The transformation of aerated confectionery from elastic gelatin-sucrose hydrocolloid matrices into stable, shatter-crisp structural forms represents one of the most demanding engineering applications of vacuum sublimation freeze-drying (lyophilization). Traditional marshmallows embody an unstable equilibrium consisting of a supersaturated sucrose-glucose syrup stabilized by a whipped gelatin network containing roughly 15% to 18% free water. When subjected to standard heat dehydration, this foam matrix collapses instantaneously into a dense, gummy caramel due to glass transition phase changes ($T_g$) falling well below operative thermal evaporation points.
Our Zhangzhou manufacturing complex bypasses thermal collapse via a cryogenic deep-freezing protocol executed at temperatures between -38°C and -45°C. At these extreme cryogenic thresholds, the unbound water content in our miniature, extruded, or molded marshmallow formulations flash-freezes into microcrystalline ice arrays without fracturing the delicate protein foam boundaries. During the subsequent primary drying phase inside our 8,000 m² vacuum chamber infrastructure, ambient pressure is driven down to 0.05–0.1 mbar. Controlled radiant plate heat supplies the latent heat of sublimation (approximately 2.8 MJ/kg), converting internal ice lattices straight into water vapor without crossing the liquid phase.
The outcome is an ultra-porous, rigid cellular scaffold exhibiting a final residual water activity ($a_w$) under 0.20 and absolute residual moisture levels below 2.5%. For industrial food process engineers and artisan chocolatiers in Charleroi, this state of vitrification offers transformative physical stability: the freeze-dried marshmallow does not undergo plastic deformation under mechanical cutting, provides an exceptionally snappy mouthfeel, and retains immediate rehydration kinetics when suspended in hot fluid systems.