CULTURE MEDIA FOR CULTIVATION OF MICROORGANISMS 



479 



1655. Tanner's Whey Peptone Agar 



Constituents : 



1. Whey. 1000.0 cc. 



2. Agar (1.5%), 15.0 g. 



3. Peptone (Witte) (1.0%) .... 10.0 g. 



4. Glucose (2.0%) 20.0 g. 



Preparation : 



(1) Add a few drops of acetic acid to boil- 

 ing milk until the casein is pre- 

 cipitated. 



(2) Filter. 



(3) Neutralize or bring to -t-1.0%. 



(4) Dissolve 1.0% peptone, 2.0%, glucose 

 and 1.5%o agar in (2). 



(5) Clarify with whites of eggs or dry 

 albumin. 



(6) Tube. 



Sterilization: Method not given. 

 Use: Isolation of B. vulgaricus. 

 References: Heinemann and Hefferan (1909 



p. 310), Tanner (1919 p. 71), Stitt (1923 



p. 38). 



1656. Committee A. P. H. A. Whey Peptone 

 Agar 



Constituents: 



1. Whey 1000.0 cc. 



2. Peptone (1.0%) 10.0 g. 



3. Agar (1.5%) 15.0 g. 



Preparation: 



(1) Add sufhcient rennet to a liter of 

 skimmed milk at 41°C. to cause 

 coagulation (1.0 cc. of liquid rennet 

 in 20.0 cc. distilled water). 



(2) When the curd is firm cut in fine 

 pieces and steam for 40 minutes. 



(3) Strain thru muslin. 



(4) Adjust the reaction of the whey 

 +1.5 and add 1.0%, of dry peptone 



and 1.5% shredded agar. 



(5) Steam for one hour. 



(6) Readjust to an acidity of 1.5%. 



(7) Cool to 60°C. 



(8) Clarify with egg. 



(9) Counterpose and boil over a free 

 flame for 5 minutes. 



(10) Filter thru cotton or a hot washed 

 plaited filter paper. 



(11) Tube. 



Sterilization: Sterilize 15 minutes for 3 



successive days in steam. 

 Use: General culture medium for milk 



analysis. 



Variants : 



(a) Fulmer and Grimes cultivated yeast 

 found in cream and butter on a me- 

 dium prepared as follows: 



(1) Dissolve 1.5%o agar and 0.5%, pep- 

 tone (or omit peptone) in 1000.0 cc. 

 of whey obtained from skim milk 

 by coagulation with rennet. 



(2) Filter thru absorbent cotton. 



(3) Tube in 10.0 cc. portions. 



(4) Sterilize for 20 minutes at 

 15 pounds. 



(5) When used as a plate medium, add 

 1.0 cc. of 1.0% tartaric acid solu- 

 tion to each petri dish, to keep 

 down bacterial growth. For use 

 as solvents add 1.0 cc. of (4) to 

 each tube after cooling to not 

 above 45°C. 



(b) Cunningham gave the following 

 method of preparation: 



(1) Warm two liters of clean fresh 

 skim milk in a large pot at 37°C. 



(2) Add sufficient rennet to curdle. 



(3) Allow to settle for 10 minutes. 



(4) Break the curd into large pieces 

 by means of a stirring rod. 



(5) Heat to SO'^C. to contract the clot 

 and to express the whey. 



(6) Strain thru a cheese cloth. 



(7) Add 1.0%o peptone and 0.5%o NaCl. 



(8) Steam for 30 minutes. 



(9) Neutralize to tumeric paper. 



(10) Steam for one hour. 



(11) Dissolve 1.5% agar in (10). 



(12) Filter thru paper until clear. 



(13) Add 1.0%, Andrades indicator. 

 References: Committee A. P. H. A. (1909 



p. 287), Fulmer and Grimes (1923 p. 585), 

 Klimmer (1923 p. 172), Cunningham (1924 

 p. 102). 



1657. Huss' Whey Peptone Agar 



Constituents: 



1. Whey 1000.0 g 



2. Agar 20.0 g 



3. NaCl..... 5.0 g 



4. Peptone 1.0%, 10.0 g 



Preparation: (1) Dissolve 2, 3 and 4 in 1 



(The peptone may be omitted.) 

 Sterilization: Method not given. 

 Use: Cultivation of aroma producing bac- 

 teria. Bacillus esterificans, Maassen and 



