Study On Bionic Detection Method Of Physical Properties Of Viscoelastic Food Materials

The deformation mechanism of the viscoelastic food materials in specific processing mode not only affects the food materials processing technology, but also influences food taste in the process of chewing. At the same time, it is of great significance to describe the viscoelastic properties of viscoelastic materials with accurate mathematical method for the research of viscoelastic material.Current testing methods of texture properties on viscoelastic food materials is mainly divided into sensory evaluation and instrument measuring method.Sensory evaluation method mainly depends on the human sensory analysis, it has strong subjectivity, While the instrument test method has strong objectivity, eliminating the effect of human subjectivity. As the representative, texture analyzer Instrument measuring method is widely used, of which the TPA program is the simulation to human two chewing process.Use TPA testing for biomimetic detection of texture properties and get the closest results to the human sensory evaluation results. Correlation analyzation between the test results of the instrument itself and the human sensory evaluation conclusion is needed, in order to increase the credibility of experimental results.Wheareas, the results of testing are affected by the test conditions, so the influence analyzation of experimental conditions on the experimental results was firstly analyzed, which could concluded the optimal experimental conditions.After the preparatory work is completed, it is more reliable to equivalent modeling of viscoelastic materials.At first of all, this article was focused on the chewing mechanism of the viscoelastic food materials in the mouth. Due to the complicated chewing movement, the simplified method and process(compression, shearing, crushing) separation were applied to analyze. Maxwell model and Kelvin model, which characterized small deformationare are used to describe the compression deformation condition of nonlinear viscoelastic material, but the description on characteristics of the material is single in comparison with large deformation condition, which needs to be further studied. Taking the viscoelastic food materials as the subject by stress relaxation tests and strain relaxation tests of texture analyzer equipment, based on Maxwell and Kelvin model, proposing a method to build a composite model which can more precisely describe the mechanical behavior of the viscoelastic food material under the mode of compressed, selecting the methods of different constructed composite model, making analysis and comparison between constructed composite model with Maxwell, Kelvin model, verified that the building composite model can better describe the mechanical behavior of viscoelastic food material under the mode of compressed and large deformation. Secondly, after shear experiments of starch, the memory equation of the starch materiasl is established and obtained a good verification. They both provided a more precise theoretical model for the processing and development of viscoelastic food material. Through the compression and shear experiments on two kinds of special material, it provided a concrete and effective modeling method for viscoelastic food material. At the end of the paper, the mechanism design on this topic research results for physical bionic detection method was describered clearly. Either flow viscoelastic materials(such as starch solution) or solid viscoelastic material(e.g., bread),by constructing the relationship models between stress and strain of the material, on the onehand, it can provide the theoretical data for the designof food material processing equipment, what’s more, it can provide specify guidance for the material processing technology parameters, and provides theory control model for this kind of material texture characteristics of the bionic testing instrument testing control. At the same time, the equivalent damping material can be found in the actual engineering instead of limited industrial materialresources by establishing the model of material, which can also solve the problem of viscoelastic material transportation easily.