14.3.4 Step4: Materialsof construction
An extensivelist of constructionmaterials is available for packagingequipment.
The specificexclusion of materials is mentionedin the ISO 14159 norm,
paragraph5.2. Under normalconditionsthe most prominent issuesare the use of:
∑ stainless steelas basicconstruction material;
∑ foodapprovedmaterials, Foodand DrugAdministrationlist;
∑ foodgradelubricants.
14.3.5 Step5: Design and fabrication of equipment
The design process is supported by a number of guidelinesthatoffer the
designerexamplesand designsuggestions.Thedocuments published by the
EuropeanHygienicEngineeringand DesignGroup(EHEDG)provideverygood
references.Another very good reference is the so-called `sanitary design
checklist'set up by the American MeatInstitute. Thischecklistoffers an
overview of the critical issuesthat needreviewduring the designprocess.It is
basedon 10 principles:
- Cleanable to a microbiologicallevel.
- Madeof compatiblematerials.
- Accessible for inspection, maintenance and cleaning/sanitation.
- No liquidcollection.
- Hollowareas hermeticallysealed.
- No niches.
- Sanitaryoperationalperformance.
- Hygienicdesignof maintenance enclosures.
- Hygieniccompatibilitywithothersystems.
- Validation cleaningand sanitationprotocols.
Eachequipment manufacturercan makean interpretationof the issueson this
list and definethe requiredhygienic design standards suitablefor the defined
application.Applicationscouldbe dividedin groups, e.g. convenienceproducts,
ready meals, mealcomponentsor slicedproducts.
The characteristics of these productsare, e.g., wateractivity,after-packaging
pasteurisation or not, sterilisationor not, distribution throughthe cool chainor as
frozen food. Other relevant characteristics are pH, packaging conditions
(modifiedatmosphere or vacuum), normallifetime(shelf-lifefrompackaging
to retail sales)and openshelf-life(afteropening packfor consumption).
The following are the most importanthygienic designissues:
∑ Thehygienic requirements of the packingdepartmentand the packing
process.
∑ Critical areasfor hygienic designof the packingsystem.
∑ Performanceof the gas supplyto the packingmachine.
∑ Packing machinerequirements.
∑ Conveyorswithproduct contact.
234 Handbookof hygiene controlin the foodindustry