Application · Food & Plant Protein
Puffed Snack Extrusion: 100–500 kg/h
Food extrusion shares the barrel with plastics but not the rules: the machine is a cooker, and the product is defined by moisture, SME and die pressure rather than by melt temperature alone. A reference puffed snack extrusion page from Kerke.
Quick answer
Puffed snack and cereal lines use a food-grade twin screw with L/D 20–32, steam or water injection and a die-face cutter, at 100–1,000 kg/h. We have delivered and commissioned food extrusion lines, including a project with a Thai food-engineering department.
Workshop photos and a running video — shot on our own lines, not stock images.
What sets the limit
Flour blends are preconditioned, fed into the extruder, cooked by mechanical energy plus injected water/steam, and cut at the die face. Drying and coating follow downstream.
| Parameter | Value / range |
|---|---|
| Products | Puffed snacks, breakfast cereal, nutritional powder |
| L/D | 20–32 (food configuration) |
| Injection | Water / steam / oil |
| Cutting | Die-face cutter with variable speed |
| Output (reference) | 100–1,000 kg/h |
| Model | KTE-36B, KTE-50B, food-grade build |
Output figures are measured on the reference material stated above. Filler grade, bulk density and moisture move output by ±15% — that is why every quotation we issue is tied to a trial report.
Process flow, step by step
- FeedingLoss-in-weight dosing of polymer and filler; side feeder or liquid injection where the formulation needs it.
- Melting and dispersingScrew geometry with 45°/90° kneading blocks; barrel profile set by the polymer.
- DevolatilizationVacuum vent at −0.06 to −0.09 MPa removes moisture and volatiles before the die.
- Pressure build-upThrottle or discharge section stabilises die pressure; a melt pump where gauge control matters.
- Pelletizing and packingDie-face cutter with variable speed; then centrifugal dryer, vibrating screen and bagging.
Equipment configuration
| Stage | Equipment | Why this choice |
|---|---|---|
| Main machine | Lab Equipment & Send-Your-Material Trials | Architecture follows the filling level and the mixing duty, not the required tonnage. |
| Screw geometry | Building-block elements, W6Mo5Cr4V2, bimetallic liner | Wear package for abrasive filler; mixing blocks only where dispersion demands them. |
| Feeding | Loss-in-weight feeder, side feeder where needed | Recipe accuracy: ±0.5% short term on the weighed component. |
| Pelletizing | Pelletizing system | Chosen by polymer and filler ceiling — water contact is the deciding column. |
| Downstream | Centrifugal dryer, vibrating screen, bagging | Fines below 2% and moisture below the specification of your downstream process. |
Output by model
| Model | Screw dia. (mm) | Speed (rpm) | Motor (kW) | Torque (N·m) | Output (kg/h) |
|---|---|---|---|---|---|
| KTE-20B | 21.7 | 500 | 4 | 2×30 | 2–15 |
| KTE-25D | 26 | 500 | 7.5–11 | 2×85 | 5–20 |
| KTE-36B | 35.6 | 500–600 | 18.5–22 | 2×210 | 20–100 |
| KTE-36D | 35.6 | 500–600 | 22–37 | 2×352 | 20–150 |
Three mistakes that cost the most
1. Using a plastics build for food: dead corners in the barrel and non-food-grade seals fail
Using a plastics build for food: dead corners in the barrel and non-food-grade seals fail hygiene audit.
2. Recipe and screw profile are product-specific; a generic screw gives inconsistent expansio
Recipe and screw profile are product-specific; a generic screw gives inconsistent expansion.
3. Raw material moisture left uncontrolled
Raw material moisture left uncontrolled — expansion ratio follows input moisture, and without a spec the same recipe gives a different crunch every shift.
FAQ
Is the machine food-grade certified?
The food configuration uses 304/316 contact parts and food-grade seals; certification for your market (CE, FDA) is documented per project.
Can we test our recipe?
Yes — send 20–50 kg of flour blend; we run trials on the lab extruder and return samples with process parameters.
What output can you guarantee for this application?
The reference band is 100–1,000 kg/h, measured on the stated material. We quote a guaranteed figure only after a trial on your own material, because filler grade, bulk density and moisture move output by ±15%.
Can we run our material before ordering?
Yes — send 25–50 kg. We return pellets, a running video and a report with temperatures, screw speed, feeder settings and output per hour. The trial is free; you cover the freight.
What is the delivery time?
30–45 working days for standard configurations, 45–70 for custom screw geometry and ODM work. Voltage and frequency are built for the destination country.
Where these numbers come from
Parameters are taken from the Kerke product parameter table and the product master data sheet, and cross-checked against commissioning records for lines in the same application. Formulations and temperature windows are typical industry values, not a recommendation for your specific compound — every figure marked reference must be confirmed on a material trial before it becomes a contractual number.
Reviewed by the Kerke process team, Nanjing. Page updated 6 November 2026.
Send 25–50 kg and we run it on our lab extruder: pellets, running video and a capacity report back in 3–7 days.
Puffed snack extrusion — the short version
Note on puffed snack extrusion: the numbers above are reference ranges from Kerke's own trial runs, not catalogue promises. Screw geometry, wear package and pelletizing method are set on the trial bench first, so the output you compare is the output you get. If your grade is not in the tables, send it — the closest configuration is usually a change of screw set, not a different machine.
Related on this site: Machine range: KTE-50B to 135D · Pelletizing methods compared · quotation and free trial · Wikipedia: Masterbatch






