Diferensiasi Kopi Luwak Liar Indonesia dan Kopi Single Origin Dengan Metode Ultraviolet Absorbance Spectroscopy dan Analisis Kemometrik

Alit, Bernadetta Lintang (2026) Diferensiasi Kopi Luwak Liar Indonesia dan Kopi Single Origin Dengan Metode Ultraviolet Absorbance Spectroscopy dan Analisis Kemometrik. Other thesis, Institut Teknologi Sepuluh Nopember.

Text 5009221015-Undergraduate_Thesis.pdf - Accepted Version Restricted to Repository staff only Download (9MB) | Request a copy

Abstract

Indonesia merupakan produsen kopi terbesar keempat di dunia dan dikenal sebagai penghasil kopi luwak berkualitas specialty dengan nilai ekspor mencapai USD 8-10 juta per tahun. Tingginya harga dan permintaan kopi luwak memicu kecurangan berupa pencampuran kopi, kesalahan pelabelan, serta eksploitasi luwak sehingga dibutuhkan metode diferensiasi yang akurat, cepat, dan non-destruktif. Penelitian bertujuan untuk mendiferensiasi kopi luwak liar Indonesia dan kopi single origin menggunakan metode ultraviolet absorbance spectroscopy yang dikombinasikan dengan analisis kemometrik Principal Component Analysis (PCA) dan Hierarchical Cluster Analysis (HCA). Sampel yang digunakan terdiri dari 6 sampel kopi single origin dan 6 sampel kopi luwak liar dari daerah asal yang sama, yaitu Bali Buleleng, Bali Kintamani, Bali Pupuan, Toraja, Mandheling, dan Gayo. Keseluruhan sampel diekstraksi dengan komposisi 0,5 gram bubuk kopi dalam 25 mL air distilasi bersuhu 90-98°C, kemudian diencerkan pada kuvet kuarsa dengan komposisi 0,25 mL ekstrak dan 2 mL aquades. Pengukuran spektral dilakukan menggunakan spektrometer Brolight BIM-6002. Data mentah diolah melalui tahap pre-processing meliputi augmentasi data berbasis mode Offset-Multiplier-Slope (OMS) dan Gaussian noise, cutting spektrum pada panjang gelombang 220-400 nm, substract baseline, Savitzky-Golay smoothing (SG), Standard Normalize Variate (SNV), serta derivative orde pertama, sebelum dianalisis dengan PCA dan HCA. Hasil penelitian menunjukkan perbedaan karakteristik spektral yang jelas pada rentang 220-240 nm (protein), 250-290 nm (trigonelin dan kafein), serta 290-340 nm (asam klorogenat dan melanonidin). Analisis PCA pada data SG smoothing dan SNV menghasilkan nilai cumulative variance tertinggi (96%) dan pemisahan sampel paling jelas dibandingkan data mentah maupun data hasil turunan. Hasil HCA memperkuat temuah tersebut, kopi luwak liar dan single origin dari daerah Bali Pupuan, Toraja, dan Mandheling menunjukkan nilai similariy rendah (0-40%) yang menandakan perbedaan karakteristik spektral jelas, sedangkan sampel dari Bali Kintamani dan Bali Buleleng menunjukkan similarity tinggi (78-93%) akibat kemiripan kandungan asam klorogenat dan melanonidin. Kombinasi ultraviolet absorbance spectroscopy dengan analisis PCA dan HCA terbukti efektif sebagai metode diferensiasi kopi luwak liar Indonesia dan kopi single origin yang non-destruktif, cepat, dan sederhana. Penelitian ini berkontribusi pada SDG 9 (Industry, Innovation, and Infrastructure) melalui pengembangan metode analisis berbasis spektroskopi yang inovatif dan efisien untuk industri pangan, serta SDG 12 (Responsible Consumption and Production) dengan memperkuat standardisasi kualitas dan keaslian produk kopi.
===================================================================================================================================
Indonesia is the fourth lagest coffee-producing country in the world and is known as a producer of high-quality civet coffee, a specialty coffee with an export value reaching USD 8-10 million per year. The high price and demad for civet coffee have triggered widespread fraud, including coffee adulteration, mislabeling, and exploitation of civet, driving the need for accurate, rapid, and non-destructive differentiation methods. This project aims to differentiate Indonesian wild civet coffee and single origin coffee using ultraviolet absorbance spectroscopy combined with chemometric analysis, namely Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). The samples consisted of 6 single origin coffee samples and 6 Indonesian wild civet coffee samples from the same regions of origin: Bali Buleleng, Bali Kintamani, Bali Pupuan, Toraja, Mandheling, and Gayo. The entire sample was extraxted with the composition 0,5 gram of coffee powder in 25 mL of distilled water at 90-98°C, then diluted in a quartz cuvette with composition of 0,25 mL of extract and 2 mL of distilled water. Spectral measurements were performed using a Brolight BIM-6002 spectrometer. Raw data were processed through a pre-processing stage including data augmentation based on Offset-Mutiplier-Slope (OMS) and Gaussian noise modes, spectrum cutting at a wavelength of 220-400 nm, baseline subtraction, Savitzky-Golay smoothing (SG), Standard Normalize Variate (SNV), and first order derivatives, before being analyzed with PCA and HCA. The result shows clear spectral differences at 220-240 nm (protein), 250-290 nm (trigonelline and caffeine), and 290-340 nm (chlorogenic acid and melanonidin). PCA on SG smoothing and SNV data yielded the highest cumulative variance (96%) and the clearest sample separation compared to raw and derivative data. HCA results reinforced these findings: civet and single origin coffee from Bali Pupuan, Toraja, and Mandheling showed low similarity values (0-40%), indicating clear spectral differences, while samples from Bali Kintamani and Bali Buleleng showed high similarity (78-93%) due to similar chlorogenic acid and melanonidin content. The combination of ultraviolet absorbance spectroscopy with PCA and HCA proved effective as a non-destructive, rapid, and simple differentiation method for Indonesian wild civet coffee and single origin coffee. This research contributes to SDG 9 (Industry, Innovation, and Infrastructure) by developing innovative and efficient spectroscopy-based analytical methods for the food industry, and SDG 12 (Responsible Consumption and Production) by strengthening quality and authenticity standardization of coffee products.

Item Type:	Thesis (Other)
Uncontrolled Keywords:	Principal Component Analysis, Hierarchical Cluster Analysis, Diferensiasi Kopi, Kopi Luwak Liar Indonesia, Ultraviolet Spectroscopy, Principal Component Analysis, Hierarchical Cluster Analysis, Coffee Differentiation, Indonesian Wild Civet Coffee, Ultraviolet Spectroscopy
Subjects:	Q Science Q Science > QC Physics Q Science > QC Physics > QC451 Spectroscopy
Divisions:	Faculty of Industrial Technology and Systems Engineering (INDSYS) > Physics Engineering > 30201-(S1) Undergraduate Thesis
Depositing User:	Bernadetta Lintang Alit
Date Deposited:	04 Aug 2026 01:49
Last Modified:	04 Aug 2026 01:49
URI:	http://repository.its.ac.id/id/eprint/142490

Actions (login required)

View Item