We have noticed that the grain in our fine smoking dust is not always uniform. This can cause certain mixes to still contain too large pieces of wood. If you use these in your cold smoke generator, your coil may not burn up completely. This is because the smoldering effect stops when there is a too large grain in the coil. Since these larger grains are not found in every bag, it is difficult to block a complete production batch. If you have received a bad sachet, we will gladly send you a new one.