How are whole grains for home milling treated for granary pests?
How are whole grains for home milling treated for granary pests? And what implications does this have for the home baker?
Here's what my internet research tells me:
Mills used to use Methyl Bromide, a carcinogen, to fumigate flours. Now, they seem to use a combination of Sulfuryl Fluoride and heat. I don't know if mills use these processes on just flours or also on unmilled grains. An alternative organic method seems to be to spray the grains with diatmaceous earth, a ground up prehistoric arthropod shell derived from the sea that kills insects mechanically. This method is considered very safe in the gardening community, though it becomes ineffective when wet, and is basically just a form of calcium.
If granaries use heat treatment on flour, what are the implications on whole grain nutrition? Of what importance are the enzymes that will surely be killed by 140 degree F heat treatment? (sometimes mills use a lower temperature, but I saw this temperature in industry literature as the "high end") Surely we're going to kill off the enzymes anyway when baking. I know living enzymes can cut fermentation in half (not always a good thing), so there's at least some impact. Do the enzymes also help free up nutrients during the ferment?
I am not a fresh ground zealot, but I do see strong evidence that whole grains, store bought or ground at home, are more nutritious, and pesticide residues in flour may be another reason for grinding your own. I just don't understand what's used to control pests in organic grains, or what benefits/complications these treatments might have for home bakers.
Any ideas?
Joshua in Seattle
The only crops that I have used Diatomaceous earth aka fossil shell flour on were cabbage and broccoli to control cabbage loopers. Some farmers that have livestock feed DE to their animals to prevent parasites in them.
The grain is run through a grain cleaner before it is put into the bins to separate out weed seeds, chaff, stones etc and then cleaned again at the bagging facility before it is bagged and then I personally sift the grains again before I process the grains into flour to make sure that there are no kernels of grain with the chaff still attached. While this isn't necessary it is just an extra step that I like to do as I am a bit of a perfectionist.
I would like to say that while the verdict may still be out regarding the nutritional value of organic versus conventional foods the main reason that we choose to farm using organic methods is that we have seen first hand the damage that the use of chemicals does to the environment. What goes into the soils and water eventually gets into the food supply. We have seen whole lines of mature trees die all at once on a large conventional farm in this state due to the overdrift of chemical sprays over the years on that farmers' fields. A family friend raises bees commercially in Wisconsin and recently had 200 hives of bees killed from a spray that the farmer there used on his soybeans and which came in contact with the bee hives. Chemicals are poison-period and we choose not to use poison on our crops.
Some final thoughts - there are different methods of harvesting grain crops. We use a straight head to cut the grains that go through our combine which means that our grains are cut while they are still standing upright and after they dry naturally on their own. Some farmers use the method of swathing their grains first which means cutting them down in rows and letting them dry on the ground and then they use a pick up head that picks the dried swaths up off of the ground which are then run through the combine.
We prefer to use the straight head method because this also helps to prevent unwanted dirt from getting into the grain.
Organic farming methods can vary from farm to farm just as conventional methods can vary from farm to farm. There are many variables to both methods and within both methods such as soil fertility, climate and general farming practices. I think that organics shouldn't be lumped together in one lot due to these variables.