The potato (Solanum tuberosum) is the most important non-grain vegetable in the world, playing a major role in human nutrition worldwide. Half of all potato grown, however, does not reach the fork of the consumer. Food waste and losses represent a substantial challenge to potato supply chains, as well as to global food systems in general. Food waste and losses negatively impact the world in a variety of ways, contributing to food insecurity, environmental degradation and economic losses. A leading cause of potato waste and losses is tuber defects, which result in produce failing to meet safety, storage or consumer standards. While defects with external symptoms are effectively screened for via optical grading lines, many defects exhibit only internal defects, which is a barrier to their detection. Internal defects are widely screened for by solely destructive means; novel non-destructive approaches are needed to improve the detection and screening of internal potato defects. Work carried out in this thesis investigates the potential for non-invasive non-destructive approaches to detect internal potato defects to address the challenges they pose to the fresh potato supply chain. This research uncovers promising avenues of non-invasive non-destructive detection of internal potato defects, applying optical and electrical spectroscopy. NIR reflectance spectroscopy successfully provided a means of detecting blackheart and spraing in intact potatoes. Blackheart was also successfully detected with a novel approach to impedance spectroscopy. In addition to these findings this work develops an exciting novel method for extending the shelf-life of fresh produce such as tomatoes to reduce losses in homes, retail and transit.
Ed Hill-King (Thu,) studied this question.