Propagation
Propagation is a stepwise, aerobic process where the brewing strain of choice is removed from storage to be grown such
that sufficient cell numbers, free of contaminants and of the desired physiological condition, are obtained to adequately
inoculate (pitch) the zero-generation fermentations (Voigt & Walla, 1995). Culture maintenance methodologies have
also evolved over time considering the initial exclusive use of agar slants that developed into alternative methods of
storage in liquid nitrogen at 196 1C (Wellman & Stewart, 1973) and cryovials at 70 1C (Hulse et al., 2000). The use
of storage methodology depends on sample integrity preservation, ease of use and transport implications.