Evaluasi Rasio Bahan terhadap Media dan Waktu Perendaman pada Proses Dekafeinasi berdasarkan Penurunan Kafein serta Karakteristik Fisikokimia dan Sensori

Abstract

Kopi robusta (Coffea canephora) memiliki kadar kafein relatif tinggi sehingga diperlukan proses dekafeinasi yang efektif dengan tetap mempertahankan karakteristik kopi. Penelitian ini bertujuan mengevaluasi rasio bahan terhadap media perendaman dan waktu perendaman yang sesuai pada proses dekafeinasi biji kopi robusta menggunakan ekstrak labu siam (Sechium edule). Penelitian dilakukan melalui evaluasi kinetika penyerapan air pada rasio kopi terhadap ekstrak 1:2, 1:4, 1:5, 1:7, dan 1:10 menggunakan model Peleg. Rasio 1:5 ditetapkan berdasarkan hasil pemodelan untuk dievaluasi bersama rasio 1:4 selama 24 jam. Pemilihan rasio selanjutnya dilakukan berdasarkan penurunan kafein serta karakteristik fisikokimia dan sensori. Rasio terpilih kemudian dievaluasi pada waktu perendaman 24 dan 48 jam pada suhu 45 °C. Parameter yang dianalisis meliputi kadar kafein, kadar air, aktivitas air, pH, warna, kadar protein, total asam tertitrasi, karakteristik sensori, dan Acceptance Index (AI). Rasio 1:5 selama 24 jam menghasilkan kadar kafein 0,91% dengan penurunan 55,52% dan AI 61,20%, sedangkan perendaman 48 jam menghasilkan kadar kafein 0,74% dengan penurunan 63,80% dan AI 54,80%. Berdasarkan keseluruhan parameter evaluasi, rasio 1:5 dengan waktu perendaman 24 jam ditetapkan sebagai kondisi terpilih.

Robusta coffee (Coffea canephora) has a relatively high caffeine content, necessitating an effective decaffeination process while maintaining coffee characteristics. This study aimed to evaluate an appropriate material-to-immersion- medium ratio and immersion time for the decaffeination of robusta coffee beans using chayote extract (Sechium edule). The study evaluated water absorption kinetics at coffee-to-extract ratios of 1:2, 1:4, 1:5, 1:7, and 1:10 using the Peleg model. A ratio of 1:5 was selected based on the model results for further evaluation alongside the 1:4 ratio for 24 h. Ratio selection was subsequently based on caffeine reduction as well as physicochemical and sensory characteristics. The selected ratio was then evaluated at immersion times of 24 and 48 h at 45°C. The analyzed parameters included caffeine content, moisture content, water activity, pH, color, protein content, total titratable acidity, sensory characteristics, and Acceptance Index (AI). The 1:5 ratio with 24 h of immersion resulted in a caffeine content of 0.91%, corresponding to a 55.52% reduction and an AI of 61.20%, whereas 48 h of immersion resulted in a caffeine content of 0.74%, corresponding to a 63.80% reduction and an AI of 54.80%. Based on the overall evaluation, a 1:5 ratio with 24 h of immersion was selected as the preferred condition.