Destructive and rapid non-invasive methods used to detect adulteration of dried powdered horticultural products: A review

Adulteration monitoring of processed powdered horticultural products is an important aspect of research in order to facilitate fair trade, ensure food authenticity and safety in the agricultural food industries. Globally, a diversity of horticultural powdered products prone to adulteration include herbs and spices; fruit and vegetable flours; hot beverages and medicinal powdered products. This review article focuses on the utilisation of traditional and non-destructive technologies with emphasis on adulteration detection of powdered horticultural products. Nowadays, infrared spectroscopic technologies (visible to near infrared spectroscopy (Vis/NIRS), Fourier transform infrared (FT-IR), hyperspectral imaging and Raman spectroscopy) are preferred for processed product quality verification over conventional approaches (electrophoretic, gas and liquid chromatographic methods, enzyme-linked immunological assay (ELISA), polymerase chain reaction (PCR) and microscopic methods). Various applications of destructive and non-destructive techniques as well as their limitations in the field of powdered products adulteration detection have been extensively reviewed. A discussion on the concepts of adulteration, adulterants as well as the potential impact on health and agri-food industry is provided. The current status of destructive and rapid infrared methods as well as the future research direction for adulteration detection of powdered horticultural products is outlined. Chemometrics application towards developing excellent robust identification models from spectral data analysis to effectively assess the different adulteration levels of spices/herbs, hot beverage powders, fruit/vegetable flours and medicinal powdered products are illustrated.