The transformation of liquid syrup into a chewy solid is driven by two structural processes: hydrocolloid gelation and controlled water removal. At KorNutra, we engineer both to create consistent, shelf-stable gummy supplements every time.
Core Chemical Reactions: The Irreducible Steps
The following steps are structural. Without them, syrup stays syrup.
- Concentration and Water Evaporation: The syrup is a mix of sucrose, corn syrup (glucose syrup), water, and the gelling agent. It is cooked to a target soluble-solids content of roughly 78 to 82 °Brix, depending on the gelling system, which boils off excess water and concentrates the sugars. Too little water removed leaves a soft, sticky piece; too much makes it dry and tough.
- Gelatin or Pectin Gelation: Gelatin or pectin is hydrated and mixed into the hot syrup, then the mass cools and, for pectin, reaches the right pH and solids level. The hydrocolloid forms a three-dimensional gel network that traps water and sweeteners, giving the piece its elasticity and melt-in-mouth chew. This is the step that turns a liquid into a solid; without the gel network, the cooled mass would be a thick syrup or paste, not a chewy solid.
- Setting and Moisture Removal: After depositing into starch molds, the pieces move to drying rooms, a step the industry calls stoving or curing. The starch mold absorbs surface water while the gel sets. Gelatin gummies can set at room temperature within about 24 hours; starch-molded jellies are commonly dried for 24 to 72 hours to a final moisture of roughly 14 to 20 percent. This dehydration is structural: it firms the piece and lowers water activity to the range where the gummy stays shelf-stable. A piece pulled from the molds early is soft, wet, and prone to sticking.
One step that does not belong on this list is sugar crystallization. Gummies are non-crystalline confections, and formulators deliberately suppress crystallization by using more corn syrup than sucrose; crystallized sugar would make the piece grainy and opaque. Seeding with sugar crystals is a technique for crystalline sugar candies such as fudge and fondant, not for gummies.
These three steps are irreducible because each directly determines whether the finished piece is a stable, chewy solid or a runny, sticky mass. Deviations in temperature, soluble solids, pH, or time cause failures: under-concentration, incomplete gelation, and residual moisture all show up as defects in the finished gummy.
Cosmetic vs. Structural Process Steps
Other stages in gummy manufacture affect appearance, mouthfeel, or handling, but they do not form the chew itself:
- Coloring and Flavoring Addition: Colors and flavors are added near the end, after the syrup reaches the right concentration. They do not form the gel network, so an uncolored, unflavored gummy is still a chewy solid. Acidulants are a separate matter, since pH helps pectin set, but color and flavor themselves are cosmetic.
- Surface Oil Coating: A thin layer of vegetable oil or wax, applied after demolding, keeps pieces from sticking together and adds gloss. The structure exists without it.
- Polishing and Dusting: Tumbling with starch or confectioner's sugar removes surface tack and gives a matte or sanded finish. This is a surface treatment, not a structural requirement.
Water Activity and Shelf Life
Drying matters for more than firmness. A gummy's water activity (aw) measures the water that is free enough to support microbial growth, and that number, rather than moisture content alone, is what decides whether the piece stays clean on the shelf. Molds and yeasts generally stop growing below a water activity of about 0.60, and gummies are commonly finished to a water activity in the 0.55 to 0.70 band. That is why a gummy can sit at room temperature for months without refrigeration, and why under-drying is a defect rather than a style choice. For a brand, this is a spec to pin down with your manufacturer: moisture content alone does not tell you the water activity, because humectants such as glucose syrup and sugar alcohols hold water while keeping less of it available to microbes.
At KorNutra, we focus our R&D on the structural chemistry, meaning concentration, gelation, and moisture control, while keeping the cosmetic steps flexible to match brand preferences. The result is a chewy solid that is consistent, shelf-stable, and free of unnecessary complexity.