In 1890, M¨uller-Thurgau from Geisenheim introduced the concept of inoculating wine fermentations with pure yeast starter cultures (Pretorius, 2000). Currently, yeast manufacturing companies market a wide variety of dehydrated cultures of various S. cerevisiae strains. Most commercial freeze-dried cultures (or active dry yeast, ADY) contain yeast that was originally selected by various manufacturers from successful natural fermentations. In large-scale wine production, however, where rapid and reliable fermentations are essential for consistent wine flavor and predictable quality, the use of selected pure yeast inocula of known ability is preferred. These large wineries will be the main beneficiaries of programs aimed at producing new yeast strains with even more reliable performance, reducing processing inputs and facilitating the production of affordable high quality wines. The brewer or winemaker now has the option of selecting a commercial strain for a specific attribute (for example, the ability to hydrolyze monoterpenes from glycolysated precursors). There is a strong incentive to develop wine yeast strains with an ability to accumulate trehalose and glycogen as starter cultures, because trehalose appears to stabilize cell membranes of lyophilized yeast, as well as theircellular proteins by replacing water and forming a hydration shell around proteins. Glycerol accumulation seems to control the concentration of solutes inside the cell relative to that of the culture medium, thereby counteracting the negative effects of dehydration.