Coldblock - challenges and solutions

Professional equipment for the fermentation process

A consistent, reliable and effective fermentation process relies on equipment that guarantees high-quality yeast management, hygienic design and accurate control of the process variables.

Our cold block process solutions help overcome common issues to unlock the full potential of your commercial brewery process line.

Yeast management


  • Need for yeast propagation, storage and recovery


  • Healthy yeast alternative with high viability and vitality
  • Correct pitching
  • High flexibility for propagating, storing and pitching different yeast strains


  • Ensuring the supply of uninfected, freshly propagated, high-quality yeast



  • Yeast with high viability and vitality
  • Correct pitching
  • Homogenous yeast slurry
  • More flexibility for propagating, storing and pitching different yeast strains

Fermentation and maturation


  • Foaming issues when wanting to improve fermenter utilization
  • Repeatability of fermentation process



  • Less foaming allows increased use of overall fermenter capacity
  • Homogeneous distribution to prevent premature settling of yeast
  • Uniform temperature and CO2 levels
  • Consistent and shorter fermentation time


  • Long overall process time in fermenters


  • Energy efficient crash cooling
  • Desired temperature reached while transferring green beer


  • Subpar hygiene in fermentation systems and interconnecting transfer lines


  • Product contact areas effectively and reliably cleaned
  • Optimization of uptimes


  • Long sedimentation process time
  • Beer loss


  • Reduced maturation time (no need to wait for yeast to settle)
  • Reduced beer losses


  • Excess yeast


  • Recover up to 88% of your beer from yeast bottom

Dry hopping


  • Low yield 
  • Repeatability
  • Extended process time when dry hopping on a large scale


  • Maximized use of hop
  • Accelerated dry hopping process
  • Improved downstream clarification
  • Improved hop removal

Beer sampling


  • Inconsistent, unhygienic and time-consuming product sampling


  • Increased sampling quality and frequency
  • Reduced time spent taking samples



  • Long and costly cycles
  • High energy and chemical usage during cleaning sequences


  • Customized, verifiable system
  • 30% saving in cleaning time and chemical consumption
  • Reduced energy for hot (up to 70%) and cold CIP (up to 50%)
  • Optimal recovery and re-use of cleaning fluids
  • Automated operation

Coldblock overall design


  • Safe operation of large vessels (yeast management, fermentation, bright beer tanks)



  • Integrated safety systems
  • Consistent, repeatable and hygienic operation


  • Suboptimal cold block design



  • Avoidance of contamination
  • Optimization of pumps and lines
  • Optimization of complete process and utilities
  • Increased level of process flexibility

Q&As about Cold block


Q: Do you have any experience in designing and building fully automated (>1M HL) cold blocks that are essentially unmanned?

A: Yes, and we believe this is going to be the future.

Q: For dry hopping on the top plate, how do you prevent micro-contamination during hopping?

A: We arrange Cleaning-in-Place for the complete system before and after hopping.

Q: Are membrane pumps really better for yeast harvesting compared to lobe pumps? Or did you choose membrane pumps for Yards due to thick yeast?

A: We chose membrane pumps due to thick yeast and the capability of a membrane air-driven pump to pull and create suction.

Q: How we can merge the yeast propagator with the yeast storage tank, given that certain changes are required such as agitation of the storage yeast and the challenge that during propagation there may be the risk of contamination in the agitator?

A: Any yeast storage tank can be used as a yeast propagator. It requires some adaptations, however. Alfa Laval Scandi Brew agitators are fully cleanable and SIPable.

Q: For the yeast management plant, I see from your design and installations that sterile air injection occurs via the agitation shaft. What is the advantage of doing so compared to traditional injection at the base of the tank?

A: At Alfa Laval, injection through the hollow shaft is the traditional and preferred option. Distributing air just below the agitator blades helps to distribute air efficiently in the tank.

Q: Regarding the yeast pump, I understand that one pump can be moved close to the tank being harvested... A fixed pump which sometimes presents the challenge of long suction lines, which leads to harvesting problems like flow stability. How does the pump behave in this situation, when using one fixed pump for a complete tank block?

A: It really depends on equipment layout, pump type and yeast type. Each case should be evaluated individually to select the best option.

Q: Do you offer retrofit/upgrade services for breweries that require upgrade of the existing cold block if the customer provides calculations that demonstrate a clear business case in terms of the annual volume required?

A: Yes, we do offer retrofit and upgrades.

Q: Do you have energy-efficient solutions for cold blocks in de-alcoholization plants?

A: Yes, Dealcoholization Module and Lowal Dealcoholizer.

Q: Did using a single diaphragm pump for all tanks via a flow plate lead to delay? Could using multiple pumps help increase production?

A: Using a single diaphragm pump did not lead to delay. Production capacity is not influenced by the efficient harvest. It was relevant for production efficiency and yeast management optimization.

Q: How do you customize your construction sets of P&IDs to meet each customer's needs and what are some typical challenges you face with customers knowing you have a set of P&IDs you pull from? 

A: We apply our process and engineering knowledge to customize sets based on the individual customer's needs. Explaining the benefits of hygienic design, layout and ease of operation is a challenge.

Q: About the use of u-bend pipes for future expansion, are there pressure losses in these pipes that should be taken into consideration?

A:There is a pressure loss in each bend, whether or not it is installed in the expansion loop. Alfa Laval uses special software to calculate both pressure losses and expansion loops.

Q: How is valve matrix drip tray clean during months or years of use? 

A: Alfa Laval mixproof valves are spillage free. When the valve opens or closes, there is no product spillage during valve operation, and none through the leakage chamber either. Consequently, there is no product (yeast, beer, etc.) left in the drip tray during standard operation. If, for some reason, the valve leaks and product is found in the drip tray, it can be manually flushed after routine valve maintenance. Optional cleaning spray nozzles can be installed in the drip tray and activated on a timely basis. 

Q: What, in your opinion, would be the best transition from a cellar with pipe bend panels to a semi-automated cellar, considering the various steps that must be implemented? 

A: We would recommend starting with product routing to maintain manual Cleaning-in-Place (CIP) and manual gas routing. If the cellar is split into blocks, we recommend initially converting one block to semi-automated operation and then converting subsequent blocks until all blocks have been converted. 

Q: You mentioned that tanks undergo cold Cleaning-in-Place. Is this due to caustic or acid cleaning? If due to the presence of caustic, how do you vent the vessel before CIP? 

A: Tanks undergo cold Cleaning-in-Place for both caustic and acid cleaning. For venting the vessel, we use blowers at the bottom to evacuate CO2 from the tank and replace volume in the cylindrical conical tanks (CCT) with the sterile air. 

Q: Do you typically use check valves to protect pipelines from contamination, for instance those pipelines for deaerated water? 

A: No, we try to avoid using check valves in the brewery process installation, especially for transporting product, for hygienic reasons. We always design routes for deaerated water to ensure that they are fully cleanable with hot CIP and we focus on correct functional description in order to prevent product from going back into deaerated water lines. 

Q: When setting up a new fermentation cellar, how much excess space do you recommend for future expansion? 50% of the capacity or more? 

A: It depends on expansion needs and business growth plans. That said, we would recommend a minimum designing with a minimum excess space of 50 to 100% of the existing tank farm.