An exclusive interview with a leading brewing company

Transcription

1 2 An exclusive interview with a leading brewing company Jules Wyss, Quality Manager Feldschlösschen Beverages Group (Carlsberg), Switzerland What importance does the Feldschlösschen Beverages Group attach to dissolved oxygen analysis? It has indeed a very high priority. Following the fermentation process it is important that virtually no oxygen whatsoever finds its way into the beer. The limit values for oxygen have been continuously reduced over the last decade or so, and we already installed our first in-line measuring system in Has then the presence of oxygen within the production process a direct influence on product quality? Absolutely. Before fermentation, oxygen is significant for the yeast propagation. Afterwards however, practically no oxygen may be present in the beer as it strongly effects flavor stability. In addition, oxygen influences the chemical-physical equilibrium which is important for the keeping quality, the shelf life of the beer. In which process stages are oxygen measurement regularly taken? In all, we have nine in-line systems fixed installed. These are spread out within the process, namely, two installations in the filter cellar, two at the outlet of the pressure tank, two in the degassing plants, and one each at the wort aeration installation, the filling station for so-called gastrotanks and the filling station for kegs. What are the measurement ranges within the complete process sequence, right through to measurement in the bottle? During wort aeration, we measure about 6 mg/l. Afterwards, the measured values drop sharply to between 20 to 30 ppb, whereby of course the set limit value lies much higher. What in your opinion is the future of oxygen analysis in the brewing

2 Contents An exclusive interview with a leading brewing company Jules Wyss, Quality Manager Feldschlösschen Beverages Group (Carlsberg), Switzerland. Measuring minute amounts of DO in beer! Glass-free ph measurement in breweries The new non-glass InPro 3300: successful use in Asian brewery Certification for conductivity no issue Impressum Publisher Mettler-Toledo GmbH Process Analytics Im Hackacker 15 CH-8902 Urdorf Switzerland Production MarCom CH-8902 Urdorf, Switzerland Technical articles Mettler-Toledo GmbH Prozessanalytik D Gießen, Germany Illustrations Archive MarCom CH-8902 Urdorf, Switzerland and D Gießen, Germany industry generally and at Carlsberg specifically? Our company is consistently extending the use of oxygen analysis. Since being taken over by Carlsberg there have been substantial investments including those specifically directed towards quality management. In conjunction with the renewal of the control systems for fermentation and storage, the wort aeration will be equipped with two additional in-line measuring systems. The future new degassing plant will be fitted with an in-line control measuring point right from the beginning. The same applies to the new can filling station. Further production stages will also be fitted with new measuring points in the near future. I think that generally there is an increasing tendency in the brewing industry for carrying out overall, consistent oxygen analysis. The effect of oxygen on product quality is simply too great for companies to justify any saving on investment in the analytical field. Which method did you use in the past for oxygen measurements? The evolution of oxygen analysis in Rheinfelden began with laboratory measurements. These were inexact and time- consuming. Later, we introduced the first mobile measuring instrument but quite quickly turned strictly to fixed in-line systems. These offer the possibility of obtaining continuous measurement data without having to depend on grab samples. Why then has the mobile method of measurement still remained important alongside that of in-line measurement? Even the best in-line measurement system has to be checked for accuracy from time to time. ISO 9002 indeed prescribes that procedures must be in place to control the function of installed measuring equipment. Measurement with a portable unit still remains our standard reference method for supervision of each and every measurement point. For me, the InTap 4000 from represents the required control equipment. Currently, inspection, measuring and test equipment has taken on greater importance with us, and consequently, mobile systems for oxygen analysis also. Moreover, a portable analyzer in conjunction with a flasher head device will still continue to be used for in-bottle measurements. Subject to technical changes. Mettler-Toledo GmbH 07 / 03 Printed in Switzerland. 2

3 Since when have you been using the InTap 4000? We have been using the InTap 4000 since the beginning of Previous to that, we tested a prototype unit for about 2 months under full actual working conditions. The unit was very convincing all along the line. What are the main advantages of the InTap 4000 in comparison with existing portable analyzers? There is a whole range of differences which distinguish it from existing units. Particularly pleasing is the very low maintenance time requirement and especially rapid membrane replacement which in other systems is extremely time-consuming and complicated. With the InTap 4000 it is a matter of just two minutes. As we employ very few laboratory personnel, such maintenance work has to be carried out without spending too much time. A further bonus is the ease of operation, which allows the unit to be used by a large number of different persons without first having to provide a great amount of technical instruction. An additional central feature of the unit is that its sensor and membrane concept fully accord to that of the in-line systems. This makes a lot of things easier. I also consider the low energy, and therefore low battery consumption to be another cost advantage. It is light to hold, and very easy to clean, and I highly appreciate the accompanying data transfer software. Taken as a whole, the new analyzer is clearly a great step forward from its predecessors. Mr. Wyss, we thank you very much for this interview. 3

4 Always one step ahead: Measuring minute amounts of DO in beer! The new InPro 6900 DO Sensor is a revolutionary design which supports precise measurement of particularly low concentrations of dissolved oxygen. It is sterilizable and is fully compatible with CIP protocols, allowing the sensor to be cleaned in place if required. InPro 6900, sensor to measure low ppb oxygen levels. How does it work? The InPro 6900 is based on a polarographic DO principle discovered by Clark. The Clark sensor consists of a working electrode the cathode, a counter-/reference electrode the anode and a membrane permeable to oxygen, which separates the electrodes from the measuring medium. A constant polarization voltage is applied between the cathode and anode. The oxygen molecules diffuse from the measuring medium through the membrane to the cathode and are reduced there. At the same time, silver is oxidized to silver chloride at the anode. The resulting current from this cathode/anode reaction is proportional to the partial pressure of oxygen. The attached transmitter finally converts the oxygen partial pressure into an oxygen concentration. Small but significant differences The InPro6900 sensor is based on the Clark oxygen electrode described above. However, it also contains an additional cathode ring that is connected to a separate polarization voltage. This additional cathode, also called the protection ring, consumes oxygen which may already be dissolved in the electrolyte. Combined with a patented electrolyte, this technology supports for exceptional accuracy, especially in media low in oxygen. Functional principle DO Sensor R I Polarization voltage Anode Isolator Cathode Electrolyte Temperature Sensor 4 Measuring medium DO DO DO Membrane

5 Glass-free ph measurement in breweries ph is one of the most important parameters for process control in brewing, whether during preparation of the mash, in the wort, during fermentation or when checking the final product. Until now, monitoring ph was mostly done offline in the laboratory or on a mobile basis through grab-sample analysis/spot checks, which are timeconsuming, prone to error and hinder process automation. The non-glass ISFET technology found in Ingold s newest ph sensor completely eliminates one of the oldest concerns about broken glass while monitoring ph in beer. InPro 3300: glass-free ph electrode. Optimal sensor design for reliable measurement values. Innovative, safe, hygienic The new ph electrode InPro3300 from is based on innovative ISFET (Ion Selective Field Effect Transistor) technology. The ISFET sensor technology is completely glass-free, which opens many new potential areas of application. All parts which come into contact with process medium are made of FDA-approved materials (PEEK, EPDM), and the design is certified by EHEDG, assuring optimal cleanability of the sensor. Pressure resistance has also been tested and certified according to the pressure equipment directive PED 97/23/EEC, Art.3, Para.3. Complete systems ISFET sensors require special electronics. The new transmitter ph 2100 e operates as a dual function transmitter, fully compatible with ISFET technology, or classic, glass ph electrodes. For optimum process connection, the new retractable housing InTrac798 is also available. ph set value optimal ph value Light (full) beer approx.4.5 Fermentation 5.6 to 5.8 Outstanding features Due to the very small sensor surface area of ISFET electrodes, response is particularly rapid. Measurement accuracy in alkaline solutions is very high, and unlike glass electrodes, alkaline error is virtually non-existent. The high-performance reference system of the InPro3300 guarantees excellent stability during sterilization and throughout innumerable CIP cycles. The beveled sensor tip (inclined at 45 ) prevents adherence of air bubbles, thereby resulting in higher stability of the measurement signal. The ph 2100 e, state-of-the-art transmitter technology. 5

6 Asian brewery optimizes yeast yield with non-glass ph electrode The new non-glass InPro 3300: successful use Yeast is one of the most important substances used in the beer brewing process, acting as a catalyst in the fermentation process. To control and optimize yeast output means to directly influence the costs. The research department of a large beer company in Asia was very pleased with the results when they used the new non-glass ISFET from METTLER TOLEDO to target higher performance in the fermentation process. A major Asian beverage company with more than 2000 employees recently decided to purchase a non-glass ph system after a two months evaluation phase. Quality is a key factor for them as well as optimization of the beer brewing process. Non-glass ph measurement to save money One section of their research department focuses its activities on studies to optimize the output of yeast cultures. In this respect they were looking at non-glass sensors provided by different suppliers. The tested ph system was made up of the electrode type InPro3300, the CIP static housing InFit 761, a cable with VarioPin connector, and the Advanced Line transmitter ph 2100 e. circulation tube with pump which continuously circulated the solution. Besides the ph sensor, three oxygen sensors were installed in the system to ensure optimal control. Temperature conditions were below ambient at atmospheric pressure and aeration of the process was carried out continuously through an external tube. Brewery, clarifying vessel. For their laboratory set-up, they used a medium scale 500 liter tank and one closed Installation of ISFET ph sensor. 6

7 in Asian brewery Once per week, a batch was set up containing a yeast culture, glucose and water. At the beginning there was a ph of approximately 4.5, dropping non-linear to ph 3 after three days, thereby indicating the end of the process. The chief engineer of R&D stated: For a long time we have been looking for a non-glass sensor to measure ph, but we just did not succeed in finding the right solution but the results and the hygienic design of the InPro3300 have convinced us. The non-glass InPro3300 reduces the risk of glass breakage The chief engineer of R&D is convinced that through his studies he can optimize the brewing process in several production plants. If we optimize the yield this is real cash for us and with the new non-glass sensor, we additionally reduce a major safety risk. No fear of broken glass in the medium The new, unbreakable non-glass In- Pro 3300 ph electrode supports on-line ph control as a key element in meeting customer s expectations. Proof of outstanding and durable quality Tested in accordance with the guidelines of the EHEDG (European Hygienic Equipment Design Group) and conformance with 3-A sanitary standards provides assurance that the equipment complies with the criteria for hygienic design. Compliance with FDA (Food and Drug Administration): only white-listed material is used to guarantee meeting the requirements of the food and pharmaceutical industries. Advantages and benefits for the customer Enhanced process safety by eliminating the risk of broken glass in the process Cost effectiveness through being able to avoid time-consuming grab-sample analysis Process safety through hygienic design (EHEDG, 3-A, FDA) The sensor has been developed and manufactured in accordance with recommendations for extremely high-level hygiene applications. These attributes in combination with the unbreakable design feature of the non glass InPro3300 sensor are representative for METTLER TOLEDO s ability to continuously bring new and technological innovative products to the market. ph ISFET sensor InPro3300. Technical specifications for InPro3300 ph 0-14 Temperature 0-80 C, F for measurement C, F for sterilization Pressure 0-6 bar/0-87 psi Shape 45 angle prevents air bubble problems Shaft 12 mm, PEEK Connector VarioPin (VP) IP68 Temp. sensor yes (Pt 1000) Hygienic design yes (EHEDG, 3-A, FDA) 7

8 Certificates for conductivity no issue CIP-suitable conductivity sensor InPro7108. All conductivity sensors are equipped with a VarioPin (VP)connector (IP68). As a result, wet or corroded plug-in connections are now a thing of the past. All new sensors are supplied with a declaration of conformity 2.1, 3.1B testimonial, and a certificate listing cell constants. The cell constant is extraordinarily accurate due to the use of ultrapure water as the method of reference. Do you need a sensor able to meet the demands of all common Cleaning-In- Place (CIP) and Sterilization-In-Place (SIP) methods? In that case, the InPro 7108 made of PEEK (grade 450, level 6) is precisely the right choice. Do you only want to measure in the ms range or do you need a specific connection? Not a problem, the appropriate choice is available from. Mettler-Toledo GmbH Process Analytics Im Hackacker 15 CH-8902 Urdorf Switzerland INGOLD Leading Process Analytics 8