Compact Dry YMR Yeast and Mold Rapid plates | Compact Dry YMR Yeast and Mold Rapid | Shimadzu

1. Overview of yeasts and moulds (Yeast and Mold)

– Yeasts and moulds (Yeast and Mold) are spore-forming microorganisms.
– These spores withstand harsh conditions such as pH, drought and extreme temperatures.
– Yeast and Mold is an indicator of the cleanliness of the bioaerosol environment in various manufacturing plants.
– Failure to comply with the levels of yeasts and moulds (Yeast and Mold) that a production area can tolerate will lead to spoilage problems in food.
– Yeasts and moulds (Yeast and Mold) can easily spoil food because they tolerate environmental conditions (for example a water activity below 0.85 and as low as 0.45).
– Therefore, based on the regulations of the food and drug authorities, it is a very important practical parameter for food and beverage processing, and part of the environmental system through air sampling.
– For this reason, a procedure for testing yeasts and moulds (Yeast and Mold) is recommended, and the Compact Dry rapid yeast and mould plate offers convenience to the user thanks to the advantage that no complex preparation of culture media, equipment or consumables is required.
– All the technology used for this Compact Dry Yeast and Mold Rapid plate is a pre-poured medium. The user only needs to extract the sample, pipette it onto the plate and take it to incubation.

2. Advantages of using the Compact Dry yeast and mould plate (Yeast and Mold Rapid)

– Simple, easy-to-use procedure, with no need to prepare consumables or complex equipment.
– Easy to use, and no time lost training users.
– The compact dry plate is easy to store thanks to its packaging of 4 plates per pack.
– Results are quite accurate, easy to analyse, and available after 48-72 hours.
– Colonies can be isolated for biochemical testing.

3. Testing procedure on the Compact Dry Yeast and Mold Rapid plate

– Aseptically weigh 10.0 g of sample, or use a pipette to take 10.0 ml (for samples that are a solution), and place it in a suitable sterile container (for example a sterile sample bag, a dilution bottle or a Whirl Park bag).
– Add 90.0 ml of diluent to reach a 1:10 dilution and homogenise the sample. Adjust the pH if necessary. The diluent usually recommended is Butterfield's phosphate buffer, maximum recovery diluent and other suitable diluents depending on BAM.
– If necessary, the sample can be diluted further.
– Open the lid of the Compact Dry Yeast and Mold Rapid plate. Take 1.0 ml of the diluted sample with a micropipette and place it in the middle of the Compact Dry plate. The sample solution will spread automatically. Close the lid of the plate.
– Invert and incubate the compact dry Yeast and Mold Rapid plate under the specific incubation conditions (Per AOAC International standard: 25 ± 2°C for 48 to 72 hours, per Microval and NordVal standards: 25 ± 1°C for 3 days).

* Reading the results and counting colonies

- Select plates with 10-150 colonies.

- Colony morphology:

- Yeasts: green, white, opaque white colonies

- Moulds: colonies with hyphae and the colour characteristic of each mould species.

* The procedure is illustrated in pictures as follows:

Note:

- A small number of yeast colonies may not be green

- The formulation of the Compact Dry plate contains antibiotics to inhibit the growth of bacteria.

- A plate with more than 300 CFU may make the whole colony area turn green/blue. In this case the sample needs to be diluted.

- After the results have been read, the plate is autoclaved (121 °C/ 30 minutes) before it is disposed of.