Lesson 6 - Design of Fermentation Vessels
This unit began with the principles that underpin fermentation. This lesson now explores how these are put into practice. It covers how fermentation vessels must be designed to suit the behaviour of the yeast strain being used, as well as the nature, scale, and sophistication of the processes available.
Point of Reflection – Reconvene:
Welcome back. So what were your thoughts?
The most important factor would be the quantity of beer. We need to know the required annual volume and average fermentation cycle time (including time to fill, empty, and clean).
We first choose a capacity that the brewhouse could supply within reasonable time limits. We could then calculate how many fermentations this would require per year and use this to decide how many vessels we would need to meet the demand.
Once this basic information has been established, additional factors that would need to be taken into account include:
● How does demand vary throughout the season?
● How many hours per day and week can we brew?
● How much time do we need for planned (or unplanned) maintenance?
● How many different beer qualities do we need to brew and at what volume and frequency?
● How does the vessel size fit in with the rest of the brewery?
- Brewhouse batch size and number of brews per day
- Capability of conditioning and filtration
- Packaging capacity
We would also need to factor in any inconsistency in cycle time to make sure we always had a clean vessel ready.
Depending on the portfolio of beers we need to make, we might decide that a mixture of vessels of differing capacities is needed, but then the more vessels we have, the more unit operations we need to carry out, and so costs will increase.
We can see that making such decisions is not as straightforward as it might first appear.