Malt Extract Broth

LAB 159

Description

A liquid medium of low pH for the growth of yeasts and moulds, typically employed as part of sterility testing protocols for various products. The high carbohydrate content of the medium ensures rapid growth of yeasts and moulds.

Method for reconstitution

Weigh 20g of powder and disperse in 1 litre of deionised water. Allow to soak for 10 minutes, swirl to dissolve and dispense into final containers. Sterilise by autoclaving at 115˚C for 10 minutes.

Appearance: Pale brown/straw, clear broth.

pH 5.4 + 0.2

Inoculation: Inoculate samples direct into tubes of broth according to the particular method being employed.

Incubation: 25˚C (or 37˚C) for up to 7 days aerobically, depending upon protocol used. Subculture turbid tubes onto solid media for identification of growth.

Candida albicans NCIMB 50010 Aspergillus niger NCIMB 50097

Storage of Prepared Medium: Plates - up to 7 days at 2-8˚C the dark.

Inoculation Method: Surface plating, streak out for single colon

Incubation: 37˚C for 48 hours aerobically.

References

American Public Health Association (1966). Recommended Meth for Microbiological Examination of Foods, 2nd Edn. (ed. J.M. Sh A.P.H.A. Washington.

Davis, J.G., (1959). Milk Testing 2nd edn, Dairy Industries, Lond