The "Pyler says" series explores excerpts from Baking Science & Technology, a textbook that teaches readers a range of baking and equipment concepts. The following passage is from Chapter 11: Finishing and Packaging.

When slicing problems occur or when replacing blades, always save the used blade for inspection. By examining the blade carefully, the bakery engineer may find evidence that some other component on the slicer is the source of the problem. For example, damage on the non-slicing edge is a sign of backing roller wear, and sheared scallop points indicates worn blade guides or that the blade is cutting into something very hard.

Saving the blade lets its manufacturer identify whether the blade was sub-standard before it was installed. If the package in which the blades were shipped is available, the blade manufacturer can glean more information concerning the exact production of the blades. The packaging information should always be kept on hand until a new set of blades has been installed. The packaging and the blade samples allow the manufacturer to identify problems within their own manufacturing process and to analyze the metallurgical properties of the blade. The long-term result of such actions is that bakers get improved blades compared with the first blade that was ever bought.

The next step is to inspect the machine where the blade was installed. Look for any abnormalities that could have damaged the blade such as worn or loose parts. If blades are installed, check their tension and calibration of the tension gauge.

Other indicators can also help find problems before it affects production. Should any of the following problems occur, take time to do a thorough analysis of the slicer as soon as production can accommodate the inspection.

Bread crumb texture

How the slice looks can be a good indicator that something is not right. Crumb consists of two types: (a) the darker, dry particles that come from the crust of the product and (b) the fairer, moist particles from the interior of the bread loaf. Dark crumb is seen before and after the slicing unit, and light crumb appears only after the slicing unit. A high volume of light crumb means that something needs to be corrected. The first places to check are the blade tensioning and hone stone positioning.

Slice thickness

If sliced products show both thick and thin slices in the same loaf, something is wrong. In this case, look at blade tensioning, lattice rigidity and blade guides to find which is not properly supporting the blades.

Blade wear

If blades experience accelerated wear, the tension may be too high. Also, blade guides may have worn out, or a honing stone is out of position. Look for anything that may be damaging the blade edge. Any other component that shows accelerated wear is also an indicator that something is not right inside the unit.

Blade tension

Incorrect blade tension is the main reason blades do not operate correctly, and improper tensioning affects, directly or indirectly, many other components of the slicing unit. Make sure that operators and maintenance personnel set up and operate the slicer’s blades at the manufacturers recommended tension. (Cox 2007)

Cox, P. 2007. Slicer Maintenance and Instruction. Hansaloy: Davenport, Iowa.