Frequently Asked Questions

FoodChek™’s MICT® System

  1. Which FoodChek™ assays have AOAC approval?
    Answer: The Listeria, Salmonella and E. coli O157 assay cassettes are AOAC validated.
  2. How does the FoodChek™ MICT® Reader work?
    Answer: The FoodChek™ MICT® Reader instrument performs quantitative biochemical assays in a lateral flow format using super paramagnetic particles as the label. FoodChek™ assays, labeled with magnetic particles and read on the FoodChek™ MICT® Reader instrument, demonstrate superior dynamic range and detection sensitivity when compared to conventional optical detection instrument.
  3. How do I know if the reader is functioning accurately?
    Answer: A Verification Test Cassette is included with the MICT® System. You can verify the MICT® Reader’s measurement accuracy and performance with the supplied verification cassette. This cassette contains three stable and calibrated test regions on one test strip. They are used to verify the instrument’s internal calibration (accuracy) and performance (noise).
  4. What happens if my Verification Test Cassette is damaged?
    Answer: Replacement Verification Cassettes are available through any one of our MICT® System product distribution partners. Please contact us to obtain the distributor for your geographical area.
  5. How big is the FoodChek™ MICT® Reader?
    Answer: The FoodChek™ MICT® Reader’s dimensions are L 33cm x W 25cm x H 23cm and it weighs 3.3kg.
  6. What is the operating temperature and operating humidity for the instrument?
    Answer: The FoodChek™ MICT reader requires an optimal operating range of 5 to 35º C and 20 to 85% non-condensing relative humidity.
  7. What happens if the FoodChek™ MICT® Reader fails?
    Answer: If the instrument fails, FoodChek™ will provide you with a temporary loan unit while your reader is repaired.

Actero™ Enrichment Media

A.  General Information and Usage/Applications

  1. What is the difference between Actero™ Elite Enrichment Media and Actero™ Universal Enrichment Media?
    Answer: FoodChek™’s Actero™ Elite Enrichment Media (Actero™ Elite) is a patented bacterial growth medium for the detection of Listeria species (spp.), Listeria monocytogenes and Salmonella spp. The advantages of Actero™ Elite are: (i) the sample enrichment timeline phase is up to 30% to 70% faster to achieve results; (ii) single-step enrichment that reduces sample handling; and (iii) specific for the target microorganism despite even with competing flora. These advantages result in remarkable savings in time – improved workflow, higher throughput of samples and release products sooner to the market. Actero™ Elite can be used by ANY food processor involved in food safety pathogen testing regardless of what testing system they use. You only need to validate the food or environmental sample by using Actero™ Elite on the particular testing system prior to implementing its use in your food safety program.
    FoodChek™’s Actero™ Universal Enrichment Media (Actero™ Universal) consist of over 130 standard media formulations that can be used in any testing system for the detection of Listeria.spp., Listeria monocytogenes, Salmonella spp., yeasts, molds, and coliforms. The advantages of Actero™ Universal are: (i) high quality; (ii) accurate for the target microorganism; and (iii) competitive pricing.
    Both Actero™ Elite Enrichment Media and Actero™ Universal Enrichment Media are manufactured in the United States and Europe with high quality ingredients to ensure optimal performance and integrity of product.
  2. What is Actero™ Elite Enrichment Media?
    Answer: FoodChek™ Actero™ Elite Enrichment Media (Actero™) is a patented bacterial growth media that makes the sample enrichment timeline phase up to 30% to 70% faster to achieved results. Actero™ can be used by ANY food processor involved in food safety pathogen testing regardless of what testing system they use.
  3. Who would use Actero™?
    Answer: Commercial testing laboratories, fresh food processors and meat packers who perform any food safety pathogen testing on food or environmental samples.
  4. Why would I use Actero™ Elite?
    Answer: Actero™ Elite gives the fastest “time-to-results”, single-step enrichment, selective for the target microorganism, cost competitive, high quality, and offers superior enrichment performance.
  5. What packaging configurations can Actero™ be purchased in?
    Answer: In dehydrated formats of 500g, 2 KG, 10 KG and custom pouch sizes for dehydrated media. 5 L, 10 L, and 20 L for Liquid Media.
  6. How many Actero™ Elite products are available?
    Answer: FoodChek™ currently offers six (6) Actero™ Elite formulations: i) E. coli; ii) Listeria; iii) Salmonella; iv) Salmonella/STEC v) STEC; and vi) mTSB.
  7. How do I obtain a SDS sheet for Actero™ Media?
    Answer: SDS sheets are available on the FoodChek™ website at for each product or by contacting us.
  8. Has Actero™ Elite been validated by the AOAC International?
    Answer: FoodChek™ Actero™ Elite Listeria has received AOAC Performance Tested Method (PTM™) certification License Number 111201 and Actero™ Elite Salmonella has received AOAC Performance Tested Method (PTM™) certification License Number 041403.
  9. How long is the enrichment incubation period for Actero™?
    Answer: It depends on the organism and sample being enriched. FoodChek™ has found that Actero™ incubation times are dramatically faster at up to 30% for Listeria and up to an amazing 70% for Salmonella, when compared with competitors and the official test methods.
  10. How do I get a sample of Actero™ Media?
    Answer: You can request sample through the FoodChek™ website or by contacting your FoodChek™ Territory Manager or VWR Sales Associate.
  11. Can FoodChek™ customize packaging of Actero™ media to fit my facilities requirements?
    Answer: FoodChek™ and VWR will work with you to optimize product packaging for your facility. This is normally a request for large volume customer but we are willing to provide quotes for unique situations as well.
  12. Can I schedule automatic shipments of Actero™ Media to make sure I do not run out of material?
    Answer: Yes. To initiate scheduled shipments of Actero™ or other FoodChek™ products, contact your VWR representative and they will guide you through the procedure.
  13. How do I obtain Actero™ Technical Data/Information Sheets?
    Answer: They are posted on the FoodChek™ website at for each of our products.

B.  Preparation/Reconstitution, Sampling and Storage

  1. What grade of water should I use to re-constitute the dehydrated Actero™?
    Answer: Always use microbiological quality water (type 3). Ideally the water should be distilled, de-ionized, or passed through a reverse osmosis system. Tap water should not be used because of impurities.
  2. What are the recommended storage conditions for Actero™?
    Answer: The dehydrated medium should be kept at 12 to 25 degrees C, in tightly closed bottles, in a dry and well ventilated place, and protected from direct light. The expiry date is indicated on the package.
    IF the medium has been autoclaved, it can be stored at 2 to 8 degrees C for up to 45 days, in tightly closed bottles and in a cool dry place.
    IF the medium has NOT been autoclaved, it should be used immediately.
  3. What is the shelf life of the product once it has been opened?
    Answer: There is not an established shelf life of the product once it has been opened because the storage conditions are too much of a variable from one place to another. Humidity, temperature, the number of times that the bottle has been opened, etc., are among some of the parameters that could affect the medium after several months. However, as long as the appearance of the product does not change and it is still free-flowing, you can use it.
  4. Does light affect the performance of the medium?
    Answer: The medium is light sensitive; however, it can support normal light for a few days.
  5. How do I protect the medium from light?
    Answer: You can put the prepared medium in amber or opaque bottles that are specifically designed to prevent the light to enter the container. You can also envelop your clear bottles with aluminum foil or store the prepared medium in boxes.
  6. How long is the enrichment incubation period for Actero™ Elite?
    Answer: It depends on the organism and sample being enriched. FoodChek™ has found that Actero™ Elite incubation times are dramatically faster at up to 30% for Listeria and up to an amazing 70% for Salmonella when compared with competitors and the official test methods.
  7. The Actero™ Listeria Enrichment Media has been left at room temperature overnight. Could this affect its performance?
    Answer: The Actero™ Listeria Enrichment Media will not be affected by a few days of storage at room temperature.
  8. The package inserts for Actero™ Listeria Enrichment Media specifies that the medium should be pre-heated to 29, 32, 35 or 37 degrees C. How long can the media stay pre-heated?
    Answer: The medium can be pre-heated overnight (16 to 22 h) at 37 degrees C without any problem.
  9. What are the best conditions for the preparation of the Actero™ Salmonella Enrichment Media?
    Answer: Add the dehydrated medium to the water and set your hotplate/stirrer to 190 degrees C and shake for 5 to 10 minutes, then autoclave. This should be enough to reach the optimal dissolution.
  10. Can we supplement the Actero™ Salmonella Enrichment Media several days prior to utilization?
    Answer: Yes, the supplemented broth is stable for two (2) months when stored at 2 to 25 degrees C and away from light. However, be sure to add the supplements in aseptic condition to avoid bacterial contamination.
  11. At what point does the malachite green get added to the Actero™ Salmonella Enrichment Media?
    Answer: The malachite green supplement is added after the autoclaving, just prior to use.

C.   QC Testing

  1. Is Actero™ performance QC tested?
    Answer: Yes, each lot of Actero™ is quality and performance tested. Certificates of Analysis are available on the FoodChek website with the product listings or can be obtained upon request by contacting us.

D.   Performance/Appearance Issues

  1. Is there a stable target pH value for the Actero™ Listeria prepared media?
    Answer: After preparation and autoclave, the pH should be at 7.0 ± 0.2.
  2. We observed a little deposit in our 5 L Actero™ Listeria MediaBox™. Is this normal?
    Answer: It appears that, over time, a very thin deposit can occur. In this case, it could be enhanced by the fact it is a 5 L MediaBox™ instead of a 1 L, which we usually work with. However, when you mix the bottle or the bag, this light deposit should completely dissolve in the medium. If not and you still see turbidity, it is likely due to bacterial contamination. If this happens, do not use the MediaBox™.
  3. We are seeing a little precipitate in the bottle after preparation of the Actero™ Salmonella Enrichment Media. Is this normal? Does this affect the performance of the media?
    Answer: Yes, it is normal to observe a slight precipitate after preparation and the precipitate does not impact the performance of the media. However, we do recommend that you swirl the bottle to disperse the precipitate prior to dispensing the prepared media into your samples.
  4. Over time in using the Actero™ Salmonella Enrichment Media, we have seen this type of variation from lot to lot in reference to precipitate. Is this something that is common and to be expected?
    Answer: Concerning the precipitate, it is effectively common with this medium. Little variations between lots are expected, although be assured that each lot is thoroughly tested to ensure they reach the highest standard of quality and performance.
  5. Sometimes we observe an insoluble film or precipitate after autoclaving (110 degrees C for 15 minutes). Is there any way to avoid this? Does this affect the performance of the media?
    Answer: The insoluble film you are seeing after autoclaving may be caused by overheating of the medium or more probably by use of glassware that is not perfectly clean and rinsed. This could be caused, for example, by the salt or the detergent used in the dishwasher or if the glassware was not rinsed with the appropriate water. So, when the problem occurs, verify your sterilization and cleaning process to be sure that it is still effective as this may effectively have an impact on the performance of the media.

General Suggestions to Solve the Problem

a.  Glassware Cleaning

–  Is your glassware clean?

–  Are there no residues or visible particles?

–  Are you using a dishwasher?

–  Did you verify that your dishwasher is working well?

–  Did you try to wash a bottle by hand and use it to prepare the medium?

–  Have you tried another dishwasher?

–  Have you tried another lot of detergent when you washed the glassware?

–  Did you rinse your glassware after washing?

b.  Water

–  Did the water you used appropriate (Type 2 water is good)?

–  Did you verify the conductivity of the water when you took the water from the system?

–  Did you try water from an alternative source to prepare the medium?

–  Are you using reservoirs to store water and are they clean?

c.  Sterilization

–  Did you verify if your autoclave is working fine?

–  Did you try to sterilize the medium with another autoclave?