The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Flour beetles?

jhegg's picture
jhegg

Flour beetles?

OK, so I just ordered from the KA website three 25# bags of unbleached white flour with free shipping for $20.00 a bag (it costs me about $7.00 for five pouns locally). Afterwards, the ladies at work said it would get all "buggy" before I could use it. They said "flour beetles" get into the flour and ruin it. Just what are these "flour beetles", where do they come from and how do I defeat them?

Jim

Faith in Virginia's picture
Faith in Virginia

The larva is in all flour so if you let your flour sit to long they hatch and then you have beatles.  The only way I know of is to use your flour quickly or put it in the freezer.

Hope that helps.

 

sue cardiff's picture
sue cardiff

That is one of the strangest things I have ever heard. Can you provide any kind of reference or back-up for this claim?? Frankly, I think this is a myth.

sue

Ford's picture
Ford

You have been VERY lucky, if you have nerver had an infestation of these pests!  I noticed them about three years ago in my house, and I have not gotten completely rid of them, yet.  I now do not see any products infested with these insects, BUT I do see the moths flying around every now and then, so I know there is an infestation somewhere.  I seal opened boxes of cereal, flour, rice, etc in Ziplock bags.  The whole wheat, cornmeal and other whole grain cereal in the refrigerator, or the freezer.

This is no myth!

Ford

jhegg's picture
jhegg

Faith,

If I put it in the freezer, do  I need to seal it with plastic wrap?

Also, doesn't the grinding destroy the larva?

Jim

Faith in Virginia's picture
Faith in Virginia

I would put in a plastic bag and try to reduce any moisture  from the anti frost cycle affecting the flour.

Sue here are just a few.

http://www.ncbi.nlm.nih.gov/pubmed/18608514

http://www.thekitchn.com/how-to-prevent-get-rid-of-grai-140955

http://ohioline.osu.edu/hyg-fact/2000/2089.html

There are many others search    Sitophilus granarius

Mini Oven's picture
Mini Oven

mealy bugs, old flour, flour bugs

All raw grains and cereals carry them.  That is why buying flour (products from flour and grain mixtures) too far ahead of your needs can end with a healthy batch of added protein.  A good sieve will also remove them.  Problems arrise when they reach adulthood and many will fly and crawl around into other foodstuffs and soon everything is invested with them.  That's what storage bins are all about and rotation of stock and expiration dates.  Oh, and they can eat thru plastic bags and cardboard.  Some sure signs that they are in your cupboard are dust inside noodle boxes, chewed corners of boxes, extra dust around such boxes and fine webs and tiny moths coming from "nowhere."  

 

zanhilo's picture
zanhilo

The moths (sitophilus granarius) that are found most commonly in flour in your pantry can come from the field, it can be picked up in the grain bins where it is stored before it is sold, or picked up in any step of the milling process or even in the store where you buy it. Common stuff, they are a part of nature, and even if you eat them, completely harmless.

Even if you see no evidence of infestation in the store, you can still get them. What is in the flour are the eggs of the moth, as the larva and adults can easily be sifted out of the flour. The eggs are so tiny that it is nearly impossible to get every last one.

However, there is an easy, easy way to prepare your flour for long-term storage, and that is to freeze it completely for at least 24-48 hours or longer if you can. The lower below 0 deg F the better, and the longer you can hold it there the better. The low temps cause ice crystals to form in the eggs, which burst and destroy them. Larger bags take longer to get completely cold to the core. I like to leave mine in the deep freeze for a week. You can leave your flour in the paper bag, or wrap in plastic to help minimize freezer odors. Once you remove it from the freezer, store in an airtight foodsafe container. Five gallon foodsafe buckets are great, as long as you use a mylar or plastic liner, as it can help to seal it tighter. Five gallons will hold just about 25 lbs of ground flour. White flour can keep for years, whole grain flours keep for three to six months depending on temp but can go rancid. You might want to just store the whole grain and grind as needed, as at the right temp & humidity it can keep for centuries.

There is no pesticide approved for food use on or around flour. So once you find them, freeze then sift to remove larva & adults. Sticky traps can reduce the occurance of the moths in your pantry. Store all your grains, convenience foods, and cereals in airtight thick plastic (cambros or equivalent) or metal containers.

Garbage bags are NOT food safe! Pesticides can coat the inside or be incorporated into the plastic, so it can and will leach into the food.

Good luck!

Grenage's picture
Grenage

Flour weevils; I've never seen them, and I've had a 25KG sack of flour knocking around for a year!  Yes you can get them, but it's hardly guaranteed.

I've heard of some commercial places using the flour regardless.... I personally wouldn't.

Yerffej's picture
Yerffej

Bay leaves are a very effective repellent for grain moths.  Wherever you have grain, cereals or anything related, sprinkle a few bay leaves around. 

It works,

Jeff

zanhilo's picture
zanhilo

Yes, bay leaves work very well. I've used them as well, but after a few months in storage, I find the flour has a bay leaf flavor. So I chose to freeze it, then seal it in a container until I'm ready to use it.

The reason I keep flour and grains so long is that I work/live on a wheat farm. It's cheaper to hang on to the wheat and grind the whole wheat myself instead of sending it through the "system" and then buying it for double or triple at the store! About the only flour I buy anymore is cake flour.

Yerffej's picture
Yerffej

Aware that bay leaf flavor transfer is a possiblity, I sprinkle the bay leaves near and around but never in the flour.

Jeff

PClark's picture
PClark

they will drive you crazy getting rid of them. I got them in my pantry and it took a long time to find the reason and rid myself of them. I freeze all flours and meals and if I have room, I just leave them in there. I keep AP flour in a sealed container in the cabinet but all others are in one of  the freezers. I bought those sticky Pantry Pest traps which worked well for the moth and then I did a complete search of the kitchen. Turns out they were in a boxed product with a plastic bag inside, never been opened. And it was a mess. I don't remember what it was, but something to do with nuts. I remembered thinking that I didn't know they would like nuts, but they did. My nuts stay in the freezer too now, and we just keep a Mason jar full in the cabiner. I am paranoid about the little things. I do wrap my flours in plastic wrap before freezing.

Mini Oven's picture
Mini Oven

I remember we had to pull the pantry apart and seal all the plywood shelving and supports by painting and sealing them before she would put anything into it.   They were hiding in there sure enough.   Not only in the wood but between the shelves and the walls in all the rough edges.

jhegg's picture
jhegg

Thank you to everyone for your comments. I finally realized that the pests in our house last fall were these. The source was a vase full of pheasant tail feathers. Once we got rid of the feathers, they finally died out. Just to be on the safe side, I'm packing by flour into large zip-lock freezer bags and storing them in the freezer. Thanks again to everyone.

Jim

Susan Kline's picture
Susan Kline

Bay leaves were also my grandmother's preventive, but I was concerned about the flavor going into baked goods.  I stored my great-aunt's things in an outdoor public storage facility and discovered that I had included her flour which was in a very large metal pretzel can.  That flour was in there in all kinds of weather for more than a year and I was amazed to see that it was completely bug free!  I used that can for years and just recently got rid of it only because of its size.