Optical techniques in non-destructive detection of wheat quality: A review

Wheat quality detection is essential to ensure the safety of wheat circulation and storage. The traditional wheat quality detection methods mainly include artificial sensory evaluation and physicochemical index analysis, which are difficult to meet the requirements for high accuracy and efficiency in modern wheat quality detection due to the disadvantages of subjectivity, destruction of sample integrity and low efficiency. With the rapid development of optical technology, various optical-based methods, using near-infrared spectroscopy technology, hyperspectral imaging technology and terahertz, etc., have been proposed for wheat quality detection. These methods have the characteristics of non-destructiveness and high efficiency which make them popular in wheat quality detection in recent years. In this paper, various state-of-the-art optical-based techniques of wheat quality detection are analyzed and summarized in detail. Firstly, the principle and process of common optical non-destructive detection methods for wheat quality are introduced. Then, the optical techniques used in these detection methods are divided into seven categories, and the comparison of these technologies and their advantages and disadvantages are further discussed. It shows that terahertz technology is regarded as the most promising wheat quality detection method compared with other optical detection technologies, because it can not only detect most types of wheat deterioration, but also has higher accuracy and efficiency. Finally, the research of optical technology in wheat quality detection is prospected. The future research of optical technology-based wheat quality detection mainly includes the construction of wheat quality optical detection standardization database, the fusion of multiple optical detection technologies and multiple quality index information, the improvement of the anti-interference of optical technology and the industrialization of optical inspection technology for wheat quality. These studies are of great significance to improve the detection technology of wheat and ensure the storage safety of wheat in the future.