What you see: Green wormy grubs in broccoli, maybe even left behind in your cooking water (where they probably turned white). They may have also eaten away at part of the broccoli.
What it is: Caterpillars, specifically imported cabbageworms
Eat or toss: Pick off the caterpillars and cut away any areas that have been chewed on. For extra comfort cook the broccoli rather than eat it raw.
You’re happily blanching your broccoli for dinner. Just as you go to strain it, you notice, in horror, that the ghostly white corpses of a number of caterpillars have floated to the top of the pot. You had picked out SOME green little caterpillars before cooking the broccoli, but apparently there were many more and you've just boiled them into oblivion. It’s 8 p.m. You don’t have time to make anything else. But there, next to the broccoli you so eagerly bought at the farmers market, are the caterpillars. Ewwwwww.
Ok, fine. This happened to me. And I, uh, ate the broccoli. And I survived.
For extra comfort, I spoke with Rutgers microbiologist Don Schaffner and University of Kentucky entomologist Ric Bessin. While none of us found the situation terribly appetizing, Schaffner said the caterpillar was unlikely to be carrying any pathogens that could survive boiling and then sicken someone. Bessin said even accidentally eating one of the caterpillars probably wouldn’t be a disaster—they are a very common species called "imported cabbageworms" and don’t contain any toxins known to harm people (but some caterpillars do, so be careful out there).
In this scenario, you want to be most careful with the parts of the broccoli that the caterpillars have obviously munched on. Areas where they've cut into the broccoli will be more vulnerable to microbes and rot. The odds of a human pathogen taking up residence are low, but not impossible. In any event, the chewed on areas in the image above are clearly starting to rot (they're soft, slimy and discolored) and will not taste good. I trimmed them off.
A common pest
These caterpillars, which eventually become little white butterflies, are common and frustrating pests. They love hanging out in the jungle of florets in the broccoli head, making them especially hard to find and remove.
If you often discover caterpillars in your broccoli, you might try soaking it in salt water. A couple corners of the internet (here and here) endorse this technique. While he hadn't tried it, Bessin said the method could work because the caterpillars would float in salt water.
So, if you find yourself with a head of broccoli that’s also serving as a hang for a bunch of caterpillars, or you discover the caterpillars AFTER cooking, none of your options are terribly appealing, but just keep in mind that, with proper handling, the broccoli is still fine to eat.
Ric Bessin. Extension entomologist. University of Kentucky.
Don Schaffner. Microbiologist. Extension Specialist in Food Science and Distinguished Professor at Rutgers University.
Cabbage Insects. Ric Bessin. Extension entomologist. University of Kentucky College of Agriculture.
C'mon over! We're having a worm boil!