OnTap Magazine

Traditionally, rehydration is achieved through one of two processes. Dry yeast can be sprinkled into ten times its volume of sterile water (mineral water, demineralised water, or tap water provided chlorine levels are not too high). Alternatively, it can be added to sterile wort that has been cooled down to the optimal temperature for rehydration. This is recommended to ensure the right bacteriostatic properties as the rehydration phase can leave the yeast cream vulnerable to contaminants. The initial density of the wort has no bearing on the yeast’s viability (no significant differences between 7 and 25 °P). The rehydration environment should be at a temperature of between 10 and 28 °C, ideally within the same range as the fermentation temperature. The mixture is left for 15 minutes. It can be stirred gently but excessive mixing will damage the yeast membrane and reduce its viability. The yeast cream is then transferred to the fermentation vessel containing the wort, at the required temperature for pitching. Direct pitching is a straightforward, safe and sustainable option. Simply open the sachet and pour the correct quantity into the fermentation vessel as it fills. This should be done in a clean environment, either using a sterilising lamp or having disinfected surfaces with alcohol to prevent microbial contamination. Since dry yeast membrane's sterol and oligoelement levels are conducive to budding and growth in the initial stages of fermentation, there is no need to aerate the wort prior to pitching. The quantity used (weight/hl of wort) will have a direct impact on performance. If the pitching rate is too low the process will take a long time to get going, increasing the risk of contamination. Recommended quantities are 50-80 g/hl (4-6 106 cells/ml) in the case of Saccharomyces cerevisiae and 80-120 g/hl (8-12 106 cells/ml) in the case of Saccharomyces pastorianus . If multiple batches are added to the fermentation vessel over a periodof time, we recommend adding the full quantity of ADY as soon as the first batch has cooled. Direct pitching should not be used for refermentation. Standard practice involves hydrating the yeast before adding it to the beer. Adding to a conditioning tank for 15 minutes before bottling ensures even distribution of the yeast. CO2 (g/l) g/hl 0.5 1.5 3 6 ABV (%) 5 2 7 7 14 8 2 7 7 14 12 7 14 14 35 10 REASONS TO CHOOSE SafYeast TM RELIABILITY 1 EASE OF USE 2 NO EXTRA CARE 3 STABILITY 4 QUALITY 5 AVAILABILITY 9 CREATIVITY 8 FRESHNESS 7 CONSISTENCY 6 10 NO CAPITAL AND COST INTENSIVE YEAST MANAGEMENT Preferred partners : SafYeast TM is a utility brand which covers all our Fermentis Active Dry Yeasts. To discover it, scan our QR code