Detection and quantification of cashew in commercial tea products using High Resolution Melting (HRM) analysis

• Main Authors: Georgios Lagiotis, Evangelia Stavridou, Irini Bosmali, Maslin Osathanunkul, Nadia Haider, Panagiotis Madesis
• Format: Journal
• Published: 2020
• Subjects: Agricultural and Biological Sciences
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85085560275&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/70038
• Institution: Chiang Mai University

© 2020 Institute of Food Technologists® Abstract: Tea, a popular aromatic infusion and food supplement, prepared from Camellia sinensis (L.) Kuntze leaves, is often subjected to adulteration with various undeclared inorganic and plant-derived materials. Cashew (Anacardium occidentale L.) nut husk is one of the most common plant tea adulterants. To date, there are limited DNA-based technologies for tea authentication and quantitative detection of adulterants. Herein, we used a universal plant DNA barcoding marker coupled with High Resolution Melting (Bar-HRM) analysis to authenticate tea products from cashew ground nut. Additionally, cashew-specific markers coupled with HRM technology were used to detect and quantify adulteration of tea with cashew DNA. This methodology can reliably detect admixtures as low as 1% v/v cashew in commercial tea products. Overall, our results demonstrate that the HRM technology is a strong molecular approach in tea authentication, capable of detecting very low adulterations in DNA admixtures. Practical Application: In this study, we established the use of high-resolution DNA-based technologies for the detection of cashew adulteration in tea, even in very low quantities. The technology could be applied to a greater range of plant-based tea adulterants. This work is expected to facilitate the traceability and authenticity of tea products and form the basis for the development of strategies against fraudulent practices.