CRITERION™ STANDARD METHODS AGAR

Cat. no. C6980 CRITERION™ Standard Methods Agar 38.0gm
Cat. no. C6981 CRITERION™ Standard Methods Agar 500gm
Cat. no. C6982 CRITERION™ Standard Methods Agar 2kg
Cat. no. C6983 CRITERION™ Standard Methods Agar 10kg
Cat. no. C6984 CRITERION™ Standard Methods Agar 50kg

INTENDED USE

Hardy Diagnostics CRITERION™ Standard Methods Agar is recommended for use in determining the microbial content in dairy products, food, water samples, and other material of sanitary importance.

This dehydrated culture medium is a raw material intended to be used in the making of prepared media products, which will require further processing, additional ingredients, or supplements.

SUMMARY

Standard Methods Agar is a modified formulation of Tryptone Glucose Skim Milk Agar that was developed by Bowers and Hucker.(5) Yale showed that this modified version is more effective in plate count procedures on milk and dairy products.

CRITERION™ Standard Methods Agar is equivalent to the formulation of Plate Count Agar (Tryptone Glucose Yeast Agar) as listed in Standard Methods for the Examination of Water and Wastewater, 18th ed., AOAC, and USP.(1-4) The American Public Health Association (APHA) recommends use of the medium for performing the "standard plate count" on dairy products.(6)

Bacterial growth nutrients are provided by peptone, yeast extract, and glucose. B-complex vitamins are primarily supplied by yeast extracts. Glucose serves as an energy source. These nutrients, together with the nutrient factors present in the dairy products to be evaluated will support the growth of the majority of organisms found in the dairy samples.

FORMULA*

Gram weight per liter: 23.5gm/L
Pancreatic Digest of Casein 5.0gm
Yeast Extract 2.5gm
Glucose 1.0gm
Agar 15.0gm

Final pH 7.0 +/- 0.2 at 25ºC.

* Adjusted and/or supplemented as required to meet performance criteria.

STORAGE AND SHELF LIFE

Store the sealed bottle(s) containing dehydrated culture medium at 2-30ºC. Dehydrated culture medium is very hygroscopic. Keep lid tightly sealed. Protect dehydrated culture media from moisture and light. The dehydrated culture media should be discarded if it is not free-flowing or if the color has changed from its original light beige.

Store the prepared plated media at 2-8ºC. Store the prepared tubed and/or bottled media at 2-30ºC.

PRECAUTIONS

METHOD OF PREPARATION FOR DEHYDRATED CULTURE MEDIA

1. Suspend 19.0gm of the dehydrated culture media in 1 liter of distilled or deionized water.

2. Heat to boiling and mix to dissolve completely.

3. Sterilize in the autoclave at 121ºC. for 15 minutes.

PROCEDURE AND INTERPRETATION OF RESULTS

For information on procedures and interpretation of results, consult listed references or refer to the prepared media Instructions for Use (IFU) for Cat. No. G43.

LIMITATIONS

MATERIALS REQUIRED BUT NOT PROVIDED

Standard microbiological supplies and equipment such as autoclaves, incinerators, and incubators, etc., are not provided.

QUALITY CONTROL

Test Organisms Inoculation Method* Incubation Results
Time Temperature Atmosphere
Staphylococcus epidermidis
ATCC ® 12228
A 24hr 35°C Aerobic Growth
Escherichia coli
ATCC ® 25922
A 24hr 35°C Aerobic Growth
Enterococcus faecalis
ATCC ® 29212
A 24hr 35°C Aerobic Growth

User Quality Control

PHYSICAL APPEARANCE

CRITERION™ Standard Methods Agar powder should appear homogeneous, free-flowing, and light beige in color. The prepared media should appear slightly opalescent, and light amber in color.

REFERENCES

1. American Public Health Association. Standard Methods for the Examination of Water and Wastewater, APHA, Washington, D.C.

2. Association of Official Agricultural Chemists. 10th ed. p. 737; 1965.

3. Association of Official Analytical Chemists. Official Methods of Analysissm, AOAC, Washington, D.C.

4. The Official Compendia of Standards. 2008. USP27-NF22. United States Pharmacopeial Convention, Rockville, MD.

5. Bowers and Hucker. 1944. Tech. Bull.; p. 228. N.Y. State Exp. Station.

6. American Public Health Association. Standard Methods for the Examination of Dairy Products, APHA, Washington, D.C.

7. APHA Technical Committee on Microbiological Methods for Foods. Compendium of Methods for the Microbiological Examination of Foods, APHA, Washington, D.C.

8. U.S. Food and Drug Administration. Bacteriological Analytical Manual. AOAC, Arlington, VA.
http://www.fda.gov/Food/FoodScienceResearch/LaboratoryMethods/ucm2006949.htm.

ATCC is a registered trademark of the American Type Culture Collection.

062116gr