FOOD TESTING ASSAYED MICROORGANISM PREPARATIONS
The EZ-FPC™ (Food Process Control) Microorganisms are produced and lyophilized to produce a preparation with a stated assay value. The intended use is as process control challenges in qualitative (presence/absence) and quantitative (enumeration) food safety and quality tests.
Standards and guidelines recommend the importance of, or mandate, quality assurance programs in microbiology food safety and quality testing laboratories.
Recommendations or mandates include qualitative (presence/absence) and quantitative (enumeration) process controls. Because microorganisms can pose a serious threat of foodborne disease or can provide a measurement of food quality, the methods employed in the detection or enumeration of these microorganisms must demonstrate the ability to recover low concentrations or provide enumerations of microorganism target populations in a consistent and reproducible manner.
Each EZ-FPC™ Microorganism consists of:
- one (1) vial each containing ten (10) pellets of a single lyophilized strain
- detailed instructions, and
- a certificate of assay
MATERIALS REQUIRED BUT NOT PROVIDED
A sterile forceps or tweezer is required for the removal of an individual pellet and placement into the enrichment broth or primary dilution fluid.
In accordance with each individual laboratory's SOP, the enrichment broths, dilution fluids, and additional required testing materials for qualitative or quantitative test methods must be provided.
STORAGE AND SHELF LIFE
For optimum shelf-life, upon receipt, store the product in its original intact container at 4-8ºC. away from direct light.
This product should not be used if there is evidence of: excessive dehydration, contamination, damage to the vial, improper storage, or the expiration date has passed. Product is light and temperature sensitive; protect from light, excessive heat and freezing.
The expiration date applies to the product in its intact packaging when stored as directed.
Using proprietary techniques in producing the EZ-FPC™ Microorganisms, a known and stable concentration of bacteria can be manufactured in the lyophilized configuration. The freeze-dried cultures are formed into individual pellets which are supplied in glass vials. The source of the strains is the American Type Culture Collection (ATCC®).
These products are for laboratory use and is to be used only by adequately trained and qualified laboratory personnel. Observe approved biohazard precautions and aseptic techniques. All laboratory specimens should be considered infectious and handled according to "standard precautions". The "Guideline for Isolation Precautions" is available from the Centers of Disease Control and Prevention at www.cdc.gov/ncidod/dhqp/gl_isolation.html.
For additional information regarding specific precautions for the prevention of the transmission of all infectious agents from laboratory instruments and materials, and for recommendations for the management of exposure to infectious disease, refer to CLSI document M-29: Protection of Laboratory Workers from Occupationally Acquired Infections: Approved Guideline.
Sterilize all biohazard waste before disposal.
Refer to the keyword "Precautions", in the Hardy Diagnostics software program HUGO™, for more information regarding general precautions when using culture media.
Refer to the keyword "MSDS", in the Hardy Diagnostics software program HUGO™, for more information on handling potentially hazardous material.
DIRECTIONS FOR USE
1. Remove the vial of lyophilized pellets from refrigerated storage and allow the unopened vial to equilibrate to room temperature (22ºC. to 25ºC.)
2. With a sterile forceps, remove one (1) pellet and place into a volume of enrichment broth or dilution fluid as stated in the laboratory SOP. It is essential that the enrichment broth or dilution fluid be rewarmed to 34ºC. to 38ºC.
ONLY ONE PELLET MUST BE USED
3. Immediately recap the vial and return the remaining lyophilized pellets to refrigerated storage (4ºC. to 8ºC).
4. Hydration and Incubation.
|Qualitative Process Control|
|Incubate the inoculated enrichment broth according to the laboratory SOP. At least once during the incubation of the enrichment broth (i.e. following 30 minutes of incubation), mix the flask to ensure an even distribution of the dehydrated microorganism population.|
|Quantitative Process Control|
|Incubate the inoculated dilution fluid at 35ºC. for thirty (30) minutes. Following incubation, mix the inoculated dilution fluid thoroughly.|
5. Proceed with the complete qualitative or quantitative testing procedure as set forth in the laboratory SOP.
6. Upon completion of the procedure, record the test results to provide performance documentation.
The decision to perform in-house quality control is the responsibility of each individual laboratory. Quality control functions might include:
|a) determination of pellet-strain purity|
|b) determination of pellet-strain identification|
|c) validation of pellet-strain CFU|
A 'Certificate of Assay' is provided with each EZ-FPC™.
A. Assay Value
The assay value of each lyophilized preparation is of known and defensible quantity and quality. As soon as these preparations are processed, the assay value can be influenced by the test method, manipulations, dilutions, transfers, enrichment, selective media, incubation, analyst proficiency, plate count versus MPN, interpretation, calculations, CFU/gm versus CFU/ml, etc. Laboratories must be made aware of these influences. If a test method or analyst proficiency does have an influence on the test result, the lyophilized preparation should not be subjected to scrutiny. Rather, the lyophilized preparation is doing exactly what it is suppose to do and the test or analyst must be subjected to review and corrective action.
B. Qualification Studies
The EZ-FPC™ Microorganisms have an application in pre-qualification and re-qualification studies.
|Components of a food sample may have an inhibitory influence on the recovery of potential food-borne pathogens.|
|a. Using a single pellet of an EZ-FPC™ Microorganism, seed the food sample and immediately proceed to the enrichment step.|
|b. Using a second pellet of the same EZ-FPC™ Microorganism, directly seed the enrichment broth in the absence of the food sample.|
|c. At appropriate intervals, plate counts can measure what, if any, inhibitory influence the different food samples might have on the recovery and detection of the target microorganism.||2. Re-Qualification|
|Based on favorable test results during the pre-qualification studies, at appropriate intervals, a single pellet of an EZ-FPC™ Microorganism can be used to seed a specified food sample to document consistent and reproducible test results.|
C. Verification and Validation
1. Qualitative Analysis
Automated presence/absence equipment or detection devices commonly require several logs of growth to 'trigger' a positive result. A protocol similar to the "Qualification Studies" can be employed to verify or validate the ability of equipment or device to detect low-concentrations of target microorganisms. In addition to positive or negative detection of the seeded sample versus the seeded enrichment broth without the food sample may provide valuable sample matrix validation documentation.
2. Quantitative Analysis
Automated enumeration equipment commonly requires the detection of a metabolite, conductivity, or impedance in relationship to time to generate enumeration test results. A protocol similar to the "Qualification Studies" can be employed to verify or validate the ability of automated equipment to enumerate the population of a target microorganism. The enumeration of a seeded food sample in the dilution fluid versus a seeded dilution fluid without the food sample may provide valuable sample matrix validation documentation.
1. FDA. 1995. Bacteriological Analytical Manual, 8th ed.
2. Compendium of Methods for the Microbiological Examination of Food, 3rd ed. 1992.
3. Standard Methods for the Examination of Dairy Products, 16th ed. 1993.
4. Package Insert, MicroBioLogics, Inc., St. Cloud, MN, 56303.
This document is provided for general product information only. It does not replace the manufacturer's product insert. Always refer to the actual product insert for procedural use and for most recent product information.
ATCC is a registered trademark of the American Type Culture Collection.
EZ-FPC is a trademark of MicroBioLogics, Inc., St. Cloud, MN, 56303.