Description
Dextrose Tryptone Agar was developed by Williams in 1936 for the purpose of cultivating and calculating the numbers of thermophilic bacteria causing ‘flat sour’ spoilage of canned food. In later years various authorities recommended the use of this medium for the examination of food spoilage. These include:
Cameron and the Association of Official Agricultural Chemists.
Tanner in the examination of starch for thermophilic bacteria and sugar and canned food.
The American Public Health Association in the examination of sweetening agents used in frozen dairy foods.
The National Canners Association for the isolation and enumeration of organisms found in sugar and complex carbohydrates, cereals, dried fruits and vegetables and spices.
Baumgartner and Hersom in the examination of canned food of pH 4.5 and above for the presence of ‘flat sour’ thermophiles, mesophilic aerobes and facultative organisms.
Bromocresol purple must be carefully monitored in order to avoid the use of more inhibitory batches of the dye
