This is a pre-mix that just needs to be added to water, shaken to distribute ingredients, and pressure-cooked for the appropriate time and pressure (usually 30-60 minutes at 15 psi). It will pour 20-25 standard-size, 90mm plates, depending on the depth of media.
Gellan Gum is an excellent alternative to traditional agar-based recipes. It tends to be clearer, more rigid, and has a higher melting temperature (great for shipping in warm climates).
The pre-mix recipe for 500 ml pack is as follows:
4g Gellan Gum (low acyl)
8g LME (light malt extract)
0.5g Nutritional Yeast
0.5g MgSO4 (magnesium sulfate)
0.05g Dye
The total weight is 13g per pack (for 500 mL total volume). The whole pack is just added directly to 500 mL of tap or purified water, and then sterilized before pouring pre-sterilized polystyrene (PS) plates. Alternately, the pre-mix can be thoroughly dissolved by heating and then dispensed into glass Petri dishes prior to pressure cooking/autoclaving.