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Problem

I've purchased some broccoli, and it is pockmarked by short, black streaks:

enter image description here

I've been informed by my father that it indicates rot, although the broccoli otherwise appears firm.

A comment on Reddit appears to offer a more reliable explanation:

Those black "spots" are evidence of Xanthomonas campestris, a bacterium/pathovar, a disease common to cruciferous vegetables and some turf grasses - it's also known as "black rot".

I know about it because of that bacterium's use in the production of xanthan gum, which gives me the shits in a major way. Sorry for the TMI bit.

If I see black rot, I don't buy it. The optimal temperature of this bacterium ranges from 77-85°F (I like to eat, and I minored in Environmental Engineering). IMHO if I see evidence of this, the plants have been stored in a too-warm environment and it's a pass for me. Read up on this, if you wish.

However:

  1. It doesn't explain well whether that bacteria renders the food unsafe to consume; and
  2. It is in response to a photograph which differs in that the black spots are inside the vegetable, but not visible outside.

I am predisposed to trust sealed produce from a supermarket purchased in the UK to be safe, but exceptions always exist.

(Lack of) Duplicates

Relevant searches solely return Likely cause and virulence of black spots inside outwardly unmarked broccoli, which isn't similar.

1 Answers1

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I don't think it is possible to say for sure that this is Xanthomonas campestris (or black rot). It could just as easily be a variation in the coloring or maybe even oxidation or bruising. Black rot is generally diagnosed by looking at the leaves. You can see pictures at the linked site. If you think you can confirm black rot, it is probably not a good idea to eat it, though this site says that vegetables with low levels of black rot could be salvageable.

Have you tried peeling a layer of the stem? Does the discoloration continue past the surface? If if were me, and I could peel away the discoloration, I would probably eat it, but don't overthink this. You are concerned. Life is too short. Broccoli is fairly cheap. Compost it and get some fresh broccoli.

moscafj
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