CRITERION™ LACTOSE BROTH

Cat. no. C5940 CRITERION™ Lactose Broth 26gm
Cat. no. C5941 CRITERION™ Lactose Broth 500gm
Cat. no. C5942 CRITERION™ Lactose Broth 2kg
Cat. no. C5943 CRITERION™ Lactose Broth 10kg
Cat. no. C5944 CRITERION™ Lactose Broth 50kg

INTENDED USE

Hardy Diagnostics CRITERION™ Lactose Broth is used to detect coliforms in food, dairy products, and water, and to preenrich samples for the recovery of Salmonella species.

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

In processed foods, Salmonella species can be present in low concentrations and in debilitated condition. Lactose Broth provides a environment favorable for the recovery of Salmonella. The media provides for the repair of cell damage, dilutes toxic substances that may be present, and favors growth of Salmonella over other species.(2)

Lactose Broth is also used to detect coliforms in food, dairy products, and water. The concentration of ingredients in Lactose Broth, when used to detect coliforms in samples, must remain the same after addition of the sample being tested.

FORMULA

Gram weight per liter: 13.0gm/L
Pancreatic Digest of Gelatin 5.0gm
Lactose 5.0gm
Beef Extract 3.0gm

Final pH 6.9 +/- 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 culture media at 2-8ºC.

PRECAUTIONS

METHOD OF PREPARATION FOR DEHYDRATED CULTURE MEDIA

1. See chart below for amount of the dehydrated culture media to suspend in 1 liter of distilled or deionized water.

Lactose Broth Preparation:(4,7)

Inoculum (ml) Amount of Medium in Tube (ml) Amount of Medium and Inoculum (ml) Dehydrated Lactose Broth (grams/liter)
1 10 or > 11 or > 13.0
10 10 20 26.0
10 20 30 19.5
100 50 150 39.0
100 35 135 49.4
100 20 120 78.0

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. K137.

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
Escherichia coli
ATCC ® 25922
A 18-48hr 35°C Aerobic Growth; gas production
Salmonella enterica subsp. enterica serovar typhimurium
ATCC ® 14028
A 18-48hr 35°C Aerobic Growth; no gas production

User Quality Control

PHYSICAL APPEARANCE

CRITERION™ Lactose Broth powder should appear homogeneous, free-flowing, and light beige in color. The prepared media should appear clear, and light to medium amber in color.

REFERENCES

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

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

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

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

5. U.S. Pharmacopeia, 22nd rev. 1990. U.S. Pharmacopeial Convention, Rockville, MD.

6. Jorgensen., et al. Manual of Clinical Microbiology, American Society for Microbiology, Washington, D.C.

7. MacFaddin, J.F. 1985. Media for Isolation, Cultivation, Identification, Maintenance of Bacteria, Vol. I. Williams & Wilkins, Baltimore, MD.

8. Quality Assurance for Commercially Prepared Microbiological Culture Media, M22. Clinical and Laboratory Standards Institute (CLSI - formerly NCCLS), Wayne, PA.


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

053116gr