# How do fruit flies find my bananas? **URL:** \ **Category:** Factual Questions\ **Created:** [April 16, 2008, 2:05am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541 "2008-04-16T02:05:54Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![DaveRaver](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/daveraver/32/1078_2.png) [@DaveRaver](https://boards.straightdope.com/u/DaveRaver)\ **Post date:** [April 16, 2008, 2:05am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/1 "2008-04-16T02:05:54Z")
Do fruit flies actually smell my bananas from outside my house and come inside, or are there tiny fruit fly eggs on my bananas that hatch and create fruit flies? I never see fruit flies unless I have bananas! What is the straight dope? ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [April 16, 2008, 3:16am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/2 "2008-04-16T03:16:58Z")
Fruit flies may like a banana, but time flies like an arrow. ---
**Author:** ![Stan\_Doubt](https://avatars.discourse-cdn.com/v4/letter/s/53a042/32.png) [@Stan\_Doubt](https://boards.straightdope.com/u/Stan_Doubt)\ **Post date:** [April 16, 2008, 3:51am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/3 "2008-04-16T03:51:29Z")
From [here](http://www.mass.gov/dep/recycle/reduce/flies.htm), a Mass DEP site about indoor composting. > [@](#): > > occasionally fruit flies seem to appear in our kitchens as if by spontaneous generation…This is because they can travel into our homes, unbeknownst to us, as larvae on the fruit we buy. The adults lay their eggs, invisible to the naked eye, on bananas and other fruits, which later hatch while the fruit is in our fruit bowls…Since banana peels seem to be the most common bearer of fruit fly larvae, some people prefer to compost banana peels in outdoor bins only. ---
**Author:** ![GilaB](https://avatars.discourse-cdn.com/v4/letter/g/8e7dd6/32.png) [@GilaB](https://boards.straightdope.com/u/GilaB)\ **Post date:** [April 16, 2008, 4:38am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/4 "2008-04-16T04:38:35Z")
An [SDSAB report](http://www.straightdope.com/mailbag/mfruitfly.html) on the phenomenon, which basically agrees with the Mass DEP. ---
**Author:** ![Chimera](https://avatars.discourse-cdn.com/v4/letter/c/8e8cbc/32.png) [@Chimera](https://boards.straightdope.com/u/Chimera)\ **Post date:** [April 16, 2008, 4:41am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/5 "2008-04-16T04:41:16Z")
I’m sorry, I thought you’d enjoy them. Nope, as posted, it’s the old Invisible Egg Trick. Back in about November, I had a sudden, serious infestation of the little buggers. They were just everywhere. Then one day I looked up at the old liquor bottles on top of my bookshelf. There must’ve been something like 40 of the little bastards crawling around the top of a very old bottle of Rumplemintz that apparently had a lot of dried residue around the cap. :eek: I kid you not. ---
**Author:** ![Crocodiles\_And\_Boulevards](https://avatars.discourse-cdn.com/v4/letter/c/ee7513/32.png) [@Crocodiles\_And\_Boulevards](https://boards.straightdope.com/u/Crocodiles_And_Boulevards)\ **Post date:** [April 16, 2008, 4:47am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/6 "2008-04-16T04:47:52Z")
I accidentally came up with a home remedy for fruit flies (what we always called trash gnats) in college. My friends had a very, very sloppy apartment, and these bugs were flying around all over the place. One day, I came over and brought a jar of kosher dill pickles with me to eat with my sandwich. After I finished, I forgot to put the lid back on immediately and went about doing whatever. I come back 5 or 10 minutes later, and, I swear, there must have been 20 or more of those little gnats floating dead in the pickle brine. More of them were swirling around the top of the jar and crawling around on the glass. While I was a little disgusted, I also saw how this could be a cure to their infestation. After a while, all the fruit flies disappeared into the bright green brine. It was nice! ---
**Author:** ![bouv](https://avatars.discourse-cdn.com/v4/letter/b/bc8723/32.png) [@bouv](https://boards.straightdope.com/u/bouv)\ **Post date:** [April 16, 2008, 4:57am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/7 "2008-04-16T04:57:25Z")
[QUOTE=Chimera] Back in about November, I had a sudden, serious infestation of the little buggers. They were just everywhere. Then one day I looked up at the old liquor bottles on top of my bookshelf. There must’ve been something like 40 of the little bastards crawling around the top of a very old bottle of Rumplemintz that apparently had a lot of dried residue around the cap. :eek: I kid you not. [/QUOTE] Oh yeah, fruit flies LOVE any sugary liquor. I remember watching some random show on TLC or Discovery a number of years ago about a health inspector going to places. He goes to one restaurant, and at the bar, picks up a random bottle, swirls it around, and shines a flashlight into the bottom. HUNDREDS of little specs where twirling around in the bottle…each spec was a dead fruit fly because the place used their liquor so infrequently. Odds are every bar/restaurant has at least a few bottles of liquor that are used very infrequently and have dead bugs in them. ---
**Author:** ![antechinus](https://avatars.discourse-cdn.com/v4/letter/a/fbc32d/32.png) [@antechinus](https://boards.straightdope.com/u/antechinus)\ **Post date:** [April 16, 2008, 8:38am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/8 "2008-04-16T08:38:45Z")
Fruit fly are attracted to the chemicals released when the fruit starts to ripen and decompose. Mould activity is great for attracting them. When chemicals such as ethyl acetate, ethanol and acetic acid are given off by the fruit, a passing fruit fly gets a whiff and hones in on the source. Of course it could be a false alarm, like a vinegar bottle or pickles, but chances are it is food. ---
**Author:** ![stuyguy](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@stuyguy](https://boards.straightdope.com/u/stuyguy)\ **Post date:** [April 16, 2008, 1:14pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/9 "2008-04-16T13:14:43Z")
Every six months to a year we have a fruit fly question. Hell, I even started one myself, a couple of years back. We always get a thousand and one home remedies to \*stop \* a ff infestation, but we never hear how to _prevent_ one in the first place. So, what I want to know is, can anything be done to rid a new bunch of bananas of any unhatched eggs it may be carrying? Are the eggs on the outside of the peels, or are they buried down below the surface? Do they wash off easily? If not, can they be scrubbed off? Do the eggs get laid on one particular spot, like the tips, or can they be anywhere on the fruit? Can I douse the bananas in some sort of harmless homemade solution that will kill the eggs before they hatch? ---
**Author:** ![flex727](https://avatars.discourse-cdn.com/v4/letter/f/258eb7/32.png) [@flex727](https://boards.straightdope.com/u/flex727)\ **Post date:** [April 16, 2008, 1:44pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/10 "2008-04-16T13:44:21Z")
[QUOTE=stuyguy] Every six months to a year we have a fruit fly question. Hell, I even started one myself, a couple of years back. We always get a thousand and one home remedies to \*stop \* a ff infestation, but we never hear how to _prevent_ one in the first place. So, what I want to know is, can anything be done to rid a new bunch of bananas of any unhatched eggs it may be carrying? Are the eggs on the outside of the peels, or are they buried down below the surface? Do they wash off easily? If not, can they be scrubbed off? Do the eggs get laid on one particular spot, like the tips, or can they be anywhere on the fruit? Can I douse the bananas in some sort of harmless homemade solution that will kill the eggs before they hatch? [/QUOTE] Now THIS is the kind of post worthy of the Straight Dope! ---
**Author:** ![stuyguy](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@stuyguy](https://boards.straightdope.com/u/stuyguy)\ **Post date:** [April 16, 2008, 4:26pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/11 "2008-04-16T16:26:53Z")
[QUOTE=flex727] Now THIS is the kind of post worthy of the Straight Dope! [/QUOTE] :: _Hours pass with no replies_ :: Apparently not! ---
**Author:** ![Bearflag70](https://avatars.discourse-cdn.com/v4/letter/b/8e7dd6/32.png) [@Bearflag70](https://boards.straightdope.com/u/Bearflag70)\ **Post date:** [April 16, 2008, 4:30pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/12 "2008-04-16T16:30:24Z")
Soak them in bleach? ---
**Author:** ![ratatoskK](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ratatoskk/32/2987_2.png) [@ratatoskK](https://boards.straightdope.com/u/ratatoskK)\ **Post date:** [April 16, 2008, 4:39pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/13 "2008-04-16T16:39:04Z")
Wash them in pickle juice! ---
**Author:** ![flex727](https://avatars.discourse-cdn.com/v4/letter/f/258eb7/32.png) [@flex727](https://boards.straightdope.com/u/flex727)\ **Post date:** [April 16, 2008, 5:18pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/14 "2008-04-16T17:18:23Z")
[QUOTE=stuyguy] :: _Hours pass with no replies_ :: Apparently not! [/QUOTE] Au contraire, let the other boards handle the easy questions. More difficult questions can take time, even on the SDMB. ---
**Author:** ![Spectre\_of\_Pithecanthropus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spectre_of_pithecanthropus/32/12343_2.png) [@Spectre\_of\_Pithecanthropus](https://boards.straightdope.com/u/Spectre_of_Pithecanthropus)\ **Post date:** [April 16, 2008, 7:14pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/15 "2008-04-16T19:14:57Z")
Very tasty, thanks for asking. ---
**Author:** ![Carol\_the\_Impaler](https://avatars.discourse-cdn.com/v4/letter/c/6a8cbe/32.png) [@Carol\_the\_Impaler](https://boards.straightdope.com/u/Carol_the_Impaler)\ **Post date:** [April 16, 2008, 9:34pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/16 "2008-04-16T21:34:33Z")
Ba-dum-CHING. ---
**Author:** ![pravnik](https://avatars.discourse-cdn.com/v4/letter/p/8edcca/32.png) [@pravnik](https://boards.straightdope.com/u/pravnik)\ **Post date:** [April 16, 2008, 9:59pm UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/17 "2008-04-16T21:59:25Z")
[QUOTE=Spectre of Pithecanthropus] Very tasty, thanks for asking. [/QUOTE] Dangit. ---
**Author:** ![Darryl\_Lict](https://avatars.discourse-cdn.com/v4/letter/d/7cd45c/32.png) [@Darryl\_Lict](https://boards.straightdope.com/u/Darryl_Lict)\ **Post date:** [April 17, 2008, 5:53am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/18 "2008-04-17T05:53:08Z")
[QUOTE=stuyguy] So, what I want to know is, can anything be done to rid a new bunch of bananas of any unhatched eggs it may be carrying? Are the eggs on the outside of the peels, or are they buried down below the surface? Do they wash off easily? If not, can they be scrubbed off? Do the eggs get laid on one particular spot, like the tips, or can they be anywhere on the fruit? Can I douse the bananas in some sort of harmless homemade solution that will kill the eggs before they hatch? [/QUOTE] You need a food [irradiator](http://en.wikipedia.org/wiki/Food_irradiation). I’d go get a really thick lead box and toss some Cobalt-60 into it. Warning: This technique may be hazardous to the consumer, as you need a decent amount of shielding to sufficently attenuate the gamma rays. And by the way, I’m kidding, so don’t attempt this at home. 🙂 ---
**Author:** ![Amblydoper](https://avatars.discourse-cdn.com/v4/letter/a/fbc32d/32.png) [@Amblydoper](https://boards.straightdope.com/u/Amblydoper)\ **Post date:** [April 17, 2008, 6:13am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/19 "2008-04-17T06:13:35Z")
I fought with the fruit flies for months when I moved into my apartment. I almost bug bombed the little buggers, but a search here on the dope advised not to (they would just leave, and come back when the poison was gone. Things got so bad at one point, that I would be eating, say, ice cream, and if I left it unattended for more then 15 seconds, at least one fly would have landed on it. One day, I accidently left a half once of orange juicein a glass, and I came home later to find a swarm around the glass. This gave me an idea. Each day, I poured a tiny amount of juice in a glass before leaving for work. When I came home, I would attack the swarm with bug spray. I must have killed thousands of flies in the worst month of the infestation. I also spent alot of time swatting at them in the kitchen. if there was no food to gather near, they would find a wall in the kitchen to sleep on. Eventually, they just disappeared. I don’t know where they came from, or where they went. I am hoping they wont return this year. I am not a tidy person, but I am not filthy. I am convinced that the flies were not here because of my habits. might have to start saving pickle juice. ---
**Author:** ![Ca3799](https://avatars.discourse-cdn.com/v4/letter/c/9f8e36/32.png) [@Ca3799](https://boards.straightdope.com/u/Ca3799)\ **Post date:** [April 17, 2008, 11:29am UTC](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541/20 "2008-04-17T11:29:49Z")
My only so-so helpful advice: I bought a cantaloupe and a pineapple the other day from a store where I saw a few fruit flies buzzing around. I brought the items home and washed them right away. The next day I had 2-3 fruit flies, anyway. I cut up the fruit and refigerated it, and put the rinds in the trash. Later, when the flies went to the trash to get ot the rinds, I quickly closed up the trash and took it out. This worked pretty well. [Next page](https://boards.straightdope.com/t/how-do-fruit-flies-find-my-bananas/445541.md?page=2)