Using Fermentation Profiles to Optimize Yeast Cropping

Optimize Yeast Harvesting

Harvesting yeast can be a significant cost saver for breweries. Today, most brewers are reusing yeast a set number of times, e.g. 5 times, before replacing it with a new culture. Comparing the fermentation profiles between batches, and paying attention to the duration of the lag-phase and the rate of fermentation, one can use these two parameters as a direct and quantifiable measure on how well the yeast is performing.  

Top Cropping at the Peak of Fermentation

Top cropping is the method of harvesting yeast from the surface of the fermenter, typical with ale strains. Compared to bottom cropping, this technique extracts yeast with superior vitality and viability, but the process is more challenging because of the closed nature of most conical fermenters today. Top cropping should happen when the rate of fermentation is at its peak.

Timing of Bottom Cropping is Crucial

Yeast collection must start as soon as possible after the end of fermentation, because yeast cells will start to break down and deteriorate at this point. Use fermentation profiles to determine the precise end of fermentation and pinpoint when to collect the yeast. Large conical fermenters are challenging for the cells to handle, due to the tight packing of yeast in the cone. The typical point of harvest is 24-48 hours after a cold crash, and further delays will significantly reduce the yeast viability.

The fermentation profile seen here is generated PLAATO Pro. If you are interested in getting fermentation profiles for your brews, simply contact us on the PLAATO Pro page.