In a gummy line, the energy intensity is set by the drying step, which dominates the total. Published work on soft-jellied candies puts a conventional stoving (drying) system at about 5.6 kWh per kg of product, and the same analysis found that high-efficiency stoves using desiccant dehumidifiers cut that to roughly 1.5 to 4 kWh per kg. Because drying can account for the majority of a line's energy, the full-line figure (mixing, cooking, depositing, drying, cooling, and packaging) runs above the drying number alone, typically several kWh per kg. Exact values vary with equipment, batch size, and formulation.
The step that dominates energy use is drying, often called conditioning or stoving in gummy manufacturing. Cooking the slurry and cooling the finished pieces contribute, but the drying step, whether in a stoving room or a conditioning tunnel, consumes the most energy per kilogram of output. Drying holds the product for hours in a heated, humidity-controlled chamber while moisture moves from the interior to the surface and is carried away. Cooking runs steam or direct heat over a short batch window, and cooling relies mostly on ambient air or fans, so both trail far behind drying.
Breakdown of Energy Use by Step
- Cooking: Heats the sugar and glucose syrup and hydrates the gelling agent. The temperature depends on the agent. Starch-based recipes cook to around 130°C for starch gelatinization. Pectin is heat-stable and sets at high temperature, so pectin masses are held near 90°C for depositing. Gelatin degrades under high heat, so it is added as a solution after the syrup has cooked. Steam is the usual heating medium.
- Drying: The dominant step. A 2015 case study of a confectionery plant found that heating and drying the candies consumed up to 84% of the factory's energy. Drying lowers moisture from roughly 20-25% down to about 16-21% in the finished piece, and starch-molded gummies can spend 24 to 72 hours in the drying room.
- Cooling: Uses ambient or chilled air to firm the pieces after drying. It is the smallest draw of the three, mostly fan power and, where chilled air is used, refrigeration compressors.
Why Drying Is the Dominant Energy Consumer
The drying stage holds air temperature and humidity steady inside the chamber for the whole cycle, commonly around 40-50°C for many gummy types. Removing moisture is endothermic: evaporating a kilogram of water takes roughly 2.3 MJ (about 0.64 kWh) of latent heat, and the dryer's fans and heaters add more on top. Drying times are long, so the equipment runs for extended periods and multiplies the total kWh. Cooking is a shorter batch step, and cooling uses less energy-intensive heat transfer, which is why neither competes with drying.
Reducing Drying Energy With Dehumidification
Open heated-air stoving pulls in large volumes of outside air, so a humid climate raises the energy needed to dry gummies. Conditioning rooms with desiccant dehumidification flip this: they strip moisture from recirculated air instead of reheating fresh air all day. In the soft-jellied candy analysis, a conventional stove ran about 5.6 kWh per kg, while desiccant-wheel systems brought it down to 1.5 to 4 kWh per kg and improved product quality. The humidity target matters for the gummy itself: jellies and gummies keep their shape and stay dry to the touch at roughly 30-40% relative humidity. For a brand comparing contract manufacturers, this is a unit-cost and capacity question, not just an environmental one. A line that dries in 24 hours instead of 72 triples throughput for the same floor space, and a lower kWh per kg shows up in the price per unit.
Each gummy line is unique. Line speed, gummy size, humidity control, and the energy source (electric versus gas) all shift the balance between steps. At KorNutra, the focus is on cutting energy intensity in the drying and conditioning step while holding texture and stability. Tighter control of chamber humidity and airflow shortens drying time and lowers the kWh per kg carried by a finished gummy.