FAM STUMABO Introduces StoneExtractor to Reduce Stone Damage in Potato Chips Cutting

As processors increasingly work with potatoes sourced from more challenging growing conditions, FAM STUMABO has introduced StoneExtractor to improve stone evacuation within the cutting head and reduce the operational impact of embedded stones. The solution delivered strong results under industrial processing conditions at Kelly Ges.m.b.H., a potato chips producer in Austria.

In potato chips processing, small stones and foreign materials continue to present operational challenges. Even after multiple washing and sorting stages, embedded stones can still reach the slicing process hidden inside potatoes and remain difficult to detect or remove.

According to FAM STUMABO, changing weather conditions, harvesting constraints and supply pressures are forcing processors to work with potatoes grown in less ideal and rockier soils, increasing the likelihood of stones reaching the cutting stage.
 

Small stones can create major operational costs

Despite the use of optical sorting systems and cleaning technologies, a small percentage of foreign materials can still enter the cutting head. Once inside, even small stones may cause significant blade damage, increase maintenance requirements and contribute to unplanned downtime.

Stones that are not immediately evacuated may continue moving inside the cutting head and strike multiple blades, causing cumulative damage and affecting slice consistency.

FAM STUMABO highlighted a recent project with a European potato chips producer that experienced recurring stone-related problems after sourcing potatoes grown in rockier soils.
 

StoneExtractor focuses on stone evacuation

To address this issue, FAM STUMABO developed StoneExtractor, a new cutting head segment design intended to improve the evacuation of small stones from the cutting zone.

Rather than focusing only on impact resistance or detection, the solution is designed to prevent stones from remaining inside the cutting head after impact, helping reduce repeated blade strikes and cumulative damage.

The StoneExtractor is implemented through an upgraded segment geometry and can be integrated into existing equipment without major modifications.
 

A broader "3S" system approach

The StoneExtractor forms part of FAM STUMABO’s broader "3S" approach to foreign material management in potato slicing applications: Shielding, Sensing and Separation.

The StoneDefender technology focuses on shielding by redirecting impacts away from critical components, while Scalibur™ provides sensing capabilities by detecting abnormal resistance and stopping the cutting process before severe damage occurs.

FAM STUMABO’s StoneExtractor segment design features optimized grooves and evacuation openings to reduce cumulative blade damage

StoneExtractor completes the system through separation, enabling efficient evacuation of small stones from the cutting head during operation.
 

Validated under industrial processing conditions

According to FAM STUMABO, trials under industrial processing conditions demonstrated reduced cumulative blade damage, lower maintenance requirements, improved process stability and more consistent slice quality.

Jörg Plumanns, Industry Manager Potato Chips at FAM STUMABO:

"The key advantage is that stones are removed at the point where the impact occurs. If they exit immediately, they cannot continue circulating and damaging other blades."

Jörg Plumanns, Industry Manager Potato Chips at FAM STUMABO, with centrifugal cutting technology used in potato chips processing