The first time I made wheat flour I made about 20 lbs. worth.
I kept it in a poly bucket, just like all of my other dried foods.
I would use it sparingly, since I wasn't used to it and I didn't prefer the taste.
About 1 1/2 years later, I went to a bread making class where the instructor taught that wheat flour only lasts about a week.
I ended up dumping my entire bucket of flour out after I made a loaf of whole wheat bread that ended up turning into a rock after baking (not to mention the fact that it didn't rise).
Several other similar experiences with friends and family over the years convinced me to do the following experiment:
I made wheat flour once a week, over a period of 6 weeks.
Older flour was put into bags and stored in my pantry.
Then I made 6 loaves of bread, each with flour made on a specific day.
Each loaf followed the exact same recipe, had the same amount of rising time, and cooked for the same amount of time.
This is what I found...
Let me explain the numbers, because I should have done them differently.
The loaf without a number was made from fresh wheat flour - ground the same day.
#2 loaf is a week old flour, #3 is 2 weeks old, going up to #6, which is 5 week old flour. You with me?
Okay, here's a closer look:
Surprisingly to me, they all looked relatively similar (size wise).
But they definitely were not the same.
Loaves 1, 2 and 3 (fresh, 1 week, and 2 week old flour) seemed to weigh less than Loaves 4, 5 and 6.
The older the wheat flour was, the harder and more dense the bread.
This was especially noticeable while shaping.
When kneading the fresh flour dough, it was extremely elastic and flexible; very easy to work with.
The older flour dough became progressively harder to handle. It was very difficult to even knead the 5 week old flour dough - it would crack easily and quiet frankly just didn't want to cooperate.
Loaves 4, 5 and 6 also had a drier looking crust. If I knocked my fist on the tops of them, it would make a knocking sound. When I did the same thing on Loaves 1, 2 and 3, the dough would 'give', making an indent of my knuckles, and then popping back up again.
Basically, loaves 4, 5 and 6 had no give.
Here is a shot of loaf #6 next to the freshly made loaf:
You can see by the amount of browning on the side (where I wrote 6) that it didn't rise as much as the fresh loaf did. It also had several cracks and uneven lumps, not to mention the overall dry appearance.
Here is a top view:
This is a really good representation of how dry and unappetizing it looked.
After cutting each loaf open, again, they all looked the same.
Taste and texture were extremely different.
The older the flour, the drier the bread. Loaf #6 was crumbling all over the place. There was no moisture.
Here is a good example of what I mean:
This is me holding a piece of bread from the fresh wheat flour loaf:
Do you see how it bends?
The bread was moist and flexible.
This is a piece from loaf #6:
There is no give, no flexibility, and no moisture... it even started to crack down the middle.
I tried a bite from a slice of each loaf.
They all tasted the same, but the quality wasn't nearly as good, especially when eating from loaves 3-6.
Eating from loaf #6 was like eating week old bread; it was very dry, crumbled easily, and almost had a powdery texture.
Although from the outside, loaf #3 (2 week old flour) looked and felt the same as 1 and 2, it was not nearly as moist or flexible once I cut into it.
There were minor differences between loaves 1 (fresh) and 2 (1 week), probably nothing I would have noticed had I not been experimenting.
So... my conclusion is that wheat flour definitely makes major, unwanted changes after about 1 week of being ground.
The recipe I used is from Pantry Secrets, and can be found here, along with an explanation of ingredients used.
I make my own bread from scratch regularly (with white flour), using Pantry Secret's recipe, which does have some minor changes compared to the wheat bread (all appropriate information is covered in the link above).
My point is, this recipe doesn't call for Vital Wheat Gluten, which is a common ingredient used in bread which helps make it rise better and become more 'airy', if you will.
I don't know what kind of differences it would make if you used vital wheat gluten when making bread with older wheat flour. I am sure it would improve the bread, but I'm not sure by how much.
Another thing to consider is if refrigerating or freezing the flour would make it last longer. I didn't try this, nor will I, because I don't use wheat flour enough to want to store it under those conditions.
Either way, the differences in bread made with flour older than a week were significant in my opinion.
I will definitely be using all of my wheat flour within a week from now on.