Alternative long-term storage techniques use freezing or drying
to suspend cell metabolism, thus arresting cell functions and aging
(Benson, 2008). However, due to differences in cell structure and
the sensitivity of some microbial species to low temperatures
and desiccation, there are currently no published preservation
methods that can be applied for all microorganisms or whole
mixed microbial communities (Morgan et al., 2006). In addition,
research organisations range in levels of funding, staff availability
and expertise, and hence it is important to select methods to maintain
cultures that are cost and time effective, and that do not
require specialised skills (Belt, 1996)