General characteristics of lactic acid cultures

Lactic acid cultures are often called starters or referred to by the acronym 'LAB' which stands for lactic acid bacteria. The following lists identify and briefly describe some properties of LAB. LAB are:

  • Non-motile gram+ bacteria
  • Non spore forming
  • Catalase and nitrate negative
  • Micro-aerophilic which means they tolerate only low oxygen concentrations
  • Not psychrotrophic which means that cold storage rapidly depletes their numbers and encourages the growth of spoilage bacteria as described in Raw milk quality.
  • Cocci (spherical cells) 1 µm in diameter OR rods (rod shaped cells) 1 µm wide and 2 to 3 µm long.