The attached photo was taken of a Mini-Pops brand popping sorghum bag. For those that know how grain is processed, stored, shipped, or even how fields work.. this isn't a shocking thing.But it is something to be aware of.
All grains are often grown in fields where other grains have grown (causing plants to grow from seeds of the last year among what was planted) and if the grower isn't super OCD about removing stray plants from these fields, the seeds of stray plants can make into the harvest. These harvested seeds are often shipped in the same trucks and stored in the same silos that other seeds used to be in, or even so close to other seeds as to pick up a stray seed from another plant.
Most places that use grains have a quality control group that sorts through the seeds - even if it's a robot or sieve - and removes those that aren't the right seed. But as you can see, it's not always 100% effective.
This cross-contamination may also help explain why many of the super sensitive corn allergic persons must avoid all grains, though there are other reasons why that may be the case.
For most people, the trace amounts that escape the sorting/quality control process for flours and whatnot are not usually a big deal as we're talking about a very very small amount that is usually divided among a large amount. For example, one kernel of corn in 200 lbs of flour.
However, finding one kernel in a bag like this is scary to the corn allergic. So please, if you buy whole grains of any kind, please please make sure to sort through before preparing/cooking and we also generally advise rinsing before use to remove any grain powder on the outside. Rinsing grains for popping though will probably interfere with the popping process, so proceed with caution.
