What are these bugs on my onions?

February 25, 2009 9:55 PM

How do I deal with these icky bugs on my (store-bought) onions?

For the last few months, I've been noticing that by the time I get to the last onion or two in the bag, the outer layer of the onion--the first layer of flesh beneath the peel--is teeming with very tiny (about 1mm long) white larvae.

Since I can barely see them, I can't tell for certain what they are, but I'm suspecting they're fruit flies. The size is right, and fruit flies are non-burrowing, which would explain why I never find them below the outer layer of the onion. I haven't seen an adult fruit fly in the house since sometime last summer, so I would also assume the onions are coming from the store with the eggs on them. I've tried shopping at different stores, too--it seems to be a universal problem with onions I buy.

Okay, okay, so eating a few cooked bug eggs now and then won't kill me, but it still grosses me out. What I'm doing now is peeling, rinsing, and chopping the entire bag of onions when I buy them, then keeping the chopped onions in baggies in the fridge until I use them. I'd much rather save myself all that extra work at the end of a grocery trip, though, and use the onions one at a time as I need them.

So, my questions would be:
1) Are all the onions I buy actually covered in fruit fly eggs (ugh!), or is this something else entirely?
1a) If yes...at the risk of turning myself off fresh fruits and veggies forever, is all store-bought produce infested?
2) Is there anything else I can do to de-maggot my onions?

posted by tomatofruit to food & drink (6 comments total)

I buy onions a lot and have never seen this. Occasionally when I buy them by the sack, the last couple will mold, but I've never seen bugs. And I've never seen bugs like you describe in any produce I've purchased. Sure, maybe a few tiny bugs in stuff fresh from the farmer's market, and yeah, fruit flies on stuff I've forgotten about for weeks. But not bugs that imply there were eggs present to begin with. So I'm stumped as to why this is happening to you.

I assume you're storing them in a cool, dry place? Storing them alone, not in close proximity with other vegetables (I know that onions plus potatoes can equal quicker rotting)?

It may just be better for you to buy them individually instead of in a bulk sack. And I do think you've hit on a good way to avoid the problem, by prepping them ahead of time. Chopped onions freeze really well, for what it's worth.
posted by padraigin at 10:04 PM on February 25

I've had fruit flies (IIRC) sprouting from my onions - at least (IIRC, again), they were buzzing near the smelly bag, which got Taken Out.

So, yeah: could be them.

If they keep returning, the culprit may be your house's infestation, and not the vegetable. Try going more than a week without any room-temp vegetables. Scour your cabinets in case you've forgotten a potato behind a box of pancake mix, or something like that.
posted by IAmBroom at 10:32 PM on February 25

I would look into how you store them as well; the classic advice given to purchasers of Vidalia onions in bulk (as they are only available for a few months) is to hang them in the garage or pantry in panty hose. I just store mine in the fridge but not everyone has room for that option. (I have a second refrigerator with a rotter crisper that would otherwise go unused.)
posted by TedW at 5:02 AM on February 26

Okay, okay, so eating a few cooked bug eggs now and then won't kill me, but it still grosses me out.

Just another onion data point: this is not what I would consider "normal and expected" where I live.
posted by Civil_Disobedient at 5:11 AM on February 26

nthing that this isn't normal or expected.

If you're having the same problem from different stores, I'd bet that the infestation comes from your house, not the store. Throw out whatever onions (and probably other room-temp fruit/veg) you have, and then wash the area in which you store them with the strongest cleaner you're comfortable using. (Personally, I'd make a dilute bleach solution and wipe everything with that, but if you're more comfortable scrubbing with a cut lemon and baking soda, you can do that, too.) Let everything dry, and then wipe it out again. If you have papered shelves or drawer, you might want to consider replacing the paper, too.

Consider moving any indoor potted plants outside, at least temporarily. Gnats and other gross things will sometimes nest in the soil, especially if the soil is kept too damp.

Take the bag out of your trash can, and then scrub out the inside of the can with, again, the strongest cleaners that you're comfortable using.

Clean out your drains--pour boiling water down them, and then afterwards, take out and clean out the u-bend.

Also, check the rest of your kitchen for infestation. Do you have an old bag of flour pushed to the back of shelf, or maybe a box of cereal that you forgot about? Take everything out, wash it, and discard anything that doesn't look quite right.
posted by MeghanC at 10:56 AM on February 26

A fruit fly trap design (if you're interested) that has always worked wonderfully in my experience is to get a beer bottle-shaped bottle, fill it about an inch high with small chunks of banana and balsamic (or cider) vinegar and a drop or two of dish soap, and leave this for a couple days (uncovered, obvs) in the area where you're having the biggest problem. I know you say that you're not seeing any flies, but if you've got fly babies, some rogue mama's going around crapping them out. You need to find and kill her. This will do that.
posted by phunniemee at 11:10 AM on February 26 [2 favorites]