Pre-Sterilized Malt Extract Agar

Directions for use: NOTE: Do not open the jar of pre-sterilized agar until instructed to do so in the following set of directions.

1. In a pan add enough water until the level of water is the same as the agar in the jar. Leave lid on jar tightly sealed.

2. Place jar in the water.

3. Bring water to boiling.

4. Continue to boil until all agar is completely liquefied. More water may need to be added to pan as it is boiled away.

5. Completely clean and disinfect work area where you plan to pour agar. We recommend a HEPA (High Efficiency Particulate Air) filter system. If this is not available the next best is a glove box. Although contamination rates are much higher, success can be achieved.

6. With all agar liquefied, carefully move it to your clean area. Move petri dishes to area. Wipe outside of petri dish bag with alcohol soaked towel. Do the same to jar containing agar. Carefully cut open petri dish bag and remove petri dishes. Be careful of your movements. Petri dishes come in a plastic sleeve which allows them to remain sterile until opened or punctured. Separate them in to two stacks of ten. One 250 ml jar will pour ten dishes. Pour agar into all dishes once opened. Starting at the bottom of the stack lift the lid and stack, slowly at a angle and pour enough agar to cover the bottom. Remember that as you lift the lid air rushes in to fill the space. If this air is filled with contaminate spores you agar will become contaminated. Continue pouring equal parts into remaining dishes.

7. Wait until agar cools and becomes firm again, then it is ready to use or to store until a future time.

8. If poured dishes are to be stored they should be protected from air currents. They can be placed in a plastic container with a resealable lid. Temperature fluctuations will cause condensation to occur. Generally this is not a problem unless it is excessive. They can be stored for a indefinite period of time providing they do not become contaminated. The more time that passes, the greater the risk for airborne contamination to occur.

9. Agar in original jar will last for many weeks, perhaps as long as a year. To insure purity it is recommended to use as soon as possible, this is the reason for the expiration date.