The classification of arabica gayo wine coffee using UV-visible spectroscopy and PCA-DA method

IOP Conf. Ser.: Earth Environ. Sci.

Ningtyas

Suharyatun

et al. 2022

Arabica coffee variety is one of the key parameters that highly influence the cup quality of arabica coffee. The objective of this current research is to evaluate the possible application of UV spectroscopy for the discrimination of arabica coffee with different cultivars. Green beans from two arabica coffee cultivars (Coffea arabica) of Typica and Sigarar Utang were collected from the same origin in Papandayan mountain West Java, Indonesia. The samples were subjected to the same postharvest treatments (wet cherry processing method). All samples were roasted in medium roasting with 200°C for 16 minutes using a portable roasting machine. A total of 40 samples of Typica and Sigarar Utang were provided by weighing 1 gram of coffee powder (mesh 40) for each sample. The extraction of coffee samples was performed based on previously reported work. The UV-visible spectral data of aqueous coffee samples were acquired by using a benchtop of UV-vis spectrometer in the range of 190-1100 nm. The first two PCs (principal components) with 94% of CEV (cumulative explained variance) could be used to separate between the Typica and Sigarar Utang samples. The Typica samples were situated on the left of PC1 (PC1<0) and Sigarar Utang samples were on the right of PC1 (PC1>0). In the future, it is promising to apply UV spectroscopy for simple and reliable discrimination of arabica coffee cultivar.

Section: Spectra Of Arabica Sigarar Utang and Typicasupporting

confidence: 87%

“…A total of 40 samples of Typica and Sigarar Utang were provided by weighing 1 gram of coffee powder (mesh 40) for each sample. The extraction of coffee samples was performed based on previously reported work [19]. Figure 1 shows arabica Sigarar Utang and arabica Typica coffee samples before extraction.…”

Section: Samplesmentioning

confidence: 99%

UV spectroscopy for discrimination of two arabica coffee cultivars in West Java Indonesia: a feasibility study

IOP Conf. Ser.: Earth Environ. Sci.

Ningtyas

Suharyatun

et al. 2022

“…All samples were extracted using a protocol as explained by previous works [14][15][16][17]. For each sample, 50 mL of hot distilled water (98 • C) was added and then well stirred for 10 min using CiBlanc magnetic stirrer.…”

Section: Coffee Extraction Using Distilled Watermentioning

confidence: 99%

“…UV spectroscopy has been used for specialty coffee authentication, especially for ground roasted coffee. Suhandy and Yulia [14][15][16][17] studied the application of UV spectroscopy and chemometrics for authentication of Luwak coffee, peaberry coffee, several Indonesian specialty coffees with a geographic indication (GIs) and discriminating Gayo wine and normal coffee.…”

Section: Introductionmentioning

confidence: 99%

Classification of Lampung robusta Specialty Coffee According to Differences in Cherry Processing Methods Using UV Spectroscopy and Chemometrics

Suhandy

2021

Agriculture

Self Cite

The postharvest processing factors including cherry processing methods highly influence the final quality of coffee beverages, especially in the composition of several coffee metabolites such as glucose, fructose, the amino acid (glutamic acid), and chlorogenic acids (CGA) as well as trigonelline contents. In this research, UV spectroscopy combined with chemometrics was used to classify a ground roasted Lampung robusta specialty coffee according to differences in the cherry processing methods. A total of 360 samples of Lampung robusta specialty coffee with 1 g of weight for each sample from three different cherry processing methods were prepared as samples: 100 samples of pure dry coffee (DRY), 100 samples of pure semi-dry coffee (SMD), 100 samples of pure wet coffee (WET) and 60 samples of adulterated coffee (ADT) (SMD coffee was adulterated with DRY and WET coffee). All samples were extracted using a standard protocol as explained by previous works. A low-cost benchtop UV-visible spectrometer (Genesys™ 10S UV-Vis, Thermo Scientific, Waltham, MA, USA) was utilized to obtain UV spectral data in the interval of 190–400 nm using the fast scanning mode. Using the first three principal components (PCs) with a total of 93% of explained variance, there was a clear separation between samples. The samples were clustered into four possible groups according to differences in cherry processing methods: dry, semi-dry, wet, and adulterated. Four supervised classification methods, partial least squares–discriminant analysis (PLS-DA), principal component analysis–linear discriminant analysis (PCA-LDA), linear discriminant analysis (LDA) and support vector machine classification (SVMC) were selected to classify the Lampung robusta specialty coffee according to differences in the cherry processing methods. PCA-LDA is the best classification method with 91.7% classification accuracy in prediction. PLS-DA, LDA and SVMC give an accuracy of 56.7%, 80.0% and 85.0%, respectively. The present research suggested that UV spectroscopy combining with chemometrics will be highly useful in Lampung robusta specialty coffee authentication.

“…Total 150 samples were created by weighing 1 gram for each sample of coffee powder for organic Lampung Barat coffee (n=50), conventional Lampung Barat coffee (n=50), and conventional Tanggamus coffee (n=50). A standard protocol for coffee extraction using distilled water was adopted as explained in previous studies [11][12].…”

Section: Coffee Samplesmentioning

confidence: 99%

UV spectral analysis coupled with PCA-LDA to classify organic and conventional Lampung robusta coffee from different origins

IOP Conf. Ser.: Earth Environ. Sci.

Suhandy

2022

This current research presents a simple analytical method for classifying organic and conventional coffee samples from different origins. UV pre-processed spectral data in the range of 250-400 nm was used to discriminate between organic Lampung robusta coffee from Lampung Barat (n=50) and two conventional Lampung robusta coffees from Lampung Barat (n=50) and Tanggamus (n=50). Ground roasted coffee samples with 50 mesh were used for samples. UV-vis spectrometer was utilized to acquire UV spectral data from an aqueous coffee sample. A chemometric method based on PCA and PCA-LDA algorithm was used to classify the samples. The PCA result shows all organic coffee samples were clustered on the negative of PC1 while all conventional coffee samples were on the positive of PC1. The conventional coffee samples from Lampung Barat and Tanggamus were grouped in different clusters according to their origin. The PCA-LDA resulted in a 100% accuracy in classification both for calibration and prediction. This method is a promising approach for organic Lampung robusta authentication with a relatively low-cost spectrometer and simple sample preparation.