Micro Filtration of Dairy Products Brochure

Leading Technologies. Individual Solutions.GEA FiltrationMembrane FiltrationMicrofiltration of Dairy ProductsMicrofiltration of Dairy ProductsCross-flow microfiltration technology is rapidly gaining prominence inthe processing of dairy ingredients. Microfiltration, along with othermembrane filtration processes like ultrafiltration, reverse osmosis andnanofiltration, is making it possible to produce products with veryunique properties and functionalities.The practical dairy applications of microfiltration are often limited by severe fouling of the membrane, which results in flux decline andchanging of the retention characteristics. Microfiltration is a pressuredriven process where the Trans Membrane Pressures (TMP) are in the order of 1 to 2 bar which is very critical to the performance of the processes. This makes the plant design and control of operatingparameters very important. In addition, advances in membranes, both organic and inorganic types,have made these processes technically possible and economicallyviable. While the following are only a few examples of potentialseparation processes, several new applications are being developed.SporesBacteriaProteinsLactose & SaltsWaterFatProteinsLactoseSaltsWaterCaseinWhey ProteinsLactoseSaltsWaterBacteria and Spores Reduction in Fluid Dairy ProductsDemand for products with low bacteria and spore counts is increasing. Examples of these areExtended Shelf Life (ESL) milk, pretreatment of cheese milk to prevent gas formation duringthe cheese aging process, production of skim milk and whole milk powders with very lowbacteria and spore counts, and better microbiological quality of Whey Protein Concentrates.Plants equipped with special ceramic membranes can give at least a Log 4 (99.99%) reductionin bacteria and spores depending on the loading in the feed.Reduction of Fat in Whey Protein Concentrates (WPC)The limitation of fat removal from whey by mechanical separation results in high fat contentin WPC. This high fat level limits the maximum protein content in the final WPC powder,usually 80-84% depending on the feed quality. Whey Protein Isolates (WPI) require reductionof fat content in the final product to < 0.5 %. This can be accomplished by reducing the fat content further than using mechanical separationonly by microfiltration with either ceramic or spiral wound membranes. The choice dependson a variety of parameters such as capital cost, operating cost, and others.Fractionation of Casein and Whey Proteins in Skim MilkSeparation of casein from whey proteins in skim milk and its concentration gives anopportunity to fortify cheese milk without increasing the whey protein content. This has a positive influence on increasing the capacity of cheese making equipment without affecting the quality of cheese. As an added benefit, whey proteins produced by such a process have some unique functional properties since they have not come in contact with cheese starter, rennet or cheese additives.Advances in ceramic microfiltration membranes make this process feasible. The process can be also accomplished to a lesser degree by spiral wound membranes.Microfiltration MembranesSeveral recent developments in the membrane construction technologyhave been a key to the advances in microfiltration processes. Ceramicand spiral wound microfiltration membranes each find their uniqueplace in these processes. For every application, the different membranesneed to be evaluated carefully to assess the advantages and disadvan-tages of each. Spiral Wound Organic MembranesUltrafiltration, nanofiltration and reverseosmosis spiral wound organic membraneshave been the workhorse of separationprocesses in the dairy industry. Recent advances in membrane materials andelement construction, coupled with plantdesign techniques, have made possible theiruse for microfiltration processes. Comparedto inorganic membranes, they have their placein a number of microfiltration applications.GEA Filtration can evaluate both inorganicand organic membranes for your application. Ceramic MembranesMicrofiltration processing for most of theapplications in the dairy industry is verysensitive to the Trans Membrane Pressure(TMP). Deviation of the TMP from a narrowoptimum range can cause an adverse effecton the retention coefficients and often causeirreversible fouling.Conventional microfiltration techniques havea disadvantage due to the hydrodynamicpressure drop from the inlet to the outlet ofthe flow channel caused by the recirculatingflow. As illustrated in the accompanyingdiagram, this causes a decline in the TMPalong the flow length resulting in: • Decline in permeate flux along the length of the flow channel.• Formation and migration of the gel layer from the inlet of the flow channel.This heterogeneity reduces the quality of separation, shortens running time andtherefore can reduce the attractiveness of the application.Uniform Trans-Membrane Process Pressure (UTP) has been developed byhydrodynamicaly creating a pressure gradient on the permeate side of themembrane to match the feed side. Thisresults in a constant TMP along the length of the flow channel. The control system to maintain these parameters is very critical to the process.Non-Uniform Permeate FluxMembrane Support LayerActive Membrane LayerRetentate PressurePERMEATEPermeate PressureRETENTATEFe ed FlowC o n v e n t i o n a l M F P r o c e s sMembrane Support LayerActive Membrane LayerPERMEATERETENTATEFe ed FlowPermeateFlowRetentate PressurePermeate PressureU T P P r o c e s sVariable MembraneSupport LayerActive Membrane LayerPERMEATEPermeate PressureFe ed FlowRetentate PressureRETENTATEV a r i a b l e S u p p o r t PERMEATEPermeate PressureFe ed FlowMembraneSupport LayerVariable Active Membrane LayerRetentate PressureRETENTATETAMI ISOFLUX® Ceramic MembraneRecently TAMI Industries of France hasintroduced a new solution … ISOFLUX®. Thismembrane has been designed by varying theactive layer thickness along the length tocompensate for the pressure gradient. Thistechnique makes the process much simpler byeliminating the need for additional permeateside components. Control of such a processis also quite simple making the operationvery stable. ISOFLUX® membranes are avail-able in 0.14, 0.2, 0.45, 0.8 and 1.4 micronporesize. While standard layer gradients are available, the possibility of varying thegradient to match the process exists.In addition, ISOFLUX® membranes utilizenon-circular cross section flow channels to be able to increase the membrane area perelement and housing. This dramaticallyreduces the plant physical size and itsholdup volume. Several inplant trials have resulted in higherfluxes, better retention and longer runningtime obtained by ISOFLUX® membranescompared to other techniques. GEA Filtration has a worldwide exclusivearrangement to use ISOFLUX® membrane fordairy applications. ISOFLUX is a registeredtrade mark of TAMI Industries.ISOFLUX® is the registered trademark of TAMI IndustriesA Reliable PartnerGEA Filtration is part of GEA, an international process engineering leaderin the life sciences industry with more than 150 companies operatingworldwide. As a team member with other technology leaders within thegroup, GEA Filtration is uniquely positioned to provide both customizedmembrane filtration plants as well as complete process lines specificallytailored to each customer’s specific needs and requirements.Global Experience, Local PresenceGEA Filtration specializes in cross-flow membrane filtration technologies,namely Reverse Osmosis (RO), Nanofiltration (NF), Ultrafiltration (UF)and Microfiltration (MF). We also offer a wide range of system configura-tions and membrane types to provide you with the best possible solutionfor each application.GEA Filtration has extensiveexperience in the followingindustries: • Dairy• Food including Sugar,Starch and Sweetener • Beverage • Pharmaceutical /Biotechnology• Environmental / ChemicalMulti-disciplined teams atdedicated GEA Filtrationcenters in USA and Denmarkcan provide the followingvalue-added services:• Pilot trials and applicationdevelopment• System scale-up• Project engineering• Process integration• Controls and automation• System fabrication• System installation and start-up• Service and plant audits• Replacement membraneinventory.GEA Filtration also has a wide selection of pilot plants in all membrane types available for on-sitetrials at customer’s location,from bench top models tocontinuous, semi-automatedpilot plants designed forlarge flow scale-up capability.For more details on the specifications for each of these pilot units, consult our website at www.geafiltration.com.P i l o t P l a n t s GEA FiltrationGEA Filtration • Niro Inc. • 1600 O’Keefe Road • Hudson, Wisconsin 54016, USA • TEL 1 715 386 9371 • FAX 1 715 386 9376E-MAIL info@geafiltration.com GEA Filtration • GEA Liquid Processing Scandinavia A/S • Noerskovvej 1b • DK-8660 Skanderborg, DenmarkTEL 45 70 15 22 00 • FAX 45 70 15 22 44 • E-MAIL post@gea-liquid.dkGEA Filtration • GEA Wiegand GmbH • Einsteinstrasse 9-15 • 76275 Ettlingen, Germany • TEL 49 7243 7050FAX 49 7243 7053 30 • E-MAIL info@gea-wiegand.de WEB www.geafiltration.comFor more information on all the products andservices provided by GEA Filtration, accessour website www.geafiltration.com.