Miniaturize proximal sensor for medium-sized fruit senescence

Introduction. In recent years, the integration of advanced technologies into the agricultural and food industries has become a driving force for innovation, efficiency, and sustainability. Among the new technologies, spectroscopy has emerged as a promising tool, demonstrating its efficacy in the analysis of agricultural products. This technique holds the potential to revolutionize the way we monitor and manage the quality of fruits, offering a viable solution to address challenges in the agro-food sector, particularly in minimizing waste and optimizing resource utilization. Spectroscopy involves the study of the interactions between matter and electromagnetic radiation. In the context of agriculture, it has proven to be a versatile tool for assessing the physical and chemical properties of various crops. The use of spectroscopic techniques in agriculture is not a recent development; however, advancements in technology have pushed its application to new heights, making it an indispensable asset for precision farming and quality control. Within this project the focus was to apply a cost-effective portable optical prototype designed for monitoring the ripening and senescence of medium-sized fruits and to compare its performances with a reliable and more complex benchtop instrument. This prototype represents a significant step forward in the field of spectroscopy, particularly in its simplified design and its potential applicability for real-time monitoring especially if used by supply chain operators or even in the future by the end users of the products. The medium-sized matrices taken into consideration in the experimentation include Fuji apples, Passacrassana pears, Dottato figs, and kiwis, presenting a diverse array of samples for a comprehensive analysis of the ripening process. One of the strengths of spectroscopy lies in its ability to acquire a wide range of data deriving from the interaction of light with matter and without destroying the samples. The prototype used in the experimentation works with a limited number of wavelengths (18) ranging from 410 to 940 nanometers, covering both the visible spectrum range and part of the near-infrared range. This allows you to obtain rather complete readouts of the fruit and to be able to take into consideration various parameters related to ripening and not just the color changes that occur in the peel (as some simple instruments available on the market do). The idea is to obtain, with a relatively simple tool, a complete description of the maturation process, from its nascent stages to its final decay. The application of spectroscopy in the agricultural domain has already gained significant traction due to its numerous advantages. It enables non-destructive testing, meaning that the quality and characteristics of fruits can be assessed without compromising their integrity. This non-invasive approach is especially critical for preserving the market value of the produce and ensuring that the end consumer receives a product of optimal quality. In addition to the immediate benefits of real-time monitoring, the project plans to give operators the ability to manage batches effectively, classify products and educate consumers on the quality of the fruit they purchase. This leap would transform the prototype from a diagnostic tool to a tool with far-reaching implications for the agri-food industry. The integration of spectroscopy with some food management practices could represent a turning point in the attempt to reduce waste. By providing information on the state of ripeness and some quality parameters, this technology could provide stakeholders with the knowledge needed to make decisions regarding harvesting, storage and distribution. This, in turn, could significantly reduce the very high levels of waste in the food supply chain. Data and research methodology The experimentation involved the utilization of a cost-effective portable optical prototype specially designed for monitoring the ripening and senescence processes of various medium-sized fruits. This optical device is currently in its prototype phase and represents a simplified version when compared to comprehensive commercial instruments. It operates within a restricted spectrum, employing 18 wavelengths ranging from 410 to 940 nanometers, encompassing both the visible and a segment of the Near-Infrared range. The prototype was applied to samples of Fuji apples, Passacrassana pears, Dottato figs, and kiwis. The objective was to scrutinize the entire ripening progression, starting from the early stages and extending to the point of decay. Simultaneously, the study aimed to validate the effectiveness of this technique and the prototype on matrices with diverse exocarp characteristics. Data acquisition occurred on different sampling days to comprehend variations in optical and qualitative parameters. Subsequently, PLS regression was employed to establish correlations between the optical analyses and destructive data related to Soluble Solids Content (measured in Brix degrees), thus allowing the creation of predictive models. As it is still in the prototype phase, two other commercial instruments were used as a reference: a portable spectrometer operating in the range between 350 and 2500 nanometers and a benchtop instrument operating in the range between 380 and 1650 nanometers. Discussion of results The results obtained from this study exhibit promise, indicating the potential for real-time monitoring of the quality of these fruits. Despite the widespread application of spectroscopy in similar fields due to its manifold advantages, the genuine innovation lies in the envisioned upgrade for the prototype. This advancement is intended to empower operators to oversee batches, classify products, and educate the end consumer. Main conclusions Implementation of these devices could revolutionize the management of harvesting and conservation processes, ultimately optimizing the quality of agricultural products intended for consumption. The envisioned role of the prototype signifies a significant stride towards enhancing operational efficiency in the agricultural sector.