Part2:Determinationofthereliabilityofcolonycountsofparallelplatesandsubsequentdilutionsteps
Thisstandarddescribesaroutineprocedurefortheevaluationofresultsoftheenumerationofmicroorganismsusingcolony-countmethodswithsubsequent10-folddilutionstepsandoneplateortwoparallelplateswithineachdilutionstep.
Thisroutineprocedureisappliedregularlyineachlaboratoryperformingcolonycounts.Itprovidescriteriafortheacceptabilityofdifferencesbetweentheresultsfromparallelplatesandsubsequentdilutionsteps,asfollows.
Theresults(colonycounts)obtainedfromparallelplatesarecomparedwithtabulatedlimitsforgivencolonycounts.Iftheselimitsareexceeded,atechnicalproblemwhenperformingtheparalleldeterminationsmaybeindicated.
Theresults(sumsofcolonycounts)oftwoparallelplatesoftwosubsequent10-folddilutionstepsarecomparedwithtabulatedlimitsforgivensumsofcolonycounts.Iftheselimitsareexceeded,atechnicalproblemwhenperformingthedilutionsmaybeindicated.
Ifthelimitsmentionedaboveareexceededinmorecasesthanexpected,thisindicatesthatthetestprocedurelacksreliability.
ThisstandardisonlyavailableinEnglish.
注:若需要正式出版文本,请底部扫码咨询客服。
食典报订阅号
食典通服务号
客服号