Principal Component Analysis of Commercial Tannin Extracts Using Digital Images on Mobile Devices

Fábio S Grasel,Adilson B Costa,Gilson A Helfer,Marco F Ferrão

doi:10.5935/0103-5053.20160135

Abstract

Tannins from trees are an abundant renewable resource. The use of tannins is safe for the environment and human health, making it possible to develop environmentally friendly products, such as adhesives, flocculant agents for water treatment, flame retardant foams and anticorrosives. In this study, a methodology was developed for the identification of six commercial tannin extracts (chestnut, valonea, tara, myrobalan, quebracho and black wattle) using digital images on mobile devices. The identification of the extracts was based on principal component analysis using the PhotoMetrix® mobile application. In the evaluation of the principal components, it was possible to define the separation between the six classes of extracts by color evaluation, according to the extract origin. In the analysis of PC1 × PC2, black wattle was very close to quebracho and chestnut was close to valonea; these extracts are chemically similar. The methodology developed for the analysis of tannin extracts obeys the principles of green chemistry requiring no reagents, and is fast, non-destructive and inexpensive.

Highlights

Tannins are polyphenolic extracts widely found in the plant kingdom; they are synthesized by plants during growth and in response to stress conditions.[1]
Analyzing the results of the decomposition of the data through principal component analysis (PCA) (Figures 3-5), it can be seen that 100% of the total variance was explained in the first 3 PCs
30 samples of polyphenolic extracts representing six commercially available types were analyzed by digital images using the PhotoMetrix® mobile application

Summary

Introduction

Tannins are polyphenolic extracts widely found in the plant kingdom; they are synthesized by plants during growth and in response to stress conditions.[1]. Chestnut and valonea samples showed the greatest similarity, indicating that these extracts have an equivalent chemical composition, in agreement with the literature.[20,21,22,23,24] A new methodology is proposed based on digital images taken on a smartphone, using the new PhotoMetrix®34,35 application for the identification of tannins according the source type (chestnut, valonea, quebracho, black wattle, tara and myrobalan).

Results

Conclusion