WHITE PAPER. How to reduce energy during the wort boiling stage of brewing with Steam Infusion. Multi-Award Winning Technology

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1 WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion. Multi-Award Winning Technology

2 Reducing Energy Consumption in Wort Boiling Wort boiling is a key stage in the brewing process and typically in a traditional setup, it accounts for up to 60% of the total energy demand of the brewery. Many complex reactions occur during the wort boiling that are critical to the brewing process. This includes stopping enzyme activity, sterilisation, the conversion of SMM (S-methyl methionine) to DMS (dimethyl sulphide) and the isomerisation of hop alpha acids which gives the beer its bitter taste. The vigorous boiling process also ensures that the bubble stability is sufficient for optimised trub formation and volatile stripping. This traditional method of boiling is very inefficient and requires high amounts of energy consumption for the boiling process to be effective. Using OAL s Steam Infusion heating system generates the required conditions whilst consuming less energy than the traditional method. The Steam Infusion Vaction Pump is a patented processing device that uses steam as the motive force to heat, mix and pump liquids simultaneously. University of Lincoln research and brewing reference sites demonstrate the technology s unique ability to transfer energy more efficiently than traditional processes. The following white paper explains why brewers use Steam Infusion rather than traditional external wort boilers (EWB) to achieve: Up to 40% savings in energy. Zero burn on for easy cleaning and maintenance. Improved consistency. Up to 50% reduced cooking time. About the Author Ian draws on over thirty years of experience working for companies such as P&G and APV within R&D, design, and project management together with leading product, service and engineering activities. Ian facilitates Performance Optimisation projects within the food industry in a global position utilising Six Sigma and Lean methodologies. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 2

3 Steam Infusion Success at Shepherd Neame Shepherd Neame, Britain s oldest brewer, has reduced energy consumption by 40% by switching from an external wort boiler (EWB) to a Steam Infusion Vaction Pump system. Energy Savings Shepherd Neame is a traditional brewery with two coppers; one for ales and one for lagers. The EWB s on both coppers needed replacing and following trials, a three Vaction Pump Steam Infusion array was purchased for the ale copper. After a successful installation and commissioning period, the boil time was reduced from 60 to 30 minutes without any noticeable impact on the taste of the wort (or beer). The combination of lower steam usage during the boil phase and this reduction in boil length gave an average saving of 47% of the combined raise to boil and boil energy. Typical Raise to Boil Energy (MJ) Typical Boil Energy (MJ) Typical Total Energy (MJ) Calandria 4,754 4,486 9,240 Steam Infusion Wort Heater 3,795 1,103 4,898 Typical Savings 20.2% 75.4% 47.0% A traditional wort heater returns condensate to the boiler as hot water. With the Steam Infusion Wort Heater, there is no condensate return to the boiler so these energy savings need to be reduced slightly to include this. Calculations including this loss of condensate return, suggest an overall reduction in energy of 40%. As a result of the first pump s success, Shepherd Neame ordered a second. For this 300 hl copper, a four Vaction Pump array was installed which generated a further increase in energy savings. Again, the boil time was reduced from 60 to 30 minutes and a 57% reduction in steam usage was achieved. Once the lack of condensate return was included in the calculations, this figure was slightly reduced to give a 50% energy saving. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 3

4 Case Study Shepherd Neame Continued: No Burn Leads to an Extra Brew a Week The brewery was also able to increase production as a result of switching. Before the installation of the Steam Infusion Wort Heaters, the existing EWB s were cleaned twice a week using a caustic CIP solution. Post-installation and not having the challenge of burn on during cleaning, they reduced this to just once a week (along with other brewhouse equipment) and as Shepherd Neame was limited by copper volume, not fermentation volume, they were able to run an extra brew, per copper, per week. The quality of their beer between brews also increased because there was now no accumulation of burnt material on surfaces. Improved Flavour Stability: A study carried out at VLB (Berlin) showed the improved keeping qualities of Steam Infusion brewed beer; these scientists concluded All the analyses (ESR EAP detection, BAX determination, determination of staling carbohydrates and ageing taste tests) gave the same result the Steam Infusion brew performed significantly better in terms of flavour stability than the control brew. VLB (Berlin) Steam Infusion Wort Heater. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 4

5 What is a Steam Infusion Wort Heater? The Steam Infusion Wort Heater fits onto a recirculation route from the copper and comprises of a Vaction Pump, the number of which will vary dependent on throughput. The Vaction Pump is a fluid processing system designed to provide mixing, pumping, heating and agitation of a slurry/fluid through rapid expansion and condensation of steam passing through the device. The simple design makes it easy to incorporate into a new set-up or fit it into an existing brewhouse replacing a traditional wort boiler or adding it to the copper using an external recirculation loop. The system can then be adapted for different copper sizes by varying the number of Vaction Pumps together with the size of the expansion column. It is the expansion column on the outlet of the Steam Infusion array that allows for extended two-phase flow; a key requirement for efficient volatile stripping. The heater is placed close to the copper and the wort re-circulated through the array returning back into the copper piping via a spreader plate. Copper with Steam Infusion Recirculation Route. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 5

6 How the Vaction Pump works? In a brewery set-up, the Vaction Pump is located in the recirculation line. 1. Wort floods the Vaction Pump in the recirculation loop and culinary or clean steam is introduced into the pump. It has no moving parts and uniquely uses steam to simultaneously heat, mix and pump the product. 2. Profiling within the steam chamber accelerates the velocity of the steam to 1,000m/s, above the speed of sound. The steam passes into the mixing chamber through an annular nozzle disrupting the wort flow to form small droplets, referred to as the vapour phase. The momentum transfers from the steam to the product and creates a partial vacuum of -0.7 Bar within the pump. 3. As the steam condenses into the fluid droplets, the pressure rises referred to as the condensation shock-wave which generates a pumping effect. 4. The small droplets within the low-pressure vapour phase offer a significantly increased product surface area for the steam to condensate into typically resulting in a near instantaneous temperature gradient of 12 C (depending on the configured operating conditions). 5. This combined with the design of the expansion tube which promotes extended two-phase flow, enhances the volatile extraction and stripping performance of the pump. 6. This provides for no hot surface contact or hot spots preserving the quality of the wort and minimising Maillard Reaction, burn on and caramelisation of certain sugars. In return, this speeds up cleaning post-production and a reduces CIP chemical use and waste disposal. One consequence of using Steam Infusion to heat the wort is reduced evaporation. Traditional wort boiling uses large amounts of energy and evaporates up to 9% of the wort volume. As the Steam Infusion Wort Heater uses significantly less energy, evaporation is reduced. Experience in production scale installations of the Steam Infusion Wort Heater suggests that no net evaporation or dilution occurs during wort boiling; therefore, the boiled wort is slightly more dilute than that from a traditional process. The simplest way to compensate for this lack of evaporation is to slightly reduce the quantity of sparge water thereby increasing the initial gravity of the wort. Vaction Pump Cutaway. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 6

7 The Main Benefits of a Steam Infusion Wort Heater: Steam Savings Studies with Campden BRI together with commercial installations have shown significant energy saving during the wort heat up and boiling cycle compared with traditional heating methods. Zero Burn On Conventional methods of wort heating rely on contact with a hot surface resulting in wort burn. With the Steam Infusion Wort Heater there is zero burn on reducing cleaning times and cost. Improved Consistency In a traditional calandria the burn on increases gradually between cleaning cycles resulting in a detrimental impact on beer quality. Accelerated Cycle Times In one case, boil time was reduced from 60 to 30 minutes with no impact on beer quality. Furthermore, being able to heat the wort during the filling of the copper has resulted in a 20-minute reduction in cycle time. Readily Retrofitted The system can be easily fitted into existing set-ups or incorporated into the design of new brewhouses to replace an existing external wort boiler (EWB) or be added to a copper with an internal calandria by way of an external recirculation loop. Energy Saving The profile of a representative run using the Steam Infusion Wort Heater and a corresponding EWB run found that to maintain the desired exit temperature, the EWB used a steam flow rate of 140 Kg/hr whereas the Steam Infusion Wort Heater used only 90 Kg/ hr. Once the lack of condensate return is factored in, this equates to an energy saving of 23%. Using an EWB with a steam usage of 140 Kg/hr gives an evaporation of approximately only 3%/hr. If evaporation was increased, the savings incurred by using a Steam Infusion Wort Heater would be significantly higher. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 7

8 What is the Impact on Beer Quality? Analysis and comparison of multiple samples taken during matched 90 minute boils (the standard boil time for this client), using Steam Infusion and a conventional EWB found that the different methods of heating did not introduce any variation in the measured parameters. S-methyl Conversion to Dimethyl Sulphide S-methyl methionine (SMM) degradation was predictable and independent of the heating method. This was the expected result as both methods of heating maintained the copper at boiling and the rate of this reaction is determined by temperature and time. By the end of 90 minutes boiling, the SMM levels were very low. It is important to decrease the SMM concentration to a low level so that there is no potential degradation to DMS later in the process, particularly during pasteurisation. The dimethyl sulphide (DMS) stripping appeared very efficient for both heating methods. The DMS concentration at any point in the wort boiling time course is a combination of its formation by SMM degradation and its removal by volatile stripping. This is affected by the number (and size) of bubbles generated by the chosen heating method and the results show no difference between the Steam Infusion Wort Heater and EWB heating methods, both resulting in very low levels by the end of the boil. Isomerisation The rate of hop alpha acid isomerisation was also the same for the Steam Infusion and EWB wort heating comparison. Again, this is an expected result as both methods of heating maintained the copper at boiling and the rate of this reaction is determined by temperature and time. Another set of analytical measurements showed the resulting increase in bitterness. This also increased at a very similar rate in both the Steam Infusion and EWB data sets. Trub Formation The rates of trub formation did show different profiles. It appeared that the rate of trub formation by Steam Infusion wort heating was higher than that of the EWB. However, after minutes of boiling using the Steam Infusion Wort Heater, the trub volume peaked and began to drop. Nitrogen analyses of the pitching wort showed no difference between Steam Infusion and EWB processed wort, suggesting that with both systems, the trub had been effectively removed in the whirlpool. The analytical results showed no difference in quality between the wort treated using the Steam Infusion and traditional EWB heating systems. The Steam Infusion Wort Heater and EWB both gave the desired changes during the course of wort boiling, but the Steam Infusion system used significantly less energy. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 8

9 How Much Money will I Save? To quantify the financial benefits that can be achieved through the installation of the Steam Infusion Wort Heater, we ve developed a tool to calculate the potential savings. The model requires simple inputs such as copper volume, evaporation and current steam usage to report back: A summary of the total achievable savings, including steam, CIP chemicals, effluent discharge, etc. Key financials, such as Discounted Cash Flow, Return on Investment and Payback. Potential cash flow over the analysis period. The Steam Infusion Wort Heater introduces a paradigm shift in energy savings within the brewing industry without impact on beer quality. Professor Richard Sharpe of Campden BRI OAL WORT HEATER POTENCIAL SAVINGS CALCULATOR Basis of Savings Calculations Calculated Annual Volume 585,000 hl Brew Size 450 hl Number of Coppers 1 Number of Brews per Week per Copper 25 Evaporation 8.0% Wort Inlet Temperature 96 C Current Steam Use per Copper Brew Boiler Eficiency 83% Boiler Header Steam Pressure 8.0 bar gauge Steam Pressure at EWB 5.0 bar gauge Cost of Water 1.10 /m3 Cost of Boiler Fuel per kwh Cost of Electricity (Vapour Re-compressor) per kwh Mass of CO2 per kwh of Boiler Fuel tonne CO2/kWh Calculated System Parameteres Calculated No. of Brews per year 1,300 Calculated Brews per Copper per Year 1,300 Theoretical Steam Use - 100% Efficient at 5barg & 8% Evap. 3,205 kg Actual External Calandria System Efficiency Actual External Calandria Energy Use / Hectolitre MJ/hl kwh/hl Actual External Steam Cost per Point of Use per kg Actual Mechanical Vapour Re-compressor Energy Use per Year N/A Theoretical Calandria Energy Use / Hectolitre MJ / hl 7.73 kwh/hl Theoretical Calandria Steam Cost per of Use per kg Theoretical OAL Steam Use to Reactor Array 1,261 kg Theoretical OAL Energy Use / Hectolitre (inc. Condensate Loss) 8.51 MJ / hl 2.36 kwh/hl Assumed Additional Energy Load for Wort Recirculation Pump N/A Potential OAL Savings Standard External Calandria Operating Costs /hl /Brew /Copper/Year /Year Cost of Steam , ,885 CIP - Cost of Caustic CIP - Cost of Rinse Water and Effluent Discharge CIP - Cost to Heat CIP Solution Calandria Pressure Test (Annual Cost) Total Operating Costs , ,169 Steam Infusion Wort Heater /hl /Brew /Copper/Year /Year Operating Costs ,889 59,889 Cost of Condensate Replacement to Boiler ,345 11,345 Cost of External Wort Recirculation Pump CIP - Cost of Caustic CIP - Cost of Rinse Water and Effluent Discharge CIP - Cost to Heat CIP CIP Solution Total Operating Costs ,047 73,047 Total Cost Savings /hl /Brew /Copper/Year /Year , ,123 Total CO2 Savings T/hl T/Brew T/Copper/Year T/Year WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 9

10 Frequently Asked Questions: Will Direct Steam Heating Affect the Beer? No. Direct steam heating is a common method of heating many food products and many food companies use Steam Infusion in their cooking processes. Obviously, the condensate from steam is pure water and the only difference from mains water is a decrease in the ionic content, otherwise known as the water hardness. A comparison of mains water and steam condensate is shown here. Analysis Water Supply Condensate General ph Total Organic Carbon Hardness 345 < 0.05 Conductivity Metals Copper Magnesium 8.58 < 0.19 Calcium 124 < 0.68 Iron < < Lead < < Potassium 9.37 < Sodium 47.6 < The potential for carryover of boiler chemicals is not an issue given proper boiler maintenance and testing. A five-micron hygienic filter in the steam supply will prevent any particulate carryover and FDA approved boiler chemicals are also readily available. The easiest test for condensate purity is to taste the condensate on a regular basis. At Shepherd Neame, this happens every day before the first brew is started. A comprehensive on-line analytical condensate quality protection system can be provided as an option to the Steam Infusion Wort Heater package. What are the Consequences of Reduced Evaporation? Experience with the Steam Infusion Wort Heater at production scale suggests there is no net evaporation or dilution during the wort heating and boiling steps. At Shepherd Neame, the gravity at the end of wort boiling is the same as at the start. This is slightly more dilute than using a traditional EWB or calandria. To compensate for this the starting gravity is increased to the desired level by using slightly less sparge water. If this causes a significant loss of extract then weak wort recycling could be considered. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 10

11 What Next? If you d like to know more about how Steam Infusion can help you save in your brewery, please get in touch to arrange a consultation or a visit to our test centre at the University of Lincoln s National Centre of National Centre for Food Manufacturing, Holbeach. Speak to an expert by calling: Or by ing: deborah.leslie@oalgroup.com Or visiting: A1 Parkway, Orton Southgate, Peterborough, PE2 6YN About OAL: OAL is a family business based in Peterborough UK with a 25-year history of supplying turnkey material handling and processing projects to blue chip UK food manufacturers. Food manufacturers trust OAL to deliver liquid and dry material processing projects up to a value of 5 million where proven experience, design excellence, automation, quality and outstanding support are valued. Customers have guided us with distinct requirements for each sector allowing each team to work as a focused, fast-moving group dedicated to their specific market. The OAL tradition of trust, fairness and investment in our people bonds our teams. We strive to keep our customers ahead and future proofed by leading multiple R&D projects currently valued at 4.5 million aimed at developing tomorrow s tried and trusted. WHITE PAPER How to reduce energy during the wort boiling stage of brewing with Steam Infusion Page 11

12 APRIL Robotics is committed to increasing the efficiency of food factories by enabling the redeployment of people performing repetitive tasks with robotics. Our team are world leaders in using proven robotic technologies to provide next generation food manufacturing preparation and process systems. APRIL Cooking Cell Robotic ingredient handling and processing cell for the automated production of soups, sauces and ready meals. Patents pending. APRIL Material Handling Fully automated material handling with robotics for major, minor and micro ingredient additions. Patents pending. APRIL Weighing Station Automated weighing and management of micro dry ingredients. Patents pending Future Developments With 4.5 million funding from Innovate UK, the UK governments Innovation agency and private finance we re removing all manual operations from food processing. OAL Connected provides market-leading label and date code verifcation systems installed on over 1,100 packing lines, ensuring full compliance with retailer s codes of practice. Once protected, food manufacturers can achieve fast payback using the OAL Connected modules to add OEE productivity measurement, connectivity to line equipment and paperless traceabilty. APRIL Eye Stop human error on your packaging line by reading back and verifying date codes with APRIL Eye, an artificial intelligence machine vision solution. OAL have a 25 year history of supplying turnkey material and processing projects to blue chip UK food manufacturers. Food manufacturers trust OAL to deliver liquid and dry material processing projects up to a value of 5 million where proven experience, design excellence, automation, quality and outstanding support are valued. Turbocharge your cooking process with Steam Infusion heating and mixing, scientifically proven to help food manufacturers overcome slow cooking times, burn-on contamination and over-processing. Learn how you can cook 500kg of fresh sauce in just five minutes on our stand and join the fastest growing cooking revolution in food processing. Would you like to know more? Contact OAL at: sales@oalgroup.com oalgroup.com