Tomato Juice Medium w/ Sterile Membrane filter

Principle And Interpretation

Field of Application: Beverages. DriFilter Membrane Nutrient Pad Medium is ready to use sterile culture media in the form of a 50 mm biological inert absorbent pads impregnated with Tomato Juice medium, then dried and sterilized in 55 mm petri plate. They eliminate the need of laborious media preparation and autoclaving procedures. The nutrient pads are to be just rewetted with sterile distilled water and are ready to use. Use of nutrient pads allows larger sample volumes to be tested at a time. Interpretation of results is directly by counting the CFUs and also quantifies the microbial load present in the sample. Mickle and Breed (1) first described the use of tomato juice in the culture media for Lactobacilli. Tomato Juice Medium is recommended for the cultivation of yeast and other aciduric organisms (2) and is based on the formula of Kulp and White for cultivation of yeasts and other aciduric microorganisms (3). Ability of tomato juice to enhance the recovery of Lactobacilli was observed by Kulp (4). Tomato juice acts as a source of carbon, nutrients and proteins. Yeast extract provides nitrogenous compounds and amino acids which stimulate the growth of spoilage strains (5). Low pH of the medium encourages growth of Lactobacilli while inhibiting the growth of accompanying bacteria. Phosphates buffer the medium. Magnesium sulphate, manganese sulphate and ferrous sulphate provide inorganic ions. Sodium chloride maintains osmotic balance in the medium. Field of Application: