Wrapper Tearing: What to Do When the Outer Dough Breaks

Wrapper tearing is the most common complaint in encrusting production. A few torn pieces in a tray means the whole tray has to be sorted or remade, and with frozen products, they fall apart in the customer's pot. Fortunately, most causes of tearing leave clues, and if you check in the right order, you can usually find the answer.

Why Does the Wrapper Tear?

Encrusting works by stretching the outer dough open, wrapping it around the filling, and then cutting and closing it. The outer dough is stretched during this process, so anything that keeps it from "stretching open" or that "punctures" it will cause tearing:

• Dough too firm: Not enough extensibility, so it cracks as soon as it's stretched.
• Dough too soft and sticky: Not strong enough, so it bursts when pushed by the filling, or sticks to the mechanism and gets pulled apart.
• Insufficient resting: The gluten is still tight with strong spring-back, so it cracks easily when stretched.
• Surface drying and skinning: The dried layer has no elasticity, and when it's rolled in, it becomes a tear.
• Over-proofing: The gluten is stretched to its limit. See Running Fermented Dough on Machines.
• Filling issues: Particles that are too large or hard, or sharp bones or stems, can pierce the wrapper; a watery filling soaks and softens it.
• Wrapper-to-filling ratio: Too much filling and too little wrapper stretches the wrapper to its limit.

Is It the Dough or the Machine?

A practical way to tell: if the machine settings haven't changed and it ran fine yesterday but tears today, the ingredients have most likely changed, for example a new batch of flour, hotter weather, or a wetter filling. If the ingredients haven't changed and tearing suddenly appears in a fixed spot, for instance every piece cracks on the same side, then it's more likely a machine-side issue, such as residue stuck on a contact surface, or wear or looseness somewhere.

So we recommend checking ingredients first, then the machine:

1. Switch to a batch of dough and filling you know is good and test again to see if it still tears.
2. Check dough temperature, firmness, and whether the surface has a dry skin. See Wrapper Moisture Content and Dough Temperature and Resting Time.
3. Check filling particle size and moisture. See Filling Viscosity, Particle Size, and Moisture.

How to Adjust

Ingredient side: Adjust water so the dough is moderately firm, extend resting time, and cover the dough to prevent drying; cut the filling finer, remove tough stems and bone fragments, and deal with water release.

Settings side: Following the machine's operating manual, moderately reduce the filling ratio or increase the wrapper amount, and adjust the speed. Change only one thing at a time and watch a few dozen pieces before deciding.

Machine side (check after stopping):

Before checking anything by hand, press stop, turn off the power, and unplug the machine or cut the main switch, and make sure the machine has come to a complete stop. In factories with multiple workers, lock the switch and hang a "Under maintenance, do not energize" tag. Article 57 of Taiwan's Occupational Safety and Health Facilities Rules (職業安全衛生設施規則) requires that when machinery is being cleaned, oiled, inspected, repaired, or adjusted, operation and feeding must be stopped, and measures such as locking out and posting signs must be taken to prevent accidental start-up.

Once the power is confirmed off, you can perform these self-checks:

• Following the operating manual, remove the detachable contact parts and check whether dried dough or filling residue is stuck at the outlet or the cutting point.
• After cleaning, make sure the parts are reinstalled in their original positions, not backwards or loose.
• Visually check contact surfaces for obvious scratches, burrs, or deformation.

If you see parts that are deformed, chipped, or worn, or the ingredients are normal and the wrapper still tears in a fixed spot after cleaning, don't continue disassembling or adjusting it yourself.

When to Call for Service

The science behind tearing has to do with the viscoelasticity of the materials. The discipline on which RHEON founder Torahiko Hayashi based his development of the encrusting machine was rheology, and the match between the mechanism and the dough's properties is very delicate. Adjustments beyond the scope of the operating manual are safer left to professionals, and won't get messier the more you adjust.

FAQ

Q: Why does the wrapper keep tearing during encrusting?
A: Most commonly the dough is too firm or too soft, under-rested, or has a dried surface, or the filling is too coarse, too hard, or watery; it can also be too much filling in the wrapper-to-filling ratio.

Q: How can I tell whether it's the dough or the machine?
A: Test with a batch of ingredients you know is good. If it doesn't tear, it's the ingredients; if good ingredients still tear in a fixed spot, it may be the machine.

Q: Can I adjust the machine myself to stop tearing?
A: Settings permitted by the operating manual, such as the wrapper-to-filling ratio and speed, you can adjust yourself; don't touch anything that involves disassembling internal mechanisms.

Q: What if it still keeps tearing after cleaning?
A: Stop the machine, cut the power, note what happens and the machine model, and contact the manufacturer or a service provider for inspection. Dong-Yih Machinery specializes in manufacturing automatic food encrusting and forming machines. Please call us at 06-257-4644 to ask.