Preparation of medium

Medium Preparation method Usage Culture temperature / time

Potato dequilose agar medium
  1. 1) For 200 ml of purified water
    →Dissolve 7.8g of medium.
  2. 2) The medium is autoclaved at 121 ° C for 15 minutes and poured into a petri dish.
Yeast / mold count measurement, isolation culture 25℃（room temp.） / Up to 5 days

YGC agar medium
  1. 1) For 200 ml of purified water
    →Dissolve 8g of medium.
  2. 2) Sterilize with high pressure steam at 121 ° C for 15 minutes and pour into a petri dish.
 Selective separation of fungi and measurement of fungal count 25℃（room temp.） / Up to 4 days

WL ordinary agar / differential medium
  1. 1)
    A) For 1 liter of purified water
    →Dissolve 77g of medium.
    B) For the mixed solution (600 ml of purified water + 400 ml of filtered tomato juice)
    →Dissolve 77g of medium.
    C） Adjust medium A) to pH 5.5 to 6.5 with 30 ml of 1% sodium hydrogen carbonate solution as needed.
  2. 2) The medium is autoclaved at 121 ° C for 15 minutes and poured into a petri dish.
 A) Measurement of the viable count of yeast for brewing such as beer
B) Suitable for testing alcohol mash specimens
C) Measurement of yeast count in bread and distilled liquor
 25 ° C / aerobic culture / up to 2 weeks
30 ° C / aerobic culture / up to 2 weeks
30 ° C / aerobic culture / up to 2 weeks
  1. 1) When 0.004 g of cycloheximide is added to the medium, it becomes a WL differential medium.
  2. 2) The medium is autoclaved at 121 ° C for 15 minutes and poured into a petri dish.
 When the number of yeast contained in the sample is large, it is used in combination with WL ordinary agar and used for bacterial tests like WL ordinary agar. Aerobic culture