Extraction of Stevia rebaudiana Leaves Using Ultrasound Assisted Extraction Method

Abstract

Stevia rebaudiana has potential to be developed along with the increasing need of national sugar and demand of natural sweetener in Indonesia. Stevia can be an alternative of natural sweetener which is safe for health with the high level of sweetness up to 300 times of cane sugar. Ultrasound-assisted extraction can increase up to 5 times of stevioside concentration in stevia extract compared to extraction without ultrasound. Through this research, the effect of raw material-solvent ratio, amplitude, and extraction time on stevioside concentration, total sugar content, and tannin content were identified in stevia leaves extraction using ultrasound assisted extraction. The process variables in this study were raw material-solvent ratio (1:10, 1:15, 1:20 w/v), amplitude (50%,70%,90%), and time (10,15,20 minutes). Based on the analysis of each variables, best combination of variables was obtained at 1:10 (w/v) of raw material and solvent ratio, 90% of amplitude, and 20 minutes of extraction time with stevioside concentration (29.3% w/v), total sugar content (3.5% w/v), and tannin content (0.4% w/v).

Tanaman Stevia rebaudiana berpotensi untuk dikembangkan seiring dengan peningkatan kebutuhan gula nasional dan permintaan pemanis alami di Indonesia. Stevia dapat menjadi alternatif bahan pemanis alami yang aman untuk kesehatan serta memiliki tingkat kemanisan mencapai 300 kali gula tebu. Ekstraksi dengan bantuan gelombang ultrasonik dapat meningkatkan konsentrasi steviosida pada ekstrak mencapai 5 kali lipat dibandingkan dengan ekstraksi tanpa ultrasonik. Melalui penelitian ini dilakukan identifikasi pengaruh rasio bahan baku-pelarut, amplitudo, dan waktu ekstraksi terhadap konsentrasi steviosida, kadar total gula, dan kadar tanin pada ekstraksi daun stevia menggunakan gelombang ultrasonik. Adapun variabel proses dalam penelitian ini yaitu rasio bahan baku-pelarut (1:10, 1:15, dan 1:20 b/v), amplitudo (50%,70%,90%), dan waktu (10, 15, 20 menit). Berdasarkan analisis terhadap ketiga variabel, diperoleh kombinasi variabel terbaik pada rasio bahan baku-pelarut 1:10 (b/v), amplitudo 90%, waktu ekstraksi 20 menit yang menghasilkan konsentrasi steviosida (29.3% b/v), kadar total gula (3.5% b/v), dan kadar tanin (0.4% b/v).