    Feb 14, 2018 at 18:07

1 Answer 1

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From a bit of research, there is a bacteria called Chromobacterium suttsuga that is put on some types of rice to provide pest-control:

The bacterium’s toxins can be combined with chemical compounds and then applied to soil, plants or seeds. To control soil-dwelling pests, rice grains can be treated with the toxins and applied to the soil, where pests will feed on the treated grains.

This source seems to be referenced in a lot of other scientific papers for agriculture for talking about Chromobacterium suttsuga and pest-control. Some people claim seeing the discoloration on rice after a few days of being left in the fridge in a dark humid environment (like the bottom of a storage container where the discoloration appeared). There are a few forums about this you can find by Googling "white rice turns purple".

For the question on whether or not it is safe to eat, since we don't have the tools to do any biological analysis to be certain it is Chromobacterium suttsuga in the rice I would recommend against eating it. Even though the papers claim this strain of bacteria is safe to consume.

Source: https://aggie-horticulture.tamu.edu/extension/newsletters/vpmnews/mar04/mar04newdefense.html

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  • How does this strain of bacteria form? Mar 20, 2019 at 5:13
  • Any bacteria on the raw rice would likely be killed by the cooking process. I suspect the discoloration in this case is caused by a different bacteria. But, even if it's the same one, it also indicates that conditions were favorable for other types of bacteria to grow, too.
    – mrog
    Jan 22, 2020 at 21:00

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