Juice plates

MATERIALS

105 g agar

100 g sucrose

6 g methyl paraben (Tegosept)

1 L apple juice

Autoclave

Flasks (one 6-L, one 2-L, five 1-L)

Plates

Stir plate and stir bar

Stoppers for 1-L flasks

1. In a 6-L flask, stir 105 g of agar into 3 L of H₂O.
2. In a 2-L flask, stir 100 g of sucrose and 6 g of methyl paraben into 1 L of apple juice and shake well.
3. Autoclave these flasks separately for 45 min. Sterilize five 1-L flasks by autoclaving (these flasks will be used for pouring the plates).
4. Slowly pour the sucrose/apple juice solution into the agar solution, add a stir bar, and stir for ~15 min (use settings of stir speed 9 and heat 6).
5. Pour ~800 mL of the combined solution into each of the autoclaved 1-L flasks. Stopper each flask so a skin does not form on the solution and take care not to agitate them to avoid the formation of bubbles. Once cooled slightly, pour the agar solution into the plates.