Lesson 5 - Wort Cooling and Oxygenation Technology and Process Control SAQ Flashcards
(11 cards)
What is the main pitfall of using a coolship for wort cooling?
Large footprint and susceptibility to microbiological contamination and oxidation
Coolships are large and shallow vessels used to sediment trub and rapidly cool wort, but they expose the wort to potential contamination.
What three key improvements do modern wort cooling systems offer over coolships?
- Separate refrigeration systems for efficient cooling
- Closed systems that are hygienic and cleanable
- Rapid cooling to maintain productive cycle times
These improvements address the limitations of coolships and enhance the brewing process.
What are the main advantages of plate heat exchangers (PHE) for cooling wort?
- High efficiency due to conductive, thin plates
- Compact size and versatility
- Ease of maintenance and inspectability
- Low cost of maintenance and replacement
- Cleanability using reverse flow
PHEs are preferred for their effectiveness in cooling wort quickly and efficiently.
What similarities do shell and tube heat exchangers share with plate heat exchangers?
- Can use counter current flow
- Can use multiple cooling mediums
- Fully cleanable with reverse current flow
Both types of heat exchangers are designed to maximize heat transfer and facilitate cleaning.
What are the differences between shell and tube heat exchangers and plate heat exchangers?
- PHEs use thin, embossed plates
- PHEs are more compact and flexible
- PHEs are quicker and easier to maintain
- PHEs are easier to inspect
These differences make PHEs a more efficient choice for wort cooling.
What are the typical wort collection temperatures for ales and lagers?
- Ale wort collection: 15-22°C
- Lager wort collection: 6-12°C
Ales are generally pitched at higher temperatures than lagers, affecting cooling requirements.
How does high gravity brewing affect wort aeration requirements?
Higher gravity requires more oxygen due to increased pitching rates and decreased solubility of oxygen
As gravity increases, the need for oxygen in the wort also increases to support yeast health.
What are the six focus areas for improving wort cooling?
- Control the volume of wort collected
- Control the gravity of wort collected
- Cool wort to required yeast pitching temperature
- Oxygenate wort to specific requirements
- Maintain cycle times
- Maintain hygiene
These focus areas are critical for ensuring efficient and effective wort cooling.
What is the impact of quick cooling on wort quality?
Prevents further chemical reactions and assures hygiene standards
Quick cooling helps to set the wort profile and maintain the desired quality of the beer.
What strategies can be employed to reduce the duration of wort cooling?
- Increase flow rate through the wort cooler
- Add more plates to the PHE
- Lower cooling water temperature with additional refrigeration
- Add an additional cooling stage to the PHE
- Adjust cooling temperatures for different beer styles
These strategies help to meet new cycle times and productivity requirements.
True or False: Plate heat exchangers are easier to maintain than shell and tube heat exchangers.
True
PHEs are designed for quick disassembly and maintenance due to their construction.
