Understanding the maximum shear rate before a gummy syrup’s gel structure breaks down is crucial for achieving consistent texture and quality. The answer depends on the specific formulation, but in our experience at KorNutra, the critical shear rate typically falls between 100 and 300 s⁻¹ for standard depositing operations. However, this is a general guideline; the exact threshold varies based on factors like gelatin bloom strength, solid content, and the presence of starches or pectins.
When the shear rate exceeds this range, the gel structure begins to degrade. This manifests as poor texture in several ways:
- Loss of Chewiness: The gummy becomes softer or more brittle than intended.
- Graininess or Grittiness: Sugar crystals or other ingredients may form unevenly, creating a sandy mouthfeel.
- Stickiness: The gel may become overly tacky, sticking to the mold or packaging.
- Syneresis: The syrup may weep liquid (water or oil) after setting, leading to an unappealing surface.
To pinpoint the exact maximum for your production, we recommend a two-step approach. First, you can conduct a rheological analysis of your specific gummy syrup to identify its yield stress and flow behavior. Second, check your depositing equipment-for instance, high-speed piston depositors or positive displacement pumps can generate shear rates over 500 s⁻¹, which may be too aggressive for tender gels. At KorNutra, we fine-tune depositing parameters like nozzle size, flow rate, and temperature to keep shear rates below 200 s⁻¹, ensuring a stable gel structure and excellent texture.