Storing whole grains, flours and other ingredients
for bread making

The gold standard storage method for whole grains, flour products or other dried pantry produce (eg. whole or ground seeds, almond meal, legumes, beans etc.) is to keep them in airtight containers or bags (hopefully re-usable) inside a fridge or freezer.

But I know that not everyone has the space to do this, so I’d like to go through the most important factors that impact on grain/flour storage to help you make the best decision about how to store your ingredients in your own situation.

> Information about home milling and Mockmill links
> Information about grain suppliers in Australia

UPDATE - a new video on this topic!

Written content continues below :)

Climate and temperature

If you live in a hot and humid climate, your flour and grain products will naturally deteriorate faster than if you live in a cool and dry climate. Firstly, warm and humid storage conditions increase the rate of spoilage and rancidity in pre-milled products such as ground seeds, nut meals and wholegrain flours that contain all the parts of the grain including the bran and germ (the very nutritious and oily parts of the grain).

Secondly, all whole grains (and many flours/other pantry produce items) have the potential to contain weevil eggs that are invisible to the naked eye, but if present, will eventually hatch given enough time under the right conditions.

Weevil eggs on your grain are not necessarily a sign of poor quality or poorly stored grain (live weevils, larvae or weevil damaged grain are though). Weevils of various types are a commonly occurring beetle species that should (in my opinion) be expected to be found in all grain crops to some extent. So it is up to the individual consumer and the growers/suppliers of our grain to store these products in a way that prevents weevils from hatching in the first place.

What is a weevil? (Wikipedia)

Time

You can avoid the potential issues of spoilage, rancidity and insect infestation by reducing the amount of time your grains are in storage. If you don’t have space in your fridge or freezer, try to buy smaller amounts that you will use up within a shorter period of time. This will greatly reduce your risk of a weevil outbreak or rancidity of your pre-milled whole grain flours.

* It is interesting to note here that roller-milled/refined flours (bread flour and all-purpose/plain flour) have a much longer shelf life due to most of the bran and germ (the oily, nutrient-rich parts of the grain) grain being removed.

It is recommended to use pre-milled whole grain flour products within six weeks of their milling date. Many store-bought whole grain flours will have been in storage for much longer than this, but if they are all that is accessible to you, buy amounts that you can fit in your fridge or freezer and place them there as soon as you get them home, or otherwise use them as quickly as possible.

Manipulation of time and temperature

You can get clever about grain storage and use different methods in different seasons. I find that my whole grains store perfectly well at room temperature, in large plastic sealed buckets throughout the cooler months here in Brisbane. It is only during the hot summer months that they appear to be at risk of weevil outbreak.

I have also heard many home bakers report that freezing grain for a week or two kills weevil eggs, after which the grain/flour products can be safely stored at room temperature. Since my one weevil outbreak I haven’t had the courage to try this!

This article from Iowa State University advises that ‘all stages’ of rice and granary weevil development (presumably including the egg stage) are killed if whole grains are stored at 0°F (minus 17°C) for three days.

What to do if you find weevils?

It’s a worrisome day when you spot a weevil in your flour or grain storage. I’ve only had them once, and once is enough!

The best thing to do is discard any infested grain or flour products, especially whole grains because the grain may look okay on the outside, but may harbour unhatched weevil larvae growing inside the grain! (eeww).

If you have a garden then composting the whole lot back to the earth is ideal, but if the garbage is your only option, make sure you wrap it well and remove it from the house asap.

If you see a weevil crawling anywhere in your dwelling, squash it on sight or remove it to the outdoors immediately. You’ll then need to check your cupboards thoroughly, for there is no such thing as a lonesome wandering weevil. There will be more!

If you can locate a single source of the infestation, and you think you have the critters contained, just discard that product and check the rest of your pantry thoroughly for any rogues that may be wandering about. If you first discover weevils crawling on your benchtops, or roaming about freely inside your cupboard, they are probably widespread and you may need to remove everything from the cupboard and check for particular bug-friendly hot spots (eg. pasta, rice or breakfast cereal packets) and remove any infested goods. Clean the cupboard thoroughly, including vacuuming out nooks and crannies, wiping away any dust with a damp cloth, and paying particular attention to corners and edges.

After my one unfortunate weevil event, I have been quite strict in my approach and only store dry goods in my pantry that I know are fresh and that we can consume within a month or two. The danger zone is when you have old pantry produce sitting in the back of a cupboard for months on end in warm temperatures, so avoid that at all costs.

How exactly do I store my grains and dry pantry goods now?

I am fortunate to have a solar-powered house and a little corner for an old spare fridge and small chest freezer, so all of my whole grain and bulk pantry items are stored there now. Some of my soap making ingredients are stored there too.

Because of this, I tend to buy as many items as I can in bulk and the large sacks of grain go straight into the freezer as soon as I purchase them. I used to decant my grain into smaller bags, but have found it much easier now to leave them in the large sacks, make an opening in the top of each one, and scoop the grain out as needed into smaller tubs that I keep in my kitchen cupboard for milling. Each of these tubs only holds about 3-4 kg of grain, so it is always fresh and bug-free!

Things like pre-milled flours (some of which I mill myself ahead of time for general cooking use) and ground linseed/flax meal, beans etc. I store in my spare fridge as well. On the other hand, some things like brown rice, lentils and rolled oats never make it to the fridge or freezer. They are stored in the pantry at room temperature because they are consumed often and purchased regularly.

The main thing I avoid is letting any grain, flour, or other dry goods pantry product (even pasta!) sit in my room temperature pantry for any longer than a couple of months. It is only when these products stay in storage for months on end, in warm conditions, where weevil outbreaks and other spoilage issues are a risk.

A good tip for using grain from the fridge or freezer (avoiding condensation issues)

If you do store your grains in the fridge or freezer, make sure you bring them out of the cold environment in enough time for them to return to room temperature before milling. This is particularly important for those of you (like me) who live in high humidity environments.

In hot and humid climates, any item that is colder than the ambient air temperature will develop condensation on its surface. To avoid your grain becoming wet, keep it sealed in a bag or container as soon as it is removed from the freezer, until it has returned to room temperature. Any condensation will then form on the outside of your container (which you can later wipe off) and not on your grains which are best kept as dry as possible.