Application of a depth sensing indentation hardness test to evaluate the mechanical properties of food materials

Özkan, Necati
A depth sensing indentation hardness test with an associated analysis is described as a convenient and simple technique for characterizing mechanical properties of food materials, such as hardness (H), elastic modulus (E), and an elasticity index (I-E) which represents the ratio of elastic to total deformation. Storage modulus (G) and loss tangent (tandelta) of the selected model food material, a whey protein concentrate (WPC) gel, have also been determined using an oscillatory dynamic testing. Fractal dimension (D) and strain rate (or frequency) exponent (n) of the WPC gels were determined using both the indentation and dynamic test results. A good correlation between the results from the indentation and the dynamic tests was established. The effects of protein concentration, deformation rate, and chemical treatment on the mechanical properties of the WPC gels were clearly illustrated using the indentation test.


Şener, Özgün; ATALAY, OĞUZ; ATASOY, MERT; Kayran, Altan (2018-11-15)
Transverse shear moduli of the sandwich core and flexural stiffness of all-composite sandwich constructions are determined with three-point beam bending tests, and compared with the analytical and finite element analysis solutions. Additionally, Digital Image Correlation (DIC) system is employed to validate the experimental results by monitoring the displacements. The effect of orientation of the composite core material with respect to the beam axis on the shear modulus of the core material itself, flexural...
Evaluation of cement mortars by ultrasound
Paksoy, Nesibe Gözde; Yaman, İsmail Özgür; Department of Civil Engineering (2006)
Ultrasonic testing of concrete is often used for the assessment of its uniformity, strength, modulus of elasticity, durability and etc. therefore, the related parameters of testing such as the transducer frequency, the specimen geometry and etc. are well-known. On the other hand, most of the concrete properties are affected by the cement and the mechanical as well as some durability properties of cements are determined through cement mortars. Applications of ultrasound on determining the properties of cemen...
Analysis of flexible pavements incorporating nonlinear resilient behavior of unbound granular layers
Karagöz, Cem; Acar, Soner Osman; Department of Civil Engineering (2004)
Traditionally, the resilient modulus values obtained from repeated unconfined or triaxial compression tests are used as the elastic modulus of granular layers in structural analysis of flexible pavements. Sometimes the resilient modulus of granular materials are estimated from known California bearing ratios (CBR) or stabilometer resistance (R) values by simple regression equations. On the other hand, it is well known that stress-strain relation for unbound granular materials is nonlinear and the resilient ...
Sliding frictional contact between a rigid punch and a laterally graded elastic medium
Dağ, Serkan; Yidirim, Bora; Ozatag, A. Cihan (2009-11-01)
Analytical and computational methods are developed for contact mechanics analysis of functionally graded materials (FGMs) that possess elastic gradation in the lateral direction. In the analytical formulation, the problem of a laterally graded half-plane in sliding frictional contact with a rigid punch of an arbitrary profile is considered. The governing partial differential equations and the boundary conditions of the problem are satisfied through the use of Fourier transformation. The problem is then redu...
Hybrid finite element for analysis of functionally graded beams
Sarıtaş, Afşin; Soydas, Ozan (2017-01-01)
A hybrid finite element model is presented, where stiffness and mass distributions over a beam with functionally graded material (FGM) are accurately modeled for both elastic and inelastic material responses. Von Mises and Drucker-Prager plasticity models are implemented for metallic and ceramic parts of FGM, respectively. Three-dimensional stress-strain relations are solved by a general closest point projection algorithm, and then condensed to the dimensions of the beam element. Numerical examples and veri...
Citation Formats
N. Özkan and X. CHEN, “Application of a depth sensing indentation hardness test to evaluate the mechanical properties of food materials,” JOURNAL OF FOOD SCIENCE, pp. 1814–1820, 2002, Accessed: 00, 2020. [Online]. Available: