Principle and applications of near-infrared imaging for fruit quality assessment—An overview

The quality (i.e. the degree of excellence and acceptance to the consumer) evaluation and safety of fruit and other agricultural products is by far the main challenging task in the food industries. Hence, the development of efficient non-invasive, real-time and rapid-quality assessment tools and techniques is the need of the hour. This review paper aims to provide the basic or fundamental knowledge regarding the principle, potential and application of near-infrared imaging-based computer vision systems. Non-invasive technologies, based on optical properties, are the most applicable and important for real-time quality assessment. Absorption, reflection and scattering before the transmission of incident light are phenomenon properties of biological materials. The principle and application of NIR imaging (i.e. medical imaging) in agriculture for quality detection were studied from various published research papers. Thus, collected pieces of information are summarised, concluded and discussed in a unique way in this report. The NIR spectrum of electromagnetic waves has some basic benefits of light penetration into the upper layer and makes visualisation of the targeted area of objects. Several studies have proved that the non-destructive system based on visible and non-visible imaging in combination has a significant role in quality defect detection in fruits. In NIR imaging, the artefacts caused by light illumination can be reduced and it will help in the visualisation of biological tissues and hidden defects just below the peel.