Laboratory instrument for accurate water activity (aw) measurement For assurance of : Quality Product safety Microbiological stability „All life needs water!“ Air and water There is no life without water! the important elements on earth for any life „Water means life! “ Thanks to water, life has developed and new life continues to develop. „Life needs water“. Water is the „elixir of life“ for animals, humans and plants. But bacteria, fungi and viruses also need water to live. Water is stored in every product. Either in the form of a chemical compound with other molecules or as free water, which is stored between the compounds. What is the optimum amount of both types of water now? The amount of bound water is depending on the chemical reactivity of the substances used. Free water can be affected by production processes as well as via storage and packing. Alongside the usage of water, too much free water can particularly damage the product. Microorganisms such as fungi or bacteria can optimally grow and thrive on this surface. Their metabolic products are deposited on the product and spoil the quality. Too high water activity means limited durability. Water activity values, which are too low can spoil the taste or appearance. Only an extremely accurate and safe quality measurement of water activity („free water components“) guarantees quality products! Meaning of „water activity“ (a ) w Water (H2O) is an important basic element in foods as well as in many 0...100% RH corresponds 0.00...1.00 aw pharmaceutical and cosmetic materials and products. For a long time the Free water in products is jointly responsible industry has known how important it is to check free water. The water activity for the growth of undesirable organisms such (aw) measurement forms the basis of this and provides important information as bacteria or fungi, which produce toxins or about the quality of a product. Finally it provides information regarding the other harmful substances. But also chemical/ possibility of microbiological growth on the surface and then conclusions can biochemical reactions (e.g. the Maillard be made about the stability and durability of a sample. reaction) increasingly take place and possibly change the product’s Water activity is defined as the availability of free water in a sample. Only this component takes an active part in the exchange with the ambient humidity colour, taste, shape, and can possibly form the ideal medium for microbiological growth on the texture and appearance. surface (difference in partial vapour of water vapour). Above the sample, the humidity is measured immediately after reaching the humidity balance. The relative humidity is measured in % RH and converted in aw electronically. Introduction to aw measuring In the food, pharmaceutical and cosmetic industry, water activity (aw The optimisation and stabilisation of the product properties require an upper value) is understood as the humidity balance value of a product, which is as well as lower aw value margin. Therefore, constant supervision of this ascertained through its partial vapour of water vapour on the surface. This quality parameter is essential and necessary for efficient production. is depending on the following factors: There are binding regulations in different • Chemical compound regions worldwide with regards to the aw • Temperature value to be met in foods. The measuring • Water content principle applied by Novasina was • Storage environment (T / RH) The variation of oxydation, browning, enzyme activity, checked by the FDA, UNO, WTO, FAO, • Absolute pressure vitamin inactivation & microbial activity AOAC and FOS (EFSA) and found to be • Packing suitable. Oxydation These factors affect the microbial With the LabMaster-aw instrument, following properties: determination of the water content via the e so-called „sorption isotherm“ and aw • Microbiological stability (growth) value is also possible. With this process, • Chemical stability (see table) tion Rat the sample is not destroyed and can be • Content of proteins and vitamins eacR stored accordingly for future checks. A Browning • Colour, taste and nutritional value viable and efficient alternative to the widely • Stability of the compound & durability used water content measurement! Vitamins • Storage and packing Enzymes • Solubility and texture 0.2 a 0.6 a w 0.4 aw w 0.8 aw 1.0 aw Water activity ( Wasseraktivität ) Novasina, the market-leading provider of accurate water activity measuring instruments LabMaster-aw LabPartner-aw Enter the world of water activity! For over 40 years Novasina has been For the first time, the LabMaster-aw has a temperature pre-conditioning developing globally recognised and accurate water activity measuring chamber as well as the aw measuring chamber. As a result, samples can be instruments for quality and research laboratories. The unique measuring brought to the required temperature even before the actual measuring. technology is based on an electrolytic aw value measurement as well as on Therefore, repeated measurements are faster. simple operability and sample conditioning. These are the key factors for The hermetically sealed, temperature-stabilised measuring chamber forms correct and repeatable measurements. Thanks to new functions, the effective the central unit of the system. Integrated in this is the intelligent measuring measuring accuracy and reproducibility could be improved and the scope of unit, which has been developed on an ongoing basis thanks to years of applications extended. Most different types of foods, as well as many research. Measuring is based on a resistive and electrolytic humidity pharmaceutical, chemical and cosmetic products can be checked with the measurement („Novalyte“ technology) and is one of Novasina’s core strengths. Labmaster / Partner-aw system new LabMaster-aw system and their aw value established. Thanks to the use Simple operability using the keyboard interlock, softkey buttons and a large of filter systems to protect the measuring sensor, today even samples with LCD display with graphic capability makes measuring simple. Therefore, access non-aqueous additives such as alcohol, acids/bases or chlorine etc. can be rights and system protection functions can be allocated simply to each operator. measured efficiently and accurately. Such filter systems do not generally affect the measuring of the water activity. The LabMaster-aw system ideally uses Your advantages: the highest physically possible measuring speed. Thanks to modular • Highest measuring accuracy & quick measuring of a value expandability and pre-conditioning, a higher number of samples can also be w measured quickly and accurately. • Simple menu navigation with large LCD display • New, robust and long-term stable a value measuring unit w The completely redeveloped LabMaster/Partner-aw with its simple and clear • Measuring range: 0.03...1.00 aw operation sets a new standard for aw laboratory measuring devices. Thanks to • High reproducibility of the sample measurement modular construction, the system can be expanded by up to 10 measuring chambers. Its unique hardware and software architecture enables highly • User ID and password protection accurate, reproducible measuring results over a wide measuring range. As a • Ultra precision and efficient sample temperature stabilisation result, for the first time, all recommendations and regulations of authorities/ • Pre-conditioning chamber for quick measurements control boards such as HACCP, AOAC, FDA etc. can be met. Each LabMaster- • Simple testing and adjusting functions using Novasina aw has a USB and RS-232 interface for exchanging data with Windows-based PC systems. For data and sample visualisation, analysis and archiving Novasina • SAL-T a standards w offers a tested PC software. The system has an integrated multi-user • External printer connection management system. • Analysis software for PC (Windows) included to scope of delivery • Protection filter systems for the measuring unit against contamination and falsification of the measuring value (chemically/mechanically) w w w. n ova s i n a . c o m The LabMaster / Partner-aw product range With the LabMaster-aw measuring instrument you acquire a lifelong aw laboratory device, which is upgradeable at all times thanks to its advanced technology. Extra LabPartner-aw’s can simply and easily be attached to a LabPartner-aw as additional measuring units. A LabMaster-aw manages and operates up to 9 LabPartner-aw’s using a common kept up to date at all times. communication cable. As a result, for the first time it is possible to measure up If necessary, the aw measuring unit can be replaced quickly and easily by the to 10 samples simultaneously. The intelligent network (fieldbus system) user. The intelligent measuring unit has a memory function and can be independently recognises a new user and correspondingly links this in the calibrated at 7 aw value points. Delivery takes place in each case with a network. For this, only a new identification number (1…9) has to be allocated factory calibration at all points. The tested Novasina humidity standards can to the LabPartner-aw. For long-term storage and management of all measuring be used for checks and recalibration. These are very simple to deal with, data, the system can either be connected to a laboratory printer or to one of long-term stable and generate reproducible aw values. Instead of the sample, the Windows-based software packages provided by Novasina. the standards are used inside the measuring chamber. A set with 6 aw The software of each LabMaster/Partner-aw can be updated using an installed standards is included to each LabMaster-aw. These can be used for several serial interface from your PC via the Internet. In this way, the apparatus can be years depending on storage and use. Specifications LabMaster/Partner-aw systems: Measuring principle: Resistive electrolytic humidity measuring system surfaces temperature measurement and stabilisation Measuring range: 0.03 ......... 1.00 aw (3....100% RH) 0.... 50 °C (32...122°F) measuring chamber actively controlled Measuring accuracy: +/- 0.003 aw (0.04... 0.97aw) +/-0.2 °K Solution: +/- 0.002 aw +/- 0.1°C Control Precision: Measuring chamber +/- 0.1°C (0...50°C) Control range: +/- 25 °K above/below room temp. Supply voltage: 90.... 260 VAC 50 / 60 Hz max. power demand 65 W per apparatus Display: High contrast LCD display 240 x 480 LCD dots with LED background lighting Operation: 20 watertight keyboard interlock 5 softkey buttons Communication: RS-232 and USB 1.0 for PC/printer internal fieldbus systems for extra LabPartner-aw’s Casings: Painted steel casings, weight: 10 kg Dimensions: 268 x 392 x 170 (300) mm Protection class: IP 21 Measuring chamber: Measuring chamber volume 15 ml Intake for standard 3 active sealing barriers under spring pressure Sample dishes (diameter: 30 x 14 mm) Specifics: Pre-conditioning chamber Intake of the sorption intelligent measuring unit isotherm curve using „SI set“ accessories Quick, accurate, safe Thanks to the most modern technology, the LabMaster/Partner-aw system combines speed, intuitive operability, accuracy, soundness and traceability of all measuring results. The unique measuring cell is the core element, which Versatile, variable, modular has been continuously further developed by Novasina for over 40 years. As well as the soundness With the extended measuring range, the aw and long-term stability it is convincing through the value can be determined with different types of Service, accessories, traceability unique reproducibility of measurements. At all times, foods, as well as with pharmaceuticals, and The measuring system does not need special the measuring process can be supervised visually chemical and cosmetic products. The care. If required, the filter systems should on the screen and recorded, analysed and printed accurate measurement of the aw values helps frequently be replaced and the system checked out using the Novasina PC software. Therefore, after not only to control microbiological growth but using aw value standards. The measuring dishes measuring has been completed, the current also to optimise the process control. of the measuring chamber can be removed for measurement values and their variation can be seen The multi-user management function helps cleaning. Each LabMaster-aw includes 50 at all times. Automatic print commands to an external keep the measurement quality at a high level. It sample dishes as well as an aw value standard printer, suitable for connection, allow the also simplifies the operation by different users set (SAL-T). measurements to be completely documented. and upon request, also limits this. The a value measuring method w The test sample is placed in a completely sealed and temperature-stabilised The measuring speed is largely dependent on the sample properties. As a measuring chamber. After sealing, the sample humidifies or dehumidifies result, the ability of how quickly the available free water can be released into the air volume inside the chamber. Only the free water component can do the environment plays a decisive role. The gauge electronics mostly have a this. This exchange takes place until the partial pressure of water vapour basic higher usable measuring speed. saturation = zero. A highly accurate humidity and temperature measuring unit continuously determines the climate conditions of the air within the The phenomenon of a second sorption level is also known with different fatty measuring chamber. If these parameters remain stable over a user-adjustable samples. Firstly the sample „appears“ to run in a state of quasistability in period, the instrument software determines the stable value parameter and order to increase later (possibly hours later) the aw value again (break through converts this into an aw value. As a result, the display continuously shows the „fat barrier“). the current measurement. The following factors play an important role in the measuring accuracy and speed: Zweite Sorbtionsstufe • Temperature of the medium being measured and the measuring chamber • System controllability Scheinstabilität • Tightness of the measuring chamber • Sample preparation • Measuring speed • Measuring accuracy of the humidity value measurement Food industry Typical measuring samples Testing of products and raw materials to optimise • Meat, fish, poultry durability, colour, taste, nutritional value and • Fruit, berries, fruit additives, processing. Final inspection, quality assurance as well • Bread, cakes and pastries, jam, biscuits as packing optimisation regarding durability. • Dried sausage, nuts Optimising process and energy costs during • Butter, yoghurt, quark, cheese production. • Chocolate, cocoa, chocolate bars, sweets • Pasta products, rice, cereals Quality controls in accordance with • Spices, dried soups • Stock cubes, yeast Pharmaceutical industry Typical measuring samples Tests of basic materials, semi-finished and finished products for process properties and possible • Different powders reactivities. Checking further process abilities in the • Granules subsequent process levels. Checking product • Tablets, coated tablets properties regarding the intake and release of free • Gels, creams water into the environment. • Various liquid materials • Specific drugs Quality controls in accordance with HCCP, SOP, FDA, SOP Cosmetic industry Typical measuring samples Quality assurance of basic materials, semi-finished • Powders and finished products. Optimising durability, colour, • Creams and gels fragrance as well as taste and processing. Optimising • Cosmetics packing regarding durability and presentation. • Colours • Conditioning creams Quality controls in accordance with HCCP, WHO, FDA, SOP Some well known companies who associate quality with Novasina: Novasina – Swiss quality, flexibility and competence Since its establishment almost 50 years ago, the Novasina company has specialised in the accurate measuring of air and material humidity. The basis of this was the world’s first, self-developed electronic measuring sensor for measuring humidity. This technology is based on the resistive electrolytic measurement principle. This was further developed and optimised over decades. This measuring principle is generally the most demanding and most accurate. Modern substances and materials allow continuous optimisation and expansion of the area of application of this measuring sensor. Today the highly accurate humidity measurement is among our core competences and forms an important pillar of our success. Intensive research and development further ensures a decisive advantage for us. Novasina sensors and measuring instruments are mainly applied to the area of air and material humidity. This is almost exclusively used in industrial applications as well as in research and development. We fully develop and produce Novasina precision measuring instruments in which our Know-how of many years is always included. We are proud of the „SWISS MADE“ label, which guarantees the highest quality, innovation and longevity. The diversity of our customers, business partners and applications as well as our international orientation makes Novasina the competent partner for demanding humidity measurements in the industrial sphere! Customer uses and innovation always come first with Novasina! For further technical information, see the technical data sheets: Consultation, sales and services: Manufacturer : Novasina AG Neuheimstrasse 12 CH - 8853 Lachen SZ Switzerland Phone : +41/ (0)55-642-67-67 Fax : +41/ (0)55-642-67-70 E- Mail : info@novasina.ch Internet : www.novasina.com Subject to technical changes An ISO 9001 : P 2008 certified company since 1996