Assessment of knife sharpness by means of a cutting force measuring system.

Following a brief description of the problem of musculoskeletal disorders (MSDs) in the meat industry and use of knives, this paper presents a study of the influence of the main intrinsic technical characteristics of a knife on its cutting performance. This study prompted design of a specific system for measuring initial cutting capacity and cutting edge retention. This design process preceded research into test conditions (cutting speed, sample nature and thickness, knife inclination angle, etc.) offering optimum test bench operation. This equipment was then used to study the influence of blade inclination angle, steel grade and sharpening angle on cutting performance. It has been shown that cutting force varies with blade inclination. Use of knives with curved blades and/or a blade inclined with respect to the knife handle is therefore preferred in relation to our cutting force reduction objective. It has also been shown that choices are in fact governed by compromises in relation to other parameters (steel grade and edge angle). These observations confirm the need to set up suitable training of knife users to achieve best possible cutting performance.