Thermo Scientific Limited has extended the Thermo Scientific range of culture media to include Andrade Peptone Water (CM0061), a nutrient base containing Andrade's indicator which can be used for the biochemical identification of micro-organisms based on the catabolism of added carbohydrates and other organic compounds.

Andrade's indicator is colourless, or very slightly pink, at pH 7.4 but will turn bright pink in acid conditions or yellow in alkaline conditions over a pH range of 5 to 8. A variety of filter sterilised carbohydrate compounds can be added to separate tubes of the base medium post-sterilisation and biochemical identification is made according to the organism's ability to utilise these compounds. Fermentation is indicated by the production of acid and gas (which is collected in a small inverted fermentation tube).

The peptone content of Thermo Scientific Andrade Peptone Water is free from any fermentable carbohydrate and nitrates that may interfere with gas production, thus ensuring accurate and reliable identifications. The medium is supplied in dehydrated format, which gives it a long shelf life, and is easily prepared in distilled water.