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The viscoelastic properties of foods determine deformation, fracture and friction during industrial cutting applications and substantially affect the cutting behavior, especially at high cutting velocity. Using a custom-built high-speed test station the cutting behavior of representative foods (either based on a protein network, plant tissues and sugar based confectionary) and food models on elastomer basis was investigated at a cutting velocity ranging from 10 −4  m/s up to 10 m/s. On the basis of cutting force data and dynamic mechanical analysis performed between 1 rad/s and 10 0  rad/s, the cutting behavior of the systems was investigated. In general, the cutting force profiles depended on cutting velocity and could be related to deformation characteristics that were measured in dynamic mechanical analysis (except for plant tissue whose inherent composite structures seem to contribute to brittle behavior at each cutting velocity). Sugar based confectionary showed a strong rate dependence with brittle fracture and splintering in the high-speed region. For all systems except plant tissues a velocity dependent deformation cutting parameter, derived from the initial cutting forces, coincides with the power law frequency dependence of the complex modulus. This relation was used to build a model approach with which the pre-crack cutting forces at high-speed cutting velocity can be predicted with commercially available standard testing machines. [ABSTRACT FROM AUTHOR]

Because of the viscoelastic and therefore time-dependent properties of many foods, cutting at high velocity is a complicated process that may lead to undesired fracture and deformation and, thereby, reduce cutting quality. In addition, the analysis of the process is difficult because of the limited availability of commercial equipment for high-speed testing. This work reports on the development of a test station for high-speed cutting that enables a cutting velocity of up to 10 m/s; process analysis is realized by force and video data capturing. Using a bubble gum matrix as example, the increase in cutting velocity (from 10 −4 –10 1 m/s) as well as the decrease of sample temperature resulted in a decrease of the viscous contribution of the material and an increase of elastic effects that was reflected by reduced material deformation and brittle fracture during cutting. The holistic description of these effects was realized by interpreting cutting forces, video data, and results of dynamic mechanical analysis. The described test station with high-speed process analysis represents a prominent tool for demonstrating the sensitivity of viscoelastic foods towards temperature and mechanical stresses caused during cutting. [ABSTRACT FROM AUTHOR]