Technological innovations for reducing tomato loss in the agri-food industry

Food loss and waste has a detrimental impact on the economy, food security and the environment, especially at a time when more than 700 million people around the world suffer from hunger. Fruit and vegetables are highly perishable products and, as a result significant amounts are wasted at various stages of the food supply chain. In addition to this, the hard truth is that a high percentage of fresh produce is wasted because it does not meet quality requirements, mainly in terms of aesthetics. One potential solution to reduce fruit and vegetables losses would be to implement technologies in the industry capable of identifying products that may then be discarded at their destination, which will lead to the search for other commercial strategies, including valorization ones. With this focus, the case of tomato, one of the most produced and consumed commodities worldwide and responsible for high food losses, is addressed in this review. Gas sensors, e-nose systems, acoustic technologies, various spectroscopic techniques, as well as optical imaging techniques, have been proposed for non-invasive monitoring of tomato quality parameters. Indeed, their use has allowed the analysis of CO₂, ethylene and aroma components, as gas indicators of the physiological state of the fruit, to detect the presence of surface defects and to estimate, color, firmness, titratable acidity, and the content of total soluble solids and bioactive compounds. However, despite their promising results, most of them have important drawbacks for industrial applications. Among the reviewed technologies, multispectral and hyperspectral analysis are particularly advantageous due to their ability to monitor multiple tomatoes quality parameters and their possibility to operate in online multisensory platforms. The review provides, for the first time to our knowledge, a comprehensive overview of the current scientific efforts and knowledge gaps, as well as future directions of the non-invasive techniques investigated for the analysis of tomato quality parameters. These considerations are crucial for the development of technological solutions to be implemented in the agri-food industry in order to minimize food waste while improving process quality and efficiency, thus contributing to a more circular food system.