The viscosity of hot syrup shifts as it moves from the kettle to the depositor, and that shift directly shapes the final gummy. The syrup starts thin in the kettle—easy to mix with flavors, colors, and active ingredients. As it cools on the way to the depositor, it thickens. The gelatin or pectin network begins to set. It's a delicate balance: the syrup needs to stay pumpable and deposit cleanly into molds.
This viscosity change hits both weight and shape. Here's what happens.
Impact on Weight
- Thin syrup at the kettle flows easier, so depositing valves must be calibrated carefully. Thin syrup leaks past the valve before it closes, causing overweight gummies.
- Thicker syrup near the depositor holds its shape better and won't drip or form tails. But if it gets too thick, it might not fill the mold cavity fully, leaving you with underweight or incomplete gummies.
- Temperature control matters a lot. Even a 5°F drop in syrup temperature can increase viscosity by 20-30%, causing measurable weight variation from the start to the end of a depositing run.
Impact on Shape
- Low viscosity syrup levels out fast in the mold. It fills every corner but can flatten into a spread-out shape rather than a sharp, defined gummy.
- Higher viscosity syrup at the depositor holds a rounder, more robust form as it enters the mold—great for consistent, attractive shapes. But if it's too thick, you get “bridging” or incomplete filling of intricate mold details.
- The depositor’s nozzle design and timing need to match the syrup’s viscosity profile. Slower deposit speeds or larger orifices often work better as viscosity climbs.
That's why we at KorNutra monitor and control these parameters closely. Our equipment and processes keep syrup viscosity within a narrow, consistent range from kettle to depositor. Every gummy comes out with the intended weight and shape, run after run. Proper viscosity management is one of many factors that separate a reliable manufacturing partner from one that struggles with variation.