Category: EN – newsitem

First MicroVal certificate for commercial sterility detection method

MicroVal has recently issued the certificate for Neogen’s Soleris Commercial Sterility Testing Vials (NF-105) for the determination of commercial sterility in UHT treated milk and dairy alternative plant drinks. These are ready-to-use media vials containing a broth able to grow aerobic, mesophilic microorganisms (bacteria, yeasts and moulds) that are able to grow on an aerobic plate count at 30°C. Results from the validation data showed that the alternative method can be used as a rapid and sensitive testing method for commercial sterility monitoring of UHT treated milk and dairy alternative drinks.

Campden BRI has carried out the validation study of this alternative method, based on ISO 16140-2:2016. The Soleris NF-105 testing vial has been validated against the Codex Alimentarius, Code of Hygienic practice for milk and milk products (CAC/RCP 57-2004), Annex B Microbiocidal control measures Section 2.2 process management for UHT treatment using ISO 4833-1:2013 for the plate count at 30°C. In this validation, the method was used to determine a defined threshold of product contamination of greater than ≤ 10cfu per 0.1ml as defined in the European Directive 92/46 annex C chapter 2 for ultra-high temperature (UHT) milk.

The certificate and the accompanying summary report, number 2021LR100, can be found under ‘issued certificates / alternative methods’.

New Certificate for iQ-Check™ STEC VirX

In June 2022, MicroVal has approved the issuing of the certificate for Bio-Rad’s iQ-Check™ STEC VirX kit for real-time PCR detection of virulence genes in Shiga toxin-producing Escherichia coli. ADRIA Développement has carried out the validation study of this alternative method, based on ISO 16140-2:2016, for the scope of raw meat products (excluding poultry) and raw dairy products.

STEC outbreaks are commonly associated with the consumption of raw meat, particularly beef, but also with dairy products. A sample positive for both stx1/stx2 and eae targets typically requires further testing for the identification of the major E. coli serogroups. The iQ-Check STEC VirX Kit, based on a multiplex real-time PCR system, allows the detection of the stx1/stx2 and eae virulence genes within a few hours after microbiological enrichment.

The certificate and the accompanying validation report, number 2021LR96, can be found under ‘issued certificates / alternative methods’.

Twelfth certificate for Nissui’s Compact Dry

MicroVal has approved the issuing of the certificate for Compact Dry LM by Nissui. This is a chromogenic medium for the detection and enumeration of Listeria Monocytogenes. Campden BRI has carried out the validation study of this alternative method, based on ISO 16140-2:2016, for the scope broad range of foods, consisting of the following categories, plus environmental samples:

  1. Meat and poultry products (RTE/RTRH)
  2. Dairy products (raw and heat processed)
  3. Fresh produce and fruit
  4. Seafood & fishery products
  5. Multicomponent foods

The Compact Dry LM has been validated against ISO 11290-1 and against ISO 11290-2. This extensive validation study has resulted in two separate certificates for the detection of Listeria Monocytogenes  and for the enumeration of this species. Both certificates, numbers 2020LR91a+b can be found under ‘issued certificates / alternative methods’.

During the past years, MicroVal has already validated and certified the Compact Dry chromogenic medium for:

  • Bacillus cereus – Compact Dry BC (2019LR87)
  • E. coli – Compact Dry EC (2008LR04/05, previously MV0806-004LR & MV0806-005LR)
  • Enterobacteriaceae – Compact Dry ETB (2008LR02, previously MV0806-002LR)
  • Enterococcus – Compact Dry ETC (2014LR48)
  • Pseudomonas aeruginosa – Compact Dry PA (2017LR66)
  • Staphylococcus aureus – Compact Dry X-SA (2008LR14)
  • Total coliforms – Compact Dry CF (2008LR03, previously MV0806-003LR)
  • Total viable count – Compact Dry TC (2007LR01)
  • Yeast & moulds – Compact Dry YM (2008LR10, previously RQA2008LR10)
  • Yeast & moulds – Compact Dry YMr (2016LR61)

New certificate for foodproof Enterobacteriaceae plus Salmonella Detection LyoKit – 5’Nuclease

MicroVal has approved the issuing of the certificate for BIOTECON diagnostics GmbH’s foodproof Enterobacteriaceae plus Salmonella Detection LyoKit – 5’Nuclease. The validation study is carried out ADRIA Développement and is based on ISO 16140-2:2016.

The foodproof Enterobacteriaceae plus Salmonella Detection LyoKit – 5’Nuclease is a PCR kit for the qualitative detection of Enterobacteriaceae plus simultaneous identification of Salmonella spp. DNA using real-time PCR instruments. The validation of this alternative method has been performed in combination with the foodproof StarPrep One Kit and the foodproof StarPrep Three Kit in both single tube and 8-strip formats. For this validation study the following categories were tested:

  • infant cereals,
  • infant formula with or without probiotics and ingredients
  • production environmental samples.

The certificate and the accompanying study report, number 2020LR90, can be found under ‘issued certificates / alternative methods’.

New certificate for Kylt Salmonella spp. 2.0

MicroVal has approved the issuing of the certificate for Kylt Salmonella spp. 2.0 by AniCon Labor GmbH. Campden BRI has carried out the validation study of this alternative method, based on ISO 16140-2:2016, for the detection of Salmonella spp in 4 different categories:

  1. Raw meat and ready to cook meat products,
  2. Raw poultry and ready to cook poultry products,
  3. Environmental samples and
  4. Primary production samples.

Kylt Salmonella spp. 2.0 has been validated against ISO 6579- 1:2017 (Horizontal method for the detection, enumeration and serotyping of Salmonella. Part 1: Detection of Salmonella spp.)

Kylt Salmonella spp. 2.0 a polymerase chain reaction (PCR) based assay that targets Salmonella specific DNA split into 3 stages:

  1. Sample enrichment in Buffered Peptone Water (BPW) prewarmed to 37°C and incubated for 16h at 37 ±1°C.
  2. DNA extraction using 1 of the 2 DNA extraction methods listed in the manufacturer’s protocol
  3. Analysis of DNA extracts by real time PCR using selected PCR platforms. The study evaluated 2 PCR programmes for Salmonella detection;

The certificate and the accompanying study report, number 2017LR78, can be found under ‘issued certificates / alternative methods’.

New certificate issued for Neogen’s One Plate Listeria

MicroVal has approved the issuing of the certificate for Neogen’s One Plate Listeria (OP-L). Campden BRI has carried out the validation study of this alternative method, based on ISO 16140-2:2016, for the enumeration of two different targets, Listeria monocytogenes and Listeria spp., against the reference method ISO 11290- 2:2017. The method, One Plate Listeria, has been validated for the scope of a broad range of foods.

One plate Listeria (OP-L) is a chromogenic medium for the enumeration of Listeria spp. and L. monocytogenes. Characteristic colonies of L. monocytogenes appear blue to blue-green and are surrounded by an opaque halo. Characteristic colonies of Listeria spp appear blue to blue-green with or without an opaque halo. This method has the option to enumerate the target organsism in different plating formats – 1ml pour plate and 0.1ml spread plate.

The certificate and the accompanying summary report, number 2019LR89, can be found under ‘issued certificates / alternative methods’.

New Certificate for Thermo Scientific Oxoid Cronobacter Precis

In June 2021, MicroVal has approved the issuing of the certificate for the Thermo Scientific Oxoid Cronobacter Precis method. The validation was conducted by Laboratoire Microsept. Besides the ISO 16140-2 validation study, Laboratoire Microsept  also interpreted part of the results obtained during the ISO 16140-2 validation study of the ThermoScientific SureTect Cronobacter PCR Assay, initially performed by ADRIA Dévelopement.

Cronobacter Precis is a new chromogenic-based workflow. It offers an alternative to the horizontal method for the detection of Cronobacter spp. (ISO 122964:2017) through a fast screening of the samples after an overnight enrichment and a selective plating onto Oxoid Brilliance CCI Agar Base.

The method has been validated for the scope of infant formula (10 g), environmental samples (25 g or surface sampling), infant formula, infant cereals and related ingredients (up to 375 g).

The certificate and the accompanying summary report, number 2020LR93, can be found under ‘issued certificates / alternative methods’.

Renewed certificates GENE-UP E.coli O157:H7 and Compact Dry ETC

MicroVal has renewed the certificates for bioMérieux ‘s GENE-UP E.coli O157:H7 and Nissui’s Compact Dry ETC. Both certificates are now valid until April 2025.

GENE-UP E.coli O157:H7 2 (ECO and ECO 2) is a real-time Polymerase Chain Reaction (PCR) assay for the qualitative detection of E.coli O157:H7 in food samples. The method was first validated by th expert lab ADRIA Développement in 2017. The scope of the validation consisted of fresh and frozen raw meats, cured and fermented meats, vegetables, raw dairy products using a specific protocol, raw meats (except poultry) using a short protocol (25 g and 375 g sample size) and environmental samples. The renewed certificate, registered as study number 2015LR59, can be retrieved form the MicroVal website, together with the supporting validation report.

Compact Dry ETC is a ready to use, selective and chromogene plate for the detection and enumeration of Enterococcus. The method was first validated by the expert lab Campden BRI in 2017 for the scope of broad range of foods. The renewed certificate, registered as study number 2014LR48, can be retrieved form the MicroVal website, together with the supporting validation report.

MicroVal Expert opinion about AOAC Validation Coronavirus Test Kits

AOAC INTERNATIONAL announced that it has issued five certificates of validation for proprietary test kits that detect SARS-CoV-2 on stainless steel surfaces. These test kits have passed the evaluation required by the globally recognized AOAC Research Institute’s Performance Tested Methods (AOAC-PTM) Program, which implemented an Emergency Response Validation (ERV) process to accelerate the evaluations. The MicroVal experts have evaluated the approaches taken by the AOAC-PTM validation program for detection methods of the SARS-CoV-2 on environmental surfaces, and fully support this AOAC initiative.

Below you can find some more information from AOAC on this program.

The COVID-19 crisis has fundamentally changed our way of life and the everyday life in the professional and domestic environments. It is obvious this will have other impacts in the future.

SARS-CoV-2 is a public health issue. Direct transmission of the virus from person-to-person is the main route of contamination. However, some food industries have faced contamination issues among co-workers[1]; stability of SARS-CoV-2 on various surfaces have been demonstrated[2], and transmission of the virus from contaminated surfaces might be possible[3].

Emergency responses were set up to support the food industry. Methods have been developed to detect SARS-CoV-2 in food production environment to evaluate the efficiency of control measures designed to eliminate the virus from surfaces. AOAC INTERNATIONAL has activated an accelerated program to evaluate test kits for detecting coronavirus on surfaces.

For food manufacturers, contract laboratories, and others in the food supply chain, the certifications provide independently validated tests they can use to ensure their

sanitation protocols are effective and to provide a culture of safety for their essential employees.

The AOAC Performance Tested Method program (PTM) includes multiple steps:

  • An in-silico analysis was developed to evaluate the quality of the primers and probes of the test kits. This innovative approach in the framework of method validation makes sense as thousands of SARS-CoV-2 genomes are free available, and the databases continue to expand.  In the validation study, there were 15,764 accessions evaluated for inclusivity, and 65 near neighbors and environmental background organisms for exclusivity.
  • The matrix study was run with stainless steel test areas inoculated with intact SARS-CoV-2 virus (USA_WA1/2020). The samples were prepared by a single independent laboratory. After proper surface sampling, the US Centers for Disease Control and Prevention (CDC) method and the candidate method were run in an unpaired data study design to attempt to detect the virus on the surfaces. The acceptability of the alternative method is evaluated by the Probability of Detection approach[4].
  • The Robustness, Product Consistency and Stability studies will be run in a final step early 2021, as kits from different production batches are required. Robustness parameters evaluated will be specific to each method.

The involved AOAC reviewers are recognized experts in the field.

AOAC Volunteer Expert

William Burkhardt, FDA/CFSAN/OFS/DSST

AOAC Expert Reviewers

Jacqueline Woods, FDA/CFSAN/OFS/DSST/MHSB

Efi Papafragkou, FDA/CFSAN/OARSA

Sanjiv Shah, EPA/ORD/HSMMD

John SantaLucia, Wayne State University

Chengzhu Liang, Qingdao Customs District Laura Rose, CDC/DDID/NCEZID/DHQP

[1] https://www.newfoodmagazine.com/article/112889/coronavirus/

[2] https://www.forbes.com/sites/robertglatter/2020/08/23/covid-19-coronavirus-can-survive-on-frozen-meat-and-fish-for-up-to-3-weeks-study-finds/#1e8975128877

[3] https://doi.org/10.1016/j.tifs.2020.08.020

[4] http://www.eoma.aoac.org/app_h.pdf

Renewed and extended certificate for Assurance GDS E. coli 0157:H7 Tq

In October 2020, MicroVal has approved the renewal and extension of the certificate for Assurance GDS E. coli 0157:H7 Tq, manufactured by Merck MilliporeSigma. This genetic detection system is an automated nucleic acid amplification system for the detection of pathogenic E. coli 0157:H7 in foods, ingredients and environmental samples. The renewal and extension study was conducted by Qlaboratories.

The Assurance GDS E.coli 0157:H7 Tq was first validated in 2016. For the renewal project, all data was reanalysed according to the statistical guidelines outlined in ISO 16140-2:2016 to determine if the acceptance criteria were met.

An additional alternative confirmation method for E. coli O157:H7 was also added to the scope. Necessary supplemental testing was conducted following a sensitivity outline for the categories that are already claimed following ISO 16140-6: 2019.

The renewed and extended certificate, registered as study number 2015LR49, can be retrieved form the MicroVal website, together with the supporting validation report.