The chemicals approvedfor use in foodprocessingoperationsvary widely
fromcountry to country. In general, approved sanitizing agentsare of the
following classifications: chlorine-releasingagents; iodophors; QACs;acid±
anionicsurfactants;fattyacid sanitizers;and peroxides.
Chlorinecompounds
Chlorine compoundshavebroadspectrum antimicrobialproperties. Theyare the
mostwidelyusedsanitizerin US foodprocessing operation.Chlorine-based
sanitizers form hypochlorous acid (HOCl) in solution. HOCl exerts its
germicidal effectby attackingmicrobialmembranesand by inhibiting vital
metabolic processes. The effectiveness of chlorine is affected by pH,
temperature, and organic load.The majordisadvantagesto chlorine compounds
are corrosivenessand worker healthand safetyissues.
Iodinecompounds
Iodophors are the classof sanitizersthat contain the halogen iodine. The
compounds existin many formsbut are most oftenformulated witha surfactant
as a carrier.Their antimicrobialactivity is achievedby way of directhalogenation
of cellularproteinsand throughdamageto the cell wall.Iodophors are active
againstbacteria,yeast,molds,protozoa, and viruses. The majordisadvantages to
usingiodophors are temperature and staining.Iodineevaporates at temperature in
excess of 120 ÎF (49 ÎC). Thus iodophors are limited to relatively low-
temperature applications.Staining of somesurfaces, especially plastic,have
beenreported in applicationswherethis iodophorshavebeenused.
Quaternaryammonium compounds
QACsare surface-active compoundsand it is generally acceptedthattheir
germicidalactivity is relatedto interactionswith the microbial cell wall.The
germicidal activities of these compounds are formula dependent and it is
therefore difficult to speakin general termsabouttheiroveralleffectiveness.
QACscan be formulated to be effectiveagainstbothGram-positiveand Gram-
negative bacteria.Theyalso haveactivityagainst yeastand molds.QACsare also
activeand stableovera broadrangeof temperatures.The majordisadvantagesto
usingthis class of compounds includeexcessive foamproduction in automated
systems, incompatibility withwetting agents,and low hardwatertolerance.
Acid±anionicsanitizers
Acid±anionicsanitizersare surface-active compounds.Theyare formulated with
an inorganic acid and a surfactant.Acid±anioniccompounds achievegermicidal
activity by way of interactionand subsequentdamage to the microbial cell wall.
Thesecompoundsare effectiveagainst vegetativebacteria. Themajordis-
advantageof using acid±anionicsanitizershas to do withtheirlow activity
againstyeastand moldsand also to the fact that theyare effective overa very
narrowpH range(pH 2 to 3). Becausetheyare surfactantstheymayalso result
in excess foamproductionwhen usedin automatedcleaningsystems.
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