Affiliations: [a] Department of Food Technology, Faculty of Sciences, Chulalongkorn University, Bangkok, Thailand
| [b] The Novel Technology for Food Packaging & Control of Shelf Life Research Group, Chulalongkorn University, Bangkok, Thailand
| [c] Food Science and Technology Division, Faculty of Home Economics Technology, Rajamangala University of Technology Krungthep, Sathon, Bangkok, Thailand
| [d] Department of Food, Environmental and Nutritional Sciences (DeFENS), Università deli Studi di Milano, Via Celoria 2, 20133 Milano, Italy
Abstract: INTRODUCTION:The consumption of mulberry leaf tea is popularly increasing worldwide due to its potential health benefit associated with phenolic compounds. To ensure the quality, the content of phenolic compounds of mulberry leaf tea need to be monitored throughout the storage period. OBJECTIVE:This research proposed a rapid prediction of phenolic compounds and antioxidant activity of mulberry leaf tea using an electronic tongue (e-tongue). METHODS:Total phenolic content (TPC), total flavonoids content (TFC) and antioxidant activity (FRAP and DPPH) of mulberry leaf tea stored at 30–60°C for 12 months were measured by an e-tongue and conventional chemical analyses. Partial least squares (PLS) regression was applied to predict chemicals parameters by e-tongue data. RESULTS:The PLS models for TPC, TFC, FRAP, and DPPH achieved good predictability with high values of coefficient of determination (
= 0.956, 0.964, 0.926, and 0.943, respectively) and gave low mean square error of prediction. CONCLUSION:The results demonstrated that e-tongue can be applied as a rapid and non-destructive tool for the simultaneous evaluation of phenolics compounds and antioxidant activity to ensure the quality and health benefits of mulberry leaf tea.
Keywords: Herbal tea, Morus alba
, phytochemicals, biological activity, e-tongue, partial least squares regression