Applications of hyperspectral imaging in grains and nuts quality and safety assessment: a review

Quality of foods is generally controlled with traditional methods such as microbiological and chemical tests. However, the necessity of a non-destructive, rapid and accurate on-line method to monitor the product quality and safety is the key topic of many research studies. Hyperspectral imaging (HSI) has emerged as a powerful tool to handle the afore-mentioned goals. It is a novel technique that combines simultaneous advantages of imaging and spectroscopy. HSI is an analytical method that simultaneously delivers chemical, structural and functional information from the sample. This technique can be used to analyze both individual kernels and bulk samples and simultaneously determine quality parameters of grains and nuts. Nuts and grains are nutrient dense foods with complex matrices rich in mono- and poly-unsaturated fatty acids, vegetable proteins, fiber, vitamins, minerals etc. Therefore, nuts and grains are useful dietary sources to decrease the risk of diabetes, cancer and cardiovascular disease. In this paper, recent applications of hyperspectral imaging in quality and safety inspection of nuts and grains such as classification, compositions prediction, texture analysis, and detection of varietal impurities, damages, and infections are reviewed.