normally 1% sodiumhydroxide, is heatedto 75±80ÎC and the cleaning timeis
15±20min.The equipmentis rinsedwith cold waterbeforethe acid treatment is
performedat approximately60±70ÎC for 5 min.The effectof chlorine-based
agents can be dividedintothree phases: loosening of the biofilm fromthe
surface, breakageof the biofilmand the disinfective effectof the activechlorine.
The cleaning solutionsshouldnot be re-usedin processes in orderto achieve
total sterility because the reused cleaning solution can contaminate the
equipment.Single-phaseCIP is morecommonly usednowadaysbecausethe
processingindustry wants to savetime.In single-phase cleaningprocedures the
timeit takesto carryout one cleaningprocess,normally the acid treatment,and
a rinsingstep can be saved(Costertonet al., 1985; Wirtanenet al., 2000a). The
photobacterialtest can be usedto test that rinsinghas beenperformedproperly
(Lappalainenet al., 2003).3.5 Future trends
The foodand drinkindustry is the leadingmanufacturingsectorin Europewith
production representing 13%of the totalof all industrial manufacturers in the
EU and withan annualturnoverof about®700 billion.Threemainemployersin
the EU employ more than4 millionpeople. This positionillustratesthe major
economic roleof the foodand drink industry, a very diversesector that is
characterised by the variety of its activities, its elaborated products and
structures.
Microbiological and chemical issueswill be especiallyimportantfor the safe
production of feed,foodand packagingmaterial in the future.A numberof
outbreaksin recentyearshaveseriously damagedthe Europeanconsumer's
trust in food safetyand thereforeknowledgeof product safety, including
equipment hygiene, is of the utmost importance both for the product
manufacturer and for the consumer. Development of optimal pathogen
managementstrategies requires knowledgeof pathogencontamination routes,
the consumer, howthe foodbecomes a vehiclefor diseasetransmissionand the
differentiation of risksand hazards.Hazards in the foodindustrycan be of
microbial, e.g. biofilm formation, biological, chemical, physical or
informational origin.The function of risk assessmentis to giveobjectiveand
relevant information about specifiedrisks. An important problem in risk
assessmentat the manufacturinglevelis that a morequantitativesystematic
approach should be used:the risk assessmentprocedureshould be basedon
scientificknowledgeand performedin a teamthathas the knowledge and
experienceneeded to perform the reliableevaluation of risks (Wirtanen &
Raaska, 2004).Therefore, reliable monitoring systems, which can provide
information about microbial growth on-line,directly andin real time, are
required withinthe process. The methodsshouldbe basedon opticaland
electro-chemical measurements, ion mobilityand infraredtechniquesas wellas
bioluminescence. The successful transfer of these techniques for on-line
60 Handbookof hygiene controlin the foodindustry