Innovative Hyperspectral Imaging-Based Techniques for Quality Evaluation of Fruits and Vegetables: A Review

Abstract

New, non-destructive sensing techniques for fast and more effective quality assessment of fruits and vegetables are needed to meet the ever-increasing consumer demand for better, more consistent and safer food products. Over the past 15 years, hyperspectral imaging has emerged as a new generation of sensing technology for non-destructive food quality and safety evaluation, because it integrates the major features of imaging and spectroscopy, thus enabling the acquisition of both spectral and spatial information from an object simultaneously. This paper first provides a brief overview of hyperspectral imaging configurations and common sensing modes used for food quality and safety evaluation. The paper is, however, focused on the three innovative hyperspectral imaging-based techniques or sensing platforms, i.e., spectral scattering, integrated reflectance and transmittance, and spatially-resolved spectroscopy, which have been developed in our laboratory for property and quality evaluation of fruits, vegetables and other food products. The basic principle and instrumentation of each technique are described, followed by the mathematical methods for processing and extracting critical information from the acquired data. Applications of these techniques for property and quality evaluation of fruits and vegetables are then presented. Finally, concluding remarks are given on future research needs to move forward these hyperspectral imaging techniques.

Effect of fruit moving speed on online prediction of soluble solids content of apple using Vis/NIR diffuse transmission

“…Apple is worldwide favored by consumers because of its nutritious value (Giovanelli, Sinelli, Beghi, Guidetti, & Casiraghi, 2014;Mendoza, Lu, & Cen, 2014). With consistent attention to high-quality fruits at a reasonable price, the demand of automatic, accurate and quick detection still grows (Lu, Huang, & Lu, 2017). Soluble solids content (SSC) plays a decisive role in the consumer purchasing decision on fruits (Sun, Lin, Xu, & Ying, 2009).…”

Hyperspectral Imaging System with Rotation Platform for Investigation of Jujube Skin Defects

“…Hyperspectral imaging, combining conventional two-dimensional imaging and spectroscopic techniques, produces a three-dimensional image data cube, and records the spatial and spectral information simultaneously [13]. In recent years, many researchers have demonstrated the feasibility of hyperspectral imaging systems in detecting skin defects of fruit [14,15]: bruise on apple and pear [4,16], chilling injury in peaches [17,18], decay in citrus [5,19], fungal infections in strawberry [20], and green mold pathogens on lemons [21] to name a few.…”

Time-Domain Functional Diffuse Optical Tomography System Based on Fiber-Free Silicon Photomultipliers

“…Diffuse Optical Tomography (DOT) in the near infrared spectrum is a valuable tool for many applications, like breast cancer analysis [1][2][3][4][5], functional imaging [6,7], small-animals imaging [8], and non-destructive assessment of food quality [9,10]. In fact, the main chromophores that are present in biological tissues feature a low absorption coefficient (µ a < 0.1 mm −1 ) and a high reduced scattering coefficient (µ s ≈ 1 mm −1 ) to radiation within the so-called therapeutic window (600-1100 nm), thus permitting light to propagate for long pathlengths and to be detected when re-emitted outside of the tissue.…”