Yeast is the fundamental part of fermentation, the desired flavour profile and an efficient and reliable attenuation a brewer is looking for, depends on his work. However, in Argentina and Chile the great majority of brewers are using new dehydrated yeast for every batch and only a few of them are storing and reusing yeast in-house. This situation implies not only the waste of yeast itself, as an important and expensive coproduct of beer making, but also is detrimental in terms of quality, repeatability and differentiation of products. Most brewers use just a few brands and strains of yeasts (mainly S-04, Notthingham, US-05).
In order to consistently manage yeast in breweries the use of a microscope becomes fundamental. It allows to count and evaluate the viability of cells and to determine the optimal pitching rate for every new batch. Moreover, this practice is an excellent starting point for brewers to increase knowledge and experience about the microbiology involved in brewing.
The standard procedure of counting requires an optical microscope and a Neubauer chamber where the yeast sample is quantified. Recent approaches to DIY microscopy in the biohacker movement can be tested and improved to communicate and facilitate this task to brewers.
Brewers use a few very specific species of yeast for their products. The brewer’s genus is Saccharomyces. There are two main species of brewer’s yeast, ale and lager: S. cerevisiae (ale yeast) and S. pastorianus (lager yeast). However, the relatively recent discovery of S. Eubayanus in the Patagonia, from both sides of the Andes, has increased the attention from brewers to yeast in general and specially to its local strains.
The goal of our design is to allow the consistent evaluation of viability and count of yeast cells from a digital image taken with a low-cost DIY microscope.
The materials for the microscope prototype should be easily available.
Integrate the hardware output with already existing informatic tools for manual and automatic yeast counting.
We will develop, test and characterize different low-cost DIY microscope prototypes. We will base our designs in already existing open-source microscope projects (open flexure, flypi, openscope, etc).
We will try different optics, illumination, stage manipulator and camera setups. We will try the standard Neubauer chamber counting procedure and characterize our results with standard USAF images in terms of size of pixels (i.e. nm per pixel), field of view, resolution and any distortion that might be present.
We already started to build and test some prototypes (ie. image 1 and image 2). The url of the git repository is
All documentation to replicate the prototypes and reproduce the counting experiments will be shared in our git repository along with other relevant resources.
At the end of our project we expect to have a low-cost good enough DIY microscope prototype to aid artisanal brewers in counting and evaluating the viability of yeast cells.
These prototypes made of easily available components will benefit local brewers that could replicate them by themselves or during workshops to start reusing and pitching their beers with in-house grown yeast. Hopefully, these tool will provide them with a solid starting point to build knowledge about many other different aspect and practices related to the microbiology of brewing.