IJCA - Volume 3 - Flipbook - Page 62
60 The International Journal of Conformity Assessment
Food item for implementation veri昀椀cation. This
laboratory will need to select one (food) item within
the scope of the validation, which also is within the
scope of laboratory application of the user laboratory.
For veri昀椀cation of this method, the laboratory chose
vanilla ice cream, because it is easily homogenized
for dividing into test portions.
Figure 1 shows that this laboratory tests (food)
items from three different (food) Categories: Heat
processed milk & dairy product; Infant formula and
infant cereals; Multi-component foods or meal
components; and one “Other” non-food Category:
“Environmental samples.”
This laboratory will need to test items from all four
of these categories to complete veri昀椀cation of this
method for use in their laboratory.
STEP 2: REVIEW METHOD VALIDATION DATA, AND
CHOOSE (FOOD) ITEMS FOR THE VERIFICATION STUDY
Once again, this laboratory will 昀椀rst need to con昀椀rm
that the food and non-food items they routinely test
have been (fully) validated by either the AOAC®O昀케cial
Method of AnalysisSM program and/or a method
Certi昀椀cation organization that follows the protocol
de昀椀ned in ISO 16140-2:2016.
AOAC validation data
The AOAC® O昀케cial Method of AnalysisSM
2003.01 study report for Neogen Petri昀椀lm
Enterobacteriaceae Count Plate was published in
the Journal of AOAC and can be accessed on the
AOAC website.9 (This method has no Performance
Tested Method [PTM] data because the method
was fully validated prior to creation of the AOAC
PTM program.)
ISO 16140-2:2016 validation data
Neogen Petri昀椀lm EB Plate was also validated via
NF VALIDATION by AFNOR Certi昀椀cation per the
ISO 16140-2:2016 protocol. The AFNOR Certi昀椀cate
3M 01/06-09/97 and summarized validation study
report can be found on the AFNOR Certi昀椀cation
website.
Food items for (food) item veri昀椀cation. This
laboratory will need to choose one challenging
(food) item from each of the three identi昀椀ed (food)
Categories, and the one non-food item Category
to complete veri昀椀cation of this method. For this
example, the laboratory chose vanilla ice cream
with chocolate pieces and almonds; dehydrated
milk powder; and ready-to-cook spinach and cheese
tortellini to verify each of the three (food) categories
in the validated method claim; the laboratory chose
swabs with Letheen broth for veri昀椀cation of the one
non-food category.
(Food) items chosen for both implementation and
(food) item veri昀椀cation are highlighted in Figure 4.
STEP 3: IMPLEMENTATION VERIFICATION – INTRALABORATORY REPRODUCIBILITY STANDARD
DEVIATION (sIR)
Implementation veri昀椀cation for quantitative methods
is achieved by determining the Intra-laboratory
reproducibility standard deviation, expressed as sIR
(Intra—meaning within one lab, versus Inter—meaning
between several labs, as is conducted during a full
method validation).
For this study, the laboratory will choose one (food)
item within the scope of the method validation, which
also falls within the scope of laboratory application.
In this instance vanilla ice cream was chosen. The
Figure 4. The “User” Laboratory (food) items – Quantitative method
THE USER LABORATORY – (FOOD) CATEGORIES
Heat Processed Dairy
Infant Formula
Multi-Component/Composite Foods
Environmental Samples
Vanilla ice cream
Infant cereal with wheat,
oats, sugar, rice
Frozen cheese
pizza
Ready-to-cook
pasta
Sponges with Letheen
broth
Vanilla ice cream with
chocolate swirls
Dehydrated milk powder
Frozen supreme
pizza
Ready-to-cook
spinach and
cheese tortellini
Swabs with Letheen
broth
Vanilla ice cream with
chocolate pieces and
almonds
Whey-based dairy infant
formula
Frozen sausage
and anchovy pizza
Ready-to-cook
cheese tortellini
