D-Optimal Design and PARAFAC as Useful Tools for the Optimisation of Signals from Fluorescence Spectroscopy Prior to the Characterisation of Green Tea Samples
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A procedure based on a D-optimal design coupled with PARAFAC was proposed to optimise signals from molecular fluorescence spectroscopy to obtain the best experimental conditions for the achievement of the best fluorescence signal of green tea samples. Excitation-emission signals (EEMs) were used to analyse the liquid samples (tea infusions), whereas front-face fluorescence excitation-emission matrices (FFEEMs) were recorded for the solid samples (raw or powder tea leaves). The experimental effort was reduced considerably in both cases thanks to the D-optimal design. Once the optimal conditions have been found, the characterisation of green tea was carried out and the sensitivity and specificity were evaluated. The projection of the principal component analysis (PCA) scores enabled to differentiate among the types of liquid green tea (Chinese tea, Chinese tea with lemon and Indian tea with and without theine). The discrimination of solid green tea according to its geographical origin (Chinese, Indian and Japanese) was also carried out through PCA. In addition, the discrimination between the most expensive Japanese tea and the cheapest one was possible. The sensitivity of the models built with SIMCA was 100% and the specificity of the models for the Chinese tea with respect to the Japanese tea was also high.
KeywordsGreen tea Front-face fluorescence spectroscopy D-optimal design PARAFAC PCA Characterisation
The study was financially supported by the Spanish Ministerio de Economía y Competitividad/Agencia Estatal de Investigación (AEI) (CTQ2014-53157-R and CTQ2017-88894-R) and Junta de Castilla y León (BU012P17). All were co-financed with European FEDER, EU funds.
Compliance with ethical standards
Conflict of interest
M. Hooshyari declares that she has no conflict of interest. L. Rubio declares that she has no conflict of interest. M. Casale declares that she has no conflict of interest. S. Furlanetto declares that she has no conflict of interest. F. Turrini declares that she has no conflict of interest. L.A. Sarabia declares that he has no conflict of interest. M.C. Ortiz declares that she has no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
- Andersson CA (1998) INCA 1.41. Department of Food Science, University of Copenhagen, Denmark. Available from: http://www.models.life.ku.dk/inca. Accessed 30 Nov 2018
- Balentine DA, Harbowy ME, Graham HN (1998) Caffeine. In: Spiller GA (ed) Tea: the plant and its manufacture; chemistry and consumption of the beverage. CRC Press, USA, pp 35–72Google Scholar
- Casale M, Pasquini B, Hooshyari M, Orlandini S, Mustorgi E, Malegori C, Turrini F, Ortiz MC, Sarabia LA, Furlanetto S (2018) Combining excitation emission matrix fluorescence spectroscopy, parallel factor analysis, cyclodextrin-modified micellar electrokinetic chromatography and partial least squares class-modelling for green tea characterization. J Pharm Biomed Anal 159:311–317.CrossRefGoogle Scholar
- FAO (2015) Word tea production and trade. Current and future development, RomeGoogle Scholar
- Forina M, Lanteri S, Armanino C, Casolino MC, Casale M, Oliveri P (2012) V-PARVUS 2012. An extendable package of programs for explorative data analysis, classification and regression analysis, Dept. of Pharmacy, University of Genoa.Google Scholar
- Hicks A (2009) Current status and future development of global tea production and tea products. AU JT 12:251–264Google Scholar
- Jagan Mohan Rao L, Ramalakshmi R (2011) Recent trends in soft beverages. Woodhead Publishing India PVT LTD, IndiaGoogle Scholar
- Kapoor MP, Rao TP, Okubo T, Juneja LR (2013) Green tea: history, processing techniques, principles, traditions, features, and attractions. In: Juneja LR, Kapoor MP, OkuboT RT (eds) Green tea polyphenols nutraceuticals of modern life. CRC Press, USA, pp 1–18Google Scholar
- Lewis GA, Mathieu D, Phan-Tan-Luu R (1999) Pharmaceutical and experimental designs. Marcel Dekker, New YorkGoogle Scholar
- Mathieu D, Nony J, Phan-Tan-Luu R (2015) NemrodW, Version 2015. L.P.R.A.I., MarseilleGoogle Scholar
- MATLAB (2014) version 188.8.131.52421 (R2014b). The Mathworks, Inc., NatickGoogle Scholar
- Ortiz MC, Sarabia LA, Sánchez MS, Herrero A, Sanllorente S, Reguera C (2015) Usefulness of PARAFAC for the quantification, identification, and description of analytical data. In: Muñoz de la Peña A, Goicoechea HC, Escandar GM, Olivieri AC (eds) Data handling in science and technology: fundamentals and analytical applications of multiway calibration. Elsevier, AmsterdamGoogle Scholar
- Saeed M, Naveed M, Arif M, Ullah Kakar M, Manzoor R, Ezzat Abd El-Hack M, Alagawany M, Tiwari R, Khandia R, Munjal A, Karthik K, Dhama K, Iqbal HMN, Dadar M, Sun C (2017) Green tea (Camellia sinensis) and L-theanine: Medicinal values and beneficial applications in humans-a comprehensive review. Biomed Pharmacother 95:1260–1275CrossRefGoogle Scholar
- Wise BM, Gallagher NB, Bro R, Shaver JM, Windig W, Koch RS (2015) PLS Toolbox 7.9.5. Eigenvector Research Inc., WenatcheeGoogle Scholar