It is unrealistic,then,to assume that the foodprocessing industry of Upton
Sinclair'sday would havehad a meaningful understanding of theseimportant
scientific developments. Mr Sinclair's writings do suggest, however, a
fundamental understanding by some withinthe industryof that era, of the
effectivenessof heat in minimizingthe outwardmanifestationsof putrefaction.
He describes the use of `white hot pokers' for treatingthe overtmanifestations
of spoilage in de-boned hams. Heatand or hot waterwouldcertainly havebeen
the media of choice duringthat epoch,for bothcleaning and disinfectingfood
processingequipment.It is also clearfromthe literaturethat the preponderance
of cleaningactivities,if not all, wouldhavebeen carriedout on a clean-out-of-
place (COP)basis, i.e. removedfrom its normalplace of use in a food
processingoperationspecifically for the purposesof cleaning.
Since 1906 therehavebeenmany great innovationsin microbiologyand food
processing. These technological advances have led the development of a
scientificbasis for cleaningand disinfecting foodprocessingequipment.And
whilemuch has changed in the foodprocessingindustrysince1906,it remains a
fact that hot waterand heat are still widely usedcleaningand disinfecting agents
within the industry. Moreover,COPcleaningremains a leadingmethodfor wet-
cleaning,food processingequipment. Sinks,dishwashers, tote-washers, and
similar devices are widely usedfor cleaningpipes,pumpparts,valves, utensils,
and the other portableappurtenancesusedin the massproductionof foods
intended for humanconsumption.
Thischapterwill providea reviewand discussionof the commonmethods
and typesof COPcleaningcurrentlyin use by the foodindustry.The chapter
willalsofocuson current best practices and methods for developingand
validating an effectivescienceand risk-basedCOPcleaningprocess.
28.2 Best practicesin developingan effectiveCOPprocess
The simpleact of extracting and delivering machineparts,portable utensils,or
other implementsintoan agitated tankfilledwithhot waterand a cleaning
compoundwillnot ensurethat theyare properly cleaned. Successful COP
cleaningrequires knowledgeof all the factors that maylimitor otherwise
compromise the effectivenessof the applied cleaningprocess.
A process,by definition,is a seriesof planned activities that have been
carefullyconstructed to achieve specificobjectivesor outcomes.In the case of a
COP process, the objectives are the removal of objectionable odors, food
residues, otherextraneous debris and undesirable microorganismsfrom the
contact surfaces of foodprocessingequipment.On the face of it, COPcleaning
is a verystraightforward processconsisting of five basicunit operations: pre-
rinse; wash;post-cleaningrinse;sanitization (disinfection in Europe); and final
rinse. Thesebasicprocedures constitute the fundamental elements of all wet-
cleaningprocesses (cleaningby hand,dishwashingmachines, CIP and COP). It
is noteworthythat,whilethe elements of the processare identical,the outcomes
446 Handbookof hygiene controlin the foodindustry