8.4.3 Productdecontamination
Freshproduce and the outerpackagingof variousingredientsmayneedto be
decontaminatedon entryinto highrisk.Decontaminationis undertakenusing
validated and controlledwet systems,usinga washingprocess incorporatinga
disinfectant(usually a quaternaryammoniumcompound)or dry systems,using
UV light.
As withheat barriers, decontaminationsystems needto be installed withinthe
low/high-risk barrier to minimise the free space around them. As a very
minimum, the gap aroundthe decontamination systemshould be smaller than
the productto be decontaminated.Thisensures that all ingredients in highrisk
must havepassedthroughthe decontaminationsystem and thus musthavebeen
decontaminated.
For companiesthat also haveovenswithlow-risk entrance and high-risk exit
doors, it is also possibleto transferproduct fromlow to highrisk via theseovens
using a shortsteamingcycle that offerssurfacepasteurisation without `cooking'
the ingredients.
8.4.4 Otherproduct transfer
All ingredientsand product packagingmustbe de-boxed and transferredinto
highrisk in a way that minimises the risk of cross-contaminationinto highrisk.
Some ingredients,such as bulkliquids that havebeenheat-treated or are
inherentlystable (e.g.oils or pasteurised dairyproducts), can be pumped across
the low/high-riskbarrier directly to the pointof use. Dry,stablebulkingredients
(e.g.sugar)can also be transferredinto highrisk via sealedconveyors.
For non-bulk quantities,it is possible to openingredientsat the low/high-risk
barrier and decant themthroughinto highrisk via a suitabletransfer system(e.g.
a simplefunnelset into the wall),into a receivingcontainer. Transfer systems
should, preferably, be closablewhennot in use and shouldbe designedto be
cleanedand disinfected,fromthe high-risk side, prior to use as appropriate.
8.4.5 Packaging
Packaging materials(filmreels,cartons, containers,trays,etc.) are best supplied
to site 'double bagged'. Whencalled for in highrisk,the packagingmaterial is
brought to the low/high-riskbarrier, the outerplasticbag removedand the inner
bag and packagingenters into highrisk through a suitablehatch.
The hatch,as withall openings in the low/high-risk barrier,should be as
small as possible and shouldbe closedwhennot in use. Thisis to reduce air flow
throughthe hatchand thus reducethe air-flowrequirements for the air-handling
systems to maintain high-risk positive pressure. For some packagingmaterials,
especiallyheavyfilmreels,it maybe requiredto use a conveyor system for
moving materials throughthe hatch.An openingdooror, preferably, double
doorairlockshould be usedonlyif the use of a hatchis not technicallypossible,
and suitableprecautionsmustbe takento decontaminatethe airlockafteruse.
160 Handbookof hygiene controlin the foodindustry