The presently disclosed subject matter relates to processes that comprise the vacuum extrusion of plant materials. In some embodiments, the plant materials are subjected to a change in pressure of −3 kPa or more. The vacuum extrusion can be used to break open the cell walls of the plant material and of any undesirable micro-organisms associated with the plant material. In some embodiments, the vacuum extrusion can be used as a step in a process for producing ethanol from plant materials, such as from sugar beets. In some embodiments, the vacuum extrusion can be used in a process for providing a desired plant cell-derived molecule, such as a sugar or starch.