Nutrient Agar w/ Manganese

Nutrient Agar w/ Manganese is recommended for promoting sporulation in Bacillus species. This medium is conventionally abbreviated as NAMn favours culture and sporulation of aerobic Bacillus species especially from canned foods. It has been reported that organisms recovered from spoilage of foods such as fruit drinks, tomatoes, acidified onions and other canned foods sporulate well aerobically on this media. Thermophilic bacteria such as B. stearothermophillus are capable of growth at 55-65°C while an incubation temperature of 30 to 35°C is favorable for culture and sporulation of mesophilic spore formers . This property is exploited to grow and therefore differentiate mesophilic and thermophilic spoilage bacteria. As recommended by APHA, in routine diagnosis for spoilage in canned foods, microbiological cultural procedures involve the use of primary recovery media and subculture media to identify spoilage bacteria and study its growth characteristics.