Flour doesn't create weevils. Weevil eggs do. They're a kind of beetle. I've had them, or something like them, in bulk bin grain, but never in a bag of major mill flour. A smaller, less industrial mill, might not be able to get all the eggs out. There are also spice beetles, and similar pantry pests, that can hitch a ride into your kitchen and which are very hard to get rid of. The eggs can get in at any point, the mill, the shipping, the store, or your house.

Plastic and glass are your friends. Beetles can eat through paper and cardboard. If you're concerned, get an oversized jar, like a pickle jar, for your spare bag of flour, or a food grade plastic bucket. Secure lids, of course.

There's something else to consider, however. Flour can go rancid. Whole wheat flour has more natural oil in it than white, and can start to go almost immediately. That's a big reason so many people have started milling grains at home. One of the reasons so many wheat doughs, both homemade and industrial, call for honey or other sweetener is that it masks the rancidity. White flour has a much longer shelf life. You don't know how long it has been in the warehouse, store, etc., however. I put my airtight canisters in storage during my kitchen remodel, but it went a lot longer than planned (tile issues) and three months became most of a year. The flour went off. I never plan to keep a back up bag of white flour for more than three months, and I always give any of my canisters a sniff before using.

I should of mentioned that I had microwaved a cake that I made with white flour that i kept in a plastic container. I ate a couple of slices innocently one day and the very next day when I went to my microwave oven, where I stored it, I saw minute insects moving about and noticed small holes in the remainder of the cake, which I discarded immediately and cleaned out that microwave of the infestation. Now, i have to believe that those 'insects' originally came from the flour, or the warmth of the oven produced them from the cake. I was just wondering how can one tell by looking at the flour before reusing it if its infested with crawling things? I would think with the whiteness of the flour it would be difficult to see, but not in the oven.

I had an old Tupperware container to keep my flour.

I was extremely surprised to see the weevils had eaten through the plastic.

A friend told me to put any new bag of flour in the freezer for at least 24 hours to kill the weevil eggs.

That was 20 years ago and since freezing the flour, no more weevils.

I've been freezing grain products for years. I leave them in the freezer for several days or more before storing in a tins or jars

I inherited all sorts of pantry and home pests from the previous owner. Even though i started with fresh when we moved, i had many problems for a couple years. They can come into the home from any spice or flour. Even purchased so-called-fresh. I give a new flour or spice a freezer week or month. But also have started grinding my own and purchasing from suppliers that i've researched for freshness. Bugs are in everything and not a health issue but seeing them and seeing herbs clumping with bugs is not very appetizing. A time in the freezer will help.

NYC has some charming spice houses i used to frequent. Seeing cats curled up in the open spice bags turned me off a bit, lol.

I find it very hard to believe that insects would survive the baking of a cake. Infestation before and after baking maybe....

This reminds me I have two huge bags of flour to rebag and freeze. I made a couple hundred pitas for someone who was catering a gathering. I got paid in ingredients including local flour.

BUT note to self - new fifty pound bags of flour should be a FALL purchase for me. I have no shortage of cold storage fall winter and spring. Right now on the other hand I have plans for every nook of my freezer. And my porch is definitely not chilly.

I took a class on "Pantry Pests" many years ago at the Co. Extension Office. The nice entomologist was happy to tell us the weevils (and there are several varieties than you can have in your food) are edible and a good source of protein. Especially important for third-world vegetarians. It's how they consume the all important B12 often missing in vegetarian/vegan diets. At a class for vegetarians, our instructor was a Seventh Day Adventist; and she suggested you go for a bike ride and swallow several gnats when you biked through a swarm for your B12.

One of the biggest sources of pantry pests in homes are bags of dry pet food and bird seed, so when possible, store them outside your home or in air-tight containers. Pet food and bird seed are not regulated and stored like people food, so are easy targets for pantry pests.

I've been storing hundreds (and hundreds) of pounds of grains/seeds/beans for decades in our food storage room and kitchen/pantry and have never had an infestation, but I use vacuum-sealing as my preferred method of food storage for dry goods. Once the oxygen is removed from the storage container/bag, any live pests die, as do any eggs.

Science has proven such things as using bay leaves, 6-penny nails and chewing gum are NOT effective against pantry pests. "The only instances where they have been effective are when NO insects were initially present in the food." (Source: Utah State University - who put a LOT of food to test as part of the LDS Church food storage program). I have also read that you can use Lysol - spray and wipe cabinets to avoid pantry pests, but not sure if there is any science to prove that either.

Those of us who store enormous amounts of dry goods will use vacuum-sealing - whether it's with a FoodSaver type vacuum machine, or mylar bags/canning jars and oxygen absorbers.

If you want to vacuum-seal flour, it needs to be in a jar or canister where it will remain free-flowing, NOT in a FoodSaver plastic storage bag where it is packaged tightly packed. There is a small amount of moisture remaining in flour, so when it's vacuum-sealed tightly in a plastic bag it can start to smell like mildew, and can potentially develop mycotoxins (like aflatoxins), so use a vacuum-sealed container where it remains free-flowing and still be oxygen-free.

When I was purchasing flour in bulk, I always purchased it in large quantities when school started in the fall (back-to-school cookies and the general increase baking with cooler weather + enough for holiday baking) and tried to use it by March. I always tried to use commercial flour within 6-months of purchase, and no more than 12-months if it was frozen. Usually having a bake-a-thon for St. Patrick's day with traditional Irish breads and goodies to use all but about 5# (enough to get me through the summer). I vacuum-sealed the flour in 1/2-gallon jars.

Freezing is also a good method, but it doesn't always mitigate the eggs. I never had enough storage space to spare for large quantities of flour and dry goods in my freezer, so I've successfully stored them using a FoodSaver since 1986. The five enemies for all stored food are heat, light, moisture, oxygen, and insect infestation.

-Grainlady

Just recently I decided to make bread and pulled down my Tupperware type container of bread flour. On opening it you could tell something was wrong because of all the microscopic dots in the flour. It looked like a very fine grey pepper was in it. Of course, it was weevils. I haven't had trouble with them in more years than I care to count and the only thing I can think of was I was out of bread flour, bought a five pound bag and immediately dumped into the bread flour container without freezing it first. It was immediately disposed of and the container washed in bleach water then in regular soapy dish water then allowed to dry out naturally. I always put my newly purchased bags of flour in the freezer and have several in there now, but must have slipped up on that bag. Nasty little things and I don't want B12 bad enough to eat them.

Re plastic, when I recommended it above, I was thinking of hard plastic canisters, like polycarbonate. They can't eat through that. :) It's the softer, textured plastic that's vulnerable.

Grainlady, thanks for the info on vacuum sealing re pests. I didn't know that. I recently stored some wheat in food buckets, but I'm not pleased. I think if I vacuum seal and put the packages in the buckets, it'll be better, with the added benefit of killing any wiggly things. :)

plllog- All the hard grains I purchase in bulk amounts (in paper sacks), like wheat, are vacuum-sealed in FoodSaver bags in 5# amounts and stored like sheets of paper in a file cabinet in large plastic storage tubs, which line heavy-duty storage shelves. Those that were purchased in buckets are vacuum-sealed and placed back into the bucket. I've used this method since I started storing whole grains in the 1980's. No "wiggly things" to date! Small amounts of grains/seeds go into canning jars.

Thanks, Grainlady!

I'm just a once in a while baker (mostly in the winter,) so I store all my flour in the freezer. Seems to work well, no buggies.

Since I'm always wanting to improve where practical: when storing in the freezer, the paper flour bags, especially when they've been out of the freezer for 5 mins or so, do seem to stay a little moist. Is it better to put the flour into a different container, or will the flours do ok in the paper packaging (which are inside of supermarket plastic shopping bags to keep spills contained)?

Regards storing in plastic containers, I've been told by a pet food rep that storing pet food in a plastic container is a bad idea because the plastic absorbs the oils, which go rancid, and will affect the flavor and quality of the food. I would assume, then, that would happen with flour as well. I'd think that hard plastic such as what Plllog suggested, wouldn't be as absorbent, but those soft plastic containers would be a problem.

I have a freezer full of bags of flour that are probably well over 12 months old. I think I'll discard them and start with fresher flour for the fall.

Today I'm emptying my kitchen, cabinets, drawers, and all, because it's become infested with ants and other pantry pests. Everything is getting a thorough scrubbing. *sigh*

Sally

Rgreen, Yes, it's better to put the flour in something air tight for storage, even in the freezer. Remember to fluff it up before measuring. :)

Ty plllog... I have a number of ceramic containers with rubber gaskets that were given out as gifts from a coffee club to which I once belonged. Perhaps it's time to dig them out of the closet and put them to good use. I'm sure I'll need to be careful using them around frigid temps, but I will definitely benefit from one less box in that over-crowded closet.

Thanx!

rgreen48 - If you are using glass storage containers in the freezer, it's best to use tempered glass, like canning jars, which are designed to be used in the freezer. Place the jars inside a sturdy plastic basket and put cardboard between the jars so they don't knock against each other. I've had a glass jar shatter in the freezer and there's nothing less fun to clean-up. Not all glassware is designed to be used in the freezer, and the rubber gaskets may split/crack when stored at freezer temperature. I'd use the ceramic containers for kitchen/pantry storage since they are air-tight, not the freezer.

sally2_gw- You are correct about fat and plastic. It's one of the reasons people should avoid storing bulk dry goods in used plastic pails they get from bakeries/restaurants that contained any type of fatty ingredient - like frosting, shortening, etc. We have recycled 50-gallon plastic food shipping containers and even after 8-years of being used as rain barrels, you can still smell the former fatty contents of the containers. Fat actually bonds to the plastic and is impossible to remove completely. At some point, under the right conditions, the bonded fat will go rancid and the rancid smell can affect whatever is stored in the pails or plastic containers.

-Grainlady

Thank you Grainlady. Since I cannot verify that they are tempered, I won't be using the ceramic jars. :-(

I don't keep food long enough, nor do I have the space for using the ceramic canisters as pantry storage. Oh well, back in the box for them.

I buy 5 lb bags of flour which go directly into a regular plastic grocery bag, tied up, and then immediately into the freezer the minute I enter the house. They stay there. All baking supplies,esp nuts, bin stuff, grains, go directly into the freezer. When I need flour I put it into hard polycarbonate airtite containers and store at room temp. In my baking center drawers.

Most other baking and grains and bin food go from the freezer to the fridge in glass jars or hard plastic or double wrapped plastic. Grains wind up in room temp storage eventually. Ap and bread flour wind up in the room temp baking center but all other flours stay in the fridge after the long stay in the freezer. Nuts always in fridge or freezer. So far so lucky,