Understanding how syrup viscosity shifts from the kettle to the depositor is key to producing consistent, high-quality gummies. The hot syrup begins in the kettle at a relatively low viscosity-it flows easily and is thin enough to mix thoroughly with flavors, colors, and active ingredients. As it moves toward the depositor, the syrup cools, and its viscosity increases significantly. This thickening is a natural result of the gelatin or pectin network beginning to set, and it’s carefully controlled to ensure the syrup remains pumpable and deposits cleanly into the molds.
This viscosity change directly affects both the weight and the shape of each gummy. Here’s how:
Impact on Weight
- Thinner syrup at the kettle means less resistance to flow, so depositing valves must be calibrated precisely. If the syrup is too thin, more can leak through before the valve closes, leading to overweight gummies.
- Thicker syrup near the depositor holds its shape better and is less likely to drip or form tails. However, if it becomes too viscous, it may not fill the mold cavity fully, resulting in underweight or incomplete gummies.
- Temperature control throughout the transfer is critical. 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 tends to level out quickly in the mold, filling every corner but also potentially forming a flat or spread-out shape rather than a sharp, defined gummy.
- Higher viscosity syrup at the depositor maintains a more rounded, robust form as it enters the mold-ideal for achieving consistent, attractive shapes. But if the syrup is too thick, it can cause “bridging” or incomplete filling of intricate mold details.
- The depositor’s nozzle design and timing must be adjusted to match the syrup’s viscosity profile. Slower deposit speeds or larger orifices are often needed as viscosity increases.
At KorNutra, we monitor and control these parameters closely. Our equipment and processes are optimized to keep the syrup viscosity within a narrow, consistent range from kettle to depositor. This ensures 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.