The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

What kind of insect is this in my wheat grinder - left dormant for 8 years ?

UncleCharlie's picture

What kind of insect is this in my wheat grinder - left dormant for 8 years ?

I got out my 30 year old Magic Mill wood stone wheat grinder, after not being used for at least 8 years.  It was stored in the laundry room, and I had stupidly left about a half teaspoon of hard red winter wheat flour in the collector (& stone grinding area).  I was surprised to find about 8-10 of these dark brown/black appearing larvae still alive and moving around after all this time.  They are about 1/2" long, and I took these photos with a digital microscope, so they look larger than life.

Larvae image #1

Larvae Image #2


I have not seen any of the more typical brown flour beetles that chomp through boxes and bags (about the size of a small sesame seed), nor any moths.  There was also tons of carmel colored smaller, dried out poppy seed size particles & some webs all over every aspect of the grinder.  I scraped some and took another shot that is more detailed under microscope.  I'm assuming these must be dried out eggs?

Larvae Eggs ???

Anyway, I'm totally freaked out about using this old Mill, as it is very hard to get it all apart enough to clean thoroughly...and am thinking about just getting a new Nutramill to replace it.


Any idea what these critters are...and how they could still be alive after at least 8 years?


I wasn't sure where to post this, but I had linked photos, so if moderator needs to move it, please do.

ericb's picture

Never thought I was squeamish until I saw those pictures. I think I just threw up a bit in the back of my throat.

You could probably use a stiff-bristled brush to loosen up anything disgusting, then run through a few batches of wheat berries to help clear things out. I'm no expert, but I think that as long as you use the flour soon after grinding it, any microscopic critters would perish in the oven.

That being said, if you decide to get a Nutramill, let me know and I might be able to buy the old one from you!



subfuscpersona's picture

I was going to suggest milling something in it but eDogg beat me to the punch. At 1/2 inch, the larvae should be shredded by the micronizer.

I would suggest using some cheap white rice instead of wheat to clean the unit. Save yourself a few pence.

BTW, I thought the larvae photos were great. Why do you just happen to have a digital microscope in your home? Geez, now I have to get one of those just for similar emergencies.


suave's picture
PaddyL's picture

But thank God you didn't just post the pictures on the site or I would never have come back here!  I didn't go and have a look on the links you posted; just the thought of those wigglies makes me flinch. 

qahtan's picture

I would say , "very nasty".   qahtan

cordel's picture

What are the parts of the grinder made of?  Are there any that would be damaged by heat?  I think, if not, that I would either pour boiling water through the machine, or better still, bring it up to 325 in your oven, then put some rice or something of that sort through it, after it is cool and dry.  Your main aim would be to be sure you don't eat anything that has been contaminated. Really, bugs are part of life.  I prefer them outdoors, but anything you find in flour icky as they may be, probably are found in ground flour as well as whole grain.

plevee's picture

I agree with the prior suggestion to grind something disposable , possibly a couple of times. Then inspect the machine & the flour & if they look OK just use it regularly.

Whatever they are they're going to be ground up & baked -  there are probably more than a few pulverised insects in any batch of flour you buy. You could say it's added protein :)) ?


verminiusrex's picture

I used to deal with pests in bulk pet food by putting it in the freezer.  If you have the space in a chest freezer, or if the weather in your location drops below freezing you can leave it covered on a porch or in your car.  I'm just assuming that freezing will kill whatever bugs are left, I'm no entemologist.  Be sure to let it warm up to room temp before messing with, cold can make parts brittle.

UncleCharlie's picture

The problem with this old "Magic Mill" is it has a huge electic motor, and otherwise a lot of wood panel/parts and it's hard to get into all the nooks and crannies to clean it.  My biggest fear is those small particles all over might be eggs that would hatch under the right conditions.  Nothing appears to be damaged, but I think I may put this one 'out to pasture' and just get a Nutramill.


I got the digital microscope for seeing small circuit boards, stamps, etc., and they are pretty cheap from this EBay site.  Also gives ability to record a movie and/or snapshot.


Be glad I didn't post the movie of these guys moving all over.  They look like they want to eat your brain!  LOL!


Thanks for that link of

UncleCharlie's picture

Here's a couple other high res images of the Magic Mill with things taken apart about as much as I can.  You may have to enlarge images to see the small white eggs or exoskeletons.

Magic Mill-1

Magic Mill-2

Magic Mill-3

Magic Mill-4




mcs's picture

How about blasting that main area with the grinding wheels with water from a pressure washer?  I would think if you kept the pressure at 1500 psi or below, you'd be able to get out just about everything without ripping off all of the finish on the inside. 


UncleCharlie's picture

Not a bad idea, I'm just afraid the water would get into the motor though.  I wish I had a compressed air sprayer.

Rosalie's picture

I don't particularly like to see miscellaneous critters in my food, but they are just added protein really.  If it were me, I would do my best to clean the machine (use the other suggestions, maybe turn the machine upside down over the sink and bang a little on the sides).  Then I'd run something cheap through it and throw the meal out.  Anything that happened to remain would be killed/sterilized by baking the bread.


beeman1's picture

You could put it in a large plastic bag with some dry ice. Let it vent a little and the CO2 should kill them.

tananaBrian's picture

Ditto on the CO2.  It only takes a 10% CO2 atmosphere to kill eggs, larvae, and adult bugs.  If it were me, I'd figure out how to disassemble it, then I'd brush it, wash it, dry it, then put it in a bag with CO2 for about a week.  Some bugs can take a couple of days to die, e.g. hard little eggs that don't absorb the CO2 as quickly.



Mini Oven's picture
Mini Oven

Do the nasty!  Put the whole thing into a large bag, set it outside (open porch or extremely well ventilated area, not a garage) and away from pets and kids.  Then while outside (use rubber gloves) mix about 1/4 cup chlorox with 1/4 cup amonia cleaner (or any cleaner that warns about mixing with chlorine)  and set the open jar inside the bag.   Close up bag tightly with lots of air and let the chlorine gas kill everything creaping in the mill.  Open the next day.  Dilute the volitile cleaning solution with lots of water and pour it over any stains on the driveway or patio or well vented area, Rinse well.  Uncover the mill and let it air out for a few days. Turn the bag inside out and hang up outside to air out for a few days too.   Use canned air on the mill like the electronic pros dust circut boards (I buy canned air to dust a big stupid carved ship my hubby insists on keeping)  to blow out webs and such.  Some vacuum cleaners can be reversed, meaning the hose can be attatched to the filter and used like a blower.  With a small attatchment the air blows out stronger.

What I don't know is if the gas will bleach the wood or cloud the varnish.  With airing and sunshine the chlor smell will soon be gone in a few days. 


UncleCharlie's picture


I did decide to exhaustively clean this old Magic Mill.  I used a canister vacuum and a number of flexible adapter hoses, small brushes, and blowers.  Then left it outside protected in some 0-5 F cold days.  I bought it back the the 1970's when I lived in Bloomington, Indiana with a Bosch Mixer, and a copy of the old book "The Magic of Wheat Cookery" by Lorraine Dilworth Tyler which is still in perfect condition.


I don't know if my mill is before or after the one pictured in this book, similar to your adjustment in the back, but I still have the yellow pamphlet saying it is a "Limited Edition Mini Mill"  Stones are listed as 5" diameter, 1" thick with adjustment knob on front.  Has a 5 Cup stainless flour collection pan, and 1/2 h.p. motor, and after all these grinds a wonderful coarse or fine textured wheat.


I have fallen in love with it all over again....made 3 batches of bread with hard red winter wheat, and spring.  People have never tasted bread like this, as I remember it being the same praise all those years ago.


I bought wheat from & also another from which I have not started using yet.  Not sure where you all like to get quality wheat from, or if that is against the forum rules to ask.


I just ordered those traps from King Arthur's.  Thanks very much for that & the Bay leaves.

rainwater's picture

I remember watching a video for an "organic" grain and mill company....might have been "Deaf Smith" mills. ....don't remember. I do remember the part of the process that "shakes" the grain over a screen, or screens of different gauges before milling. Lot's of bugs come shakin' out....lot's of bugs. It's organic. Maybe the bugs are why organic flour tastes better... :)
I guess there is no really true vegetarians out there...we get bugs in our food, it's a fact of life. Our closest animal relatives (monkees and apes) get most of their protein from bugs.....

UncleCharlie's picture

Yeah, good points.  I was more surprised at how long this mill had been sitting unused, undisturbed.  Never saw any moths, never saw any larvae around it.  Yet the 6-10 of these little guys were as alive and mobile as any bug.  This was the middle of winter, so mainly was surprised at their longevity and trying to identify them to know what I was dealing with.


Put some of those King Arthur's moth traps in a few key places, but mainly enjoying the wonderful bread again.


Thanks everyone!

UncleCharlie's picture

Well since I posted those images, I have made at least 100-200 loaves of bread with no ill effects, and no return of the evil invaders.  So, all is good.

yozzause's picture

go along to your local mechanics workshop and get them to use the high pressure air hose they may even be able to take it apart for you.

Department of agriculture will probaly be able ID the bugs and even give you a treatment for them, even have the facility to  deal with them for you. 

GOOD LUCK  (all 200 of us posters would like to know of the outcome or when the online bidding for the infested mill will start)

actually you should send it to australia for a holiday AQUIS our quarantine service

would have a field day it would be iradiated and be squeeky clean or they might just destroy it too

regards Yozza