Christopher S. Wood, PhD
When Bugs Attack
With the popularity of wholesale warehouse clubs like Costco and Sam’s Club, who’s to say that buying in bulk doesn’t save money and time? Could millions of consumers be wrong? I’m a member and I like pushing around those oversize shopping carts while spending a month’s salary on essentials like a 96 pack of eggs and a 5-gallon jug of milk. My view on homebrewing is no different. Buy in bulk and save money! So when my homebrew club decided to have a bulk grain buy I decided to go all in and purchase enough grain to get me through an apocalypse. My brilliant idea was to spend now to save in the long run. It was genius!
Unfortunately, life doesn’t always agree with my homebrewing schedule and in this case my small fortune of 50lb sacks of malted barley ended up sitting around for a bit longer than I had hoped. In order to monitor freshness and keep pesky bugs from infiltrating my grain I periodically checked each bag for freshness.
Recently, one Saturday morning while preparing to make homemade bread from scratch (Mrs. Science and Homebrews and I make a mean loaf of homemade sourdough) I came upon an interesting discovery . . . tiny little bugs in my bread flour. “Well that was annoying,” I thought to myself. While I threw out the flour and continued to clean my cupboards with vinegar my wife quickly searched for more information on these flour-eating pests. What she found was that these pests were called flour mites and they love flour, wheat, and — barley . . . uh oh! I had just checked my apocalypse-sized grain stash and everything was good, but maybe I should check it again?”
When I opened one of the bags I undoubtedly confirmed that flour mites love malted barley (see pictures). These little suckers were everywhere; on the outside and inside of the bags, on the carpet and even on the walls. It was disgusting. The annoyance of cleaning a cupboard suddenly didn’t seem so awful compared to an infestation in my malted barley stash. Nearly all my grain was infested and ended up in my garbage can. Only a few small vacuum-sealed bags of malt remained bug-free. I contemplated tossing these in the trash as well since flour mites can leave eggs but after some reading I discovered that putting the bags in the freezer kills the eggs (I used the -4 °F/-20 °C in the lab for an added punch). After a week in the freezer I took the grain out and immediately stored it in an airtight plastic bin. Since then, my grain has remained bug-free. This dilemma brings up a valuable point of how to properly store ALL homebrewing supplies, which will be the topic of my next post.
Happy bug-free brewing scientists!Last modified on