Young's modulus estimation in food samples: Effect of experimental parameters

Texture is an important attribute in the quality assessment of processed food products. Recently, Young's modulus is identified as one of the most important indicators of food texture. However, there is much ambiguity in the literature about quantification and standards for texture analysis. In this paper, the sensitivity of Young's modulus (and thus texture) towards the applied deformation rate, sample shape and size, moisture content is studied experimentally for potato and sweet potato samples. We found that Young's moduli vary by as much as 54% depending on the rate of applied strain, indicating the need for test standards. The strain rate dependent behaviour exhibits the viscoelastic nature of the potato samples, which was further validated by stress relaxation and cyclic tests. Based on our experimental iterations and associated finding of the work, we propose the need for a standardised procedure for measuring Young's modulus and texture analysis. We expect this work to serve as a crucial step toward standardised texture measurement during thermal processing of food products.