Yeast
CellCount counts yeast from a photo of a hemocytometer under your own microscope and reads trypan blue viability, cell size and concentration in seconds. No benchtop counter, no cassettes. One counting protocol is shared across the lab or the brewery, so a pitch-rate number means the same thing whoever loaded the chamber.
Yeast cells are small, so resolution is what matters. The setup that works is a microscope camera on the camera port at its full resolution, trypan blue, and the High sensitivity setting, which is the preset made for small cells. A phone held to the eyepiece works for a check; for the daily count, the camera. Images are counted as captured and never downscaled, because downscaling moves the count.
The three sensitivity settings are High, Balanced, Low. High keeps the fainter and smaller detections that yeast produce; a cell-size gate around your yeast keeps debris and bubbles out of the count. Both are part of the protocol, so they are set once for everyone.
Dilute the slurry so a 1 mm square holds a countable number of cells; the protocol records the factor. Mix one part sample with one part trypan blue, which is the default dilution CellCount assumes.
Load an improved Neubauer hemocytometer under its cover glass and let the cells settle for a moment.
With a microscope camera at its full resolution, or a phone at the eyepiece, frame one full 1 mm square with all four corners visible and the rulings crisp. Do not downscale the image.
Choose the High sensitivity setting, which is made for small cells such as yeast, and a cell-size gate around your yeast. The count, the viability, the concentration in cells per mL and the size histogram come back on the image.
The count, the viability, the concentration in cells per mL from the measured grid and your dilution, and a cell-size histogram, all on the same image with every detected cell marked. Cells per mL and viability are the two numbers a pitch-rate calculation needs, and they arrive on every count rather than on the one somebody had time to do by hand.
Each sample is dated and accepted by a named person, and it leaves as a results document or an export bundle with the images, their overlays and the results as CSV, for the brewery’s own records.
Dilution, which squares, sensitivity and size gate are set once in a protocol that anyone on the team can create and that is versioned. Every count records the version it followed, so a number from the morning shift and a number from the evening shift were made the same way, and a number from last season can be read back knowing how it was made.
Trypan blue is what CellCount reads today: clear cells count live, blue cells dead. If your lab counts yeast with methylene blue, ask us on a call; the honest answer is that we have not measured it and will not claim it until we have. The live demo on the site is a mammalian sample; a demo on your own slurry is a call away.
The published figures on manual counting variability, and the benchmark behind the accuracy claims, are on the validation page.