Ta x2i texture analyser

The hardness of the shells from randomly chosen organisms of each treatment was tested using TA-X2i Texture Analyser (Stable Micro Systems; Godalming, UK).
With the shells firmly held in a metal surface, a 4 mm diameter metal cylinder probe (TA-56) was lowered at a constant speed of 1 mm/s until rupture occurred; the force was applied vertically along the axis at gastropod shell apex. Using a 30 kg load cell, the maximum force (N) applied was registered by the apparatus software Texture Exponent 32 (version 6.1.12.0, Stable Micro Systems; Surrey, UK). The shell hardness (SH) was calculated by dividing the maximum force obtained by the ratio of diameter/height of the shells, which allowed to take into account the size variations of the organisms.

Following thermal treatment of the stored and fresh samples and a cooling step of 5 min, the hardness of cotyledons was determined by measuring the compression force using a TA-X2i texture analyser (Stable Microsystems, Goldaming, England). It was equipped with a 25 kg force cell and a cylindrical flat-head aluminium probe of diameter 25 mm which was utilised to compress a cotyledon to 75% strain at a speed of 1 mm/s. The maximum peak force (gram-force, g) recorded from compression of a half a cotyledon was defined as the hardness. At least 20 cotyledons of different seeds from the different cooking times were measured, to obtain an evolution of hardness with storage (Chigwedere, Olaoye, et al., 2018) (link).