Robust Sterile Air Filtration Reduces FermentationCost of Ownership

OverviewFood and feed ingredient producers usingfermentation as the basis of their process facepressures from food manufacturers for lowerpricing and increased output without compromisingquality. These fermentations are among the mostchallenging in the industry with 35 to 350 m3

(1,236 to 12,360 ft3) fermentor batches followedby complex purification steps. Reaching yieldtargets is a key factor for competitive advantage.One microbial contamination can lead to yielddecrease or even complete fermentation batchloss. Contamination may also result in capacityloss and increased cleaning costs that mayjeopardize overall profitability of the plant.

Contamination control of all process fluids makesthe difference. The purity of compressed air, usedat up to hundreds of standard cubic meters perminute, is critical during seed, propagation andproduction fermentation.

The Challenge

A major amino acid producer needed to improvefermentor contamination control while loweringoperating costs. Due to insufficient protection oftheir production fermentors, they had experiencedmillion dollar losses due to batch contamination.

Bacteria selected for the production of aminoacids can be highly sensitive not only to microbial,but also to bacteriophage (bacterial virus)contamination. The treatment of fermentor inlet airis a critical control point (CCP), where microbialsterility of air and freedom from phages is adeterminant parameter to protect the yield. Toprotect the fermentor contents, sterilizing grademembrane air filters additionally validated for highlevels of phage removal were required.

A significant consideration was filtration operatingcosts, especially as they related to cost persterilization cycle. Due to the need for repeated in situ steam sterilization cycles, it was importantfor the customer to understand the degree ofmechanical resistance and life expectancy of thefilters as well as the nature of other filterperformance claims.

The Solution

Pall Corporation offers expertise and capabilities insterile air filtration for food ingredient fermentations,with its Emflon® filter cartridges. They have beenproven cost-effective in numerous installationsaround the globe due to their reliability andefficiency.

For high volume air applications, the hydrophobicpolytetrafluoroethylene (PTFE) membrane of theEmflon PFW cartridge provides the sterilizing gradefiltration characterized by extremely high titerreductions for microorganisms and phagesrequired to prevent contamination risk.

The comprehensive and rigorous validationprogram of the Emflon PFW filter, described in aTechnical Performance Document, was the basisof discussions to demonstrate filter performanceand reliability. Test methods, sample sizes andresults regarding liquid challenge testing, aerosolchallenge testing with bacteria, spores, phages,and sodium chloride particles at various conditions

App

licat

ion

Bul

letin

Emflon PFW filter cartridge

(forward and reverse flow, high humidity), andmechanical resistance under normal operating andmulti-cycle steaming conditions illustrated therobustness of the performance claims. Subsequentcustomer steam sterilization tests confirmed thehigh strength of Emflon PFW.

Cost per sterilization cycle is directly influenced bymulti-cycle steaming performance. Multi-cyclesteaming tests are a routine part of sterilizinggrade gas filter validation. Emflon PFW is validatedfor 165 1-hour steaming cycles at 140 ºC (284 ºF)in the forward direction. Such performance claimsare the outcome of rigorous testing on multipleproduction filters, involving various test parametersdesigned to prove the mechanical resistance of the filters.

Further contributing to lowering the cost ofownership is the large filtration surface area, at 0.8 m2 (8.6 ft2) per 10 inch cartridge. This results in low initial pressure drop, which leads directly to compressor energy savings as well as longerfilter life.

In addition to the benefits of the Emflon PFWcartridge, Pall Scientific and Laboratory Servicesran customized validation studies on specificbacteriophages critical to some of the customer’s products. Air line design audits andrecommendations for sterilization procedures andintegrity tests completed the service offering.

Inlet Air

Emflon PFW

Compressed Air Supply Point of Use Filtration Exhaust Filtration

ProductFermentor

ConditioningCompression

DistributionNetwork

Aftercooler,Coalescer,

Dryer,Filters

Pre-Filter Pre-Filter SterileFilterPipework

to End UseEquipment

Sterile Filter

F

Figure 1: Schematic of compressed air pipework to fermentor and exhaust

The Benefits

The combination of exceptional product featuresand Pall’s strong technical services translated intocost-saving benefits for the customer at a criticalcontrol point in their process.

• Minimized risk of contamination and reliableproduct protection, resulting in improvedfermentation yield

• Lowered cost of ownership due to high filtermechanical resistance during multiple steamingcycles

• Compressor energy savings due to high flowrates and low pressure drop

• Rigorous performance validation to supportquality assurance program

• Customized laboratory studies forbacteriophage removal performance

• Market-dedicated service expertise to optimizethe air filtration process

About Pall Corporation

Pall Corporation is a global filtration, separationand purification leader providing solutions to meetthe critical fluid management needs of customersacross the broad spectrum of life sciences andindustry. We work with our customers to advancehealth, safety and environmentally responsibletechnologies.

Pall Food and Beverage provides products andservices to ensure product quality and maintainprocess reliability in beverage and food production.Our solutions also assist in consumer protection,the reduction of operating costs and wasteminimization.

Pall Food and Beverage

25 Harbor Park DrivePort Washington, NY 11050 +1 516 484 3600 telephone+1 866 905 7255 toll free US

foodandbeverage@pall.com

© Copyright 2013, Pall Corporation. Pall, and Emflon are trademarks of Pall Corporation. ® Indicates a trademark registered in the USA. Filtration. Separation. Solution.SM and Total Fluid ManagementSM are service marks of Pall Corporation.

FBABFAENa April 2013

Visit us on the Web at www.pall.com/foodandbev

Pall Corporation has offices and plants throughout the world. For Pall representativesin your area, please go to www.pall.com/contact

Please contact Pall Corporation to verify that the product conforms to your nationallegislation and/or regional regulatory requirements for water and food contact use.

Because of technological developments related to the products, systems, and/orservices described herein, the data and procedures are subject to change without notice.Please consult your Pall representative or visit www.pall.com to verify that thisinformation remains valid.