An Improved Squash-Slide Freezer

Abstract

Liquid CO₂ is suited to more widespread use than the solid form, through its more extensive availability and much longer “shelf-life” in storage. Earlier models of devices for freezing squash-bearing slides used a chilled metal plate, but Bowen's design (Stain Techn., 31: 87-90, 1956) allowed the CO₂ to expand below and in direct contact with the slide. In the present model, the jet of CO₂ is directed downward within an insulated chamber which holds the slide. Advantages are: economy in the use of CO₂, facilitation in handling of slides, and quiet operation. CO₂ cylinders with built-in riser pipes are recommended for use in the vertical position.