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In the Lab: Quality

Ever wonder what quality checks at a hops mill look like? Here at Mill 95 providing a quality pellet is a top priority. We take several steps to ensure that we are providing the highest quality pellets to our customers possible, from receiving bales to packaging the pellets.


  • Equipment is calibrated daily to ensure accuracy
  • Bales are weighed on a dual-certified truck scale as the truck arrives
  • Before the bales are unloaded there is an initial moisture check (if too many bales are out of spec the truck is rejected)
  • As the bales are unloaded they are lined in the shade under the breezeway
  • Moisture is checked on a minimum of 2 spots on every bale
  • Every tenth bale has a core sample taken to supply a composite sample to send to 3rd party labs for MRLs (Maximum Residue Levels) and COAs (Certificate Of Analysis)
  • Every tenth bale has its temperature checked and recorded
  • Brew Cuts are taken from every 25th bale for Brewer Selection
  • Every 4th bale is hand-tried to ensure the quality of the cones
    • Hand-triers look for bug/disease damage, off aromas, coloring, and verify moisture. Anything out of spec is returned to the supplier
  • Bales are then labeled then taken into the cooler as soon as tests are completed to preserve the freshness of hops


Once MRLs are received and meet US, CODEX, and EU regulations we start the production process

  • Lab equipment is calibrated daily to ensure accuracy
  • Bale Breaker: As bales are being pushed into the bale breaker, we monitor the heavy drop to ensure that any foreign material is caught, weighed, and noted
  • Rare earth magnets are used to collect other metallic foreign material throughout the process and are checked at regular intervals (air conveyance, prior to hammer mills, augers from mix tanks, prior to pellet mills, and at the pellet cooler)
  • Pellet Mill: Once the pellet mill is started a thermal imaging gun is used as a quality check to ensure the temperature of the pellets is within specification. At this point appearance of pellets is also checked.
  • Packaging: Once packaging has started, we perform tests on 3 foils per pallet (1540 lbs)

Every bag pulled:

  • Weighed on a certified scale
  • Seal checked using a vacuum chamber
  • O2 test
  • Density checked
  • Composite samples are taken for our library and to send for final COAs

Every 3rd pallet foils are pulled have two additional tests:

  • Fines percentage calculated: this lets us know if we have too many fines in the bag and if we need to adjust the grind size or speed of the pellet mill.
  • Solubility: A pellet sample is put into 114 degrees Fahrenheit water. Solubility tests verify the density and allow us to see how long it takes for the pellet to dissolve as well as identify any off aromas or non-conformities in the pellets.

Regular Quality Checks:

  • Sort through heavy drop bins each batch
  • Pellet Mill: ensures pellets are in spec for temperature and texture
  • Pellet Cooler: Temperature taken at the cooler ensures that pellets are cooling before packaging
  • Clean rare earth magnets: By cleaning the magnets regularly, we can catch any nonconformities quickly
  • Label and QR codes are checked to ensure everything is labeled correctly throughout the run

Each quality step is taken for every lot received and every production lot we run and document. We conform to ISO 9001:2015 standards as we strive to build strong relationships with our customers by providing quality, freshness, and innovation in our products.


Author: Suzy Gibson, Quality Associate, Mill 95

Suzy Gibson is the Quality Associate at Mill 95. Suzy believes that to provide quality products quality work must be put in. She grew up in an agricultural community and has worked with various crops. She holds a B.A in horticulture with goals to get her master’s. Suzy has a passion for all things plant related and a desire to continue to learn. Suzy is excited to continue her journey with Mill 95 and for the opportunity to grow as an employee/individual.


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