Design and development of a food texture analyser : a thesis presented in partial fulfillment of the requirements for the degree of Master of Engineering in Mechatronics at Massey University, Manawatu, New Zealand

Abstract

Texture is an important attribute of food and is one of the several dimensions of food quality. In today’s world of sensing and automated measurements, it is becoming increasingly common to analyse food by using a texture analyser. A variety of texture analysers is in use by researchers and industry for the purpose of quality assurance and improvements. This thesis is on the design, development and implementation of a food texture analyser with a focus on enhancing response time, increasing measurement flexibility, and reducing equipment cost. Several enhancements have been done to an existing texture analyser. A high-end 24-bits ADC (Analogue to Digital Convertor) has been used to measure the output of a load cell very accurately. The output of the ADC is coupled to a modern microcontroller using the industry standard SPI bus. A touch screen has been incorporated to provide an easy user interface. A completely new motor controller/driver has been employed for the movement of the robotic arm and an infra-red sensor has been used to detect its position. A unique and novel contribution is in the form of a new command-language that has been developed which makes it extremely flexible for the user to control the motor movements. An enhancement, not found in existing commercial texture analysers, is the real-time graphing of measurement data which is displayed on the PC. Additionally all the data can be saved to a text file or a CSV file for subsequent retrieval and processing. The complete system has been realised and tested. Several different fruits were used for experiments and the measurement data compared with a commercial texture analyser. The system is simple to use, versatile and low cost for use in research and industry.