PRODUKSI LOW CALORIE SWEET BIO-YOGHURT DENGAN PENAMBAHAN EKSTRAK DAUN STEVIA (Stevia rebaudiana) SEBAGAI PENGGANTI GULA (Production of Low Calorie Sweet Bio-Yoghurt with The Addition of Stevia’s Leaf Extract (Stevia rebaudiana) for Sugar Substitution)

Abstract

The purpose of this study was to examine potential utilization of stevia’s leaf as sugar substitute in low calorie sweetbio-yoghurt. The experiment was carried out with the supplementation of stevia’s leaf extract in yoghurt at level 0.5; 2.0; 3.5% and yoghurt produced with supplementation 7.0% sugar used as a control. Parameters observed were level of stevioside, calorie content, pH and acidity, total solid, nutritional composition, microbiological quality, and sensory acceptance. The result showed that level of stevioside obtained in ethanol phase was higher (12.73%) than that in butanol phase (11.89%). There were no differences on pH and acidity in yoghurt either supplemented with sugar or stevia’s leaf extract. The protein content in yoghurt supplemented with stevia’s leaf extract was higher than that supplemented with sugar, but no differences were observed on lactose content. Supplementation of stevia’s leaf extract at 0.5% increased fat content, but higher level of supplementation (2.0 and 3.5%) had no effects on fat content. Calorie content of yoghurt supplemented with stevia’s leaf extract was lower than that supplemented with sugar. The supplementation of stevia’s leaf extract in yoghurt affected on taste, flavor, mouth-feel, and acceptance but had no effect on appearance and colour. Stevia’s leaf extract was able to maintain viability of lactic acid bacteria and probiotic kept for a week in a refrigerator. Low calorie sweet bio-yoghurt with supplementation of stevia’s leaf extract at level 0.5% had the highest acceptance/ Keywords: Low calorie sweet bio-yoghurt, stevia leaf, sugar substitute ABSTRAK Penelitian ini bertujuan untuk mengkaji pemanfaatan stevioside hasil ekstraksi daun stevia (Stevia rebaudiana) sebagai pengganti gula dalam produk low calorie sweet bio-yoghurt. Penelitian dilakukan dengan penambahan 0,5; 2,0 dan 3,5% ekstrak daun stevia pada yoghurt dan sebagai kontrol yoghurt dengan penambahan 7,0% gula. Parameter yang diamati adalah kadar stevioside hasil ekstraksi, kandungan kalori, nilai pH dan keasaman, komposisi nutrisi, kualitas mikrobiologis, serta sensoris produk yoghurt. Hasil penelitian menunjukkan kadar stevioside hasil ekstraksi fase etanol (12,73%) lebih tinggi dibandingkan fase butanol (11,89%). Tidak ada pengaruh antara sweetener gula dengan ekstrak daun stevia terhadap nilai pH dan keasaman yoghurt. Penambahan sweetener gula dan ekstrak daun stevia sebesar 0,5; 2,0; dan 3,5% meningkatkan kandungan protein, tetapi tidak berpegaruh terhadap kandungan laktosa yoghurt. Penambahan ekstrak daun stevia 0,5% meningkatkan kadar lemak, tetapi penambahan lebih tinggi (0,5 dan 3,5%) tidak berpengaruh terhadap kadar lemak yoghurt. Nilai kalori yoghurt dengan penambahan ekstrak daun stevia lebih rendah dibandingkan dengan penambahan gula. Hasil pengujian kualitas sensoris menunjukkan tidak ada perbedaan penampilan dan warna antara yoghurt dengan penambahan sweetener gula dibandingkan dengan ekstrak daun stevia, tetapi penambahan ekstrak daun stevia berpengaruh terhadap aroma, rasa, mouth-feel, dan daya terima. Penambahan ekstrak daun stevia dapat mempertahankan viabilitas bakteri asam laktat dan probiotik dalam yoghurt selama seminggu. Low calorie sweet bio-yoghurt dengan penambahan 0,5% ekstrak daun stevia menghasilkan daya terima terbaik bagi panelis. Kata kunci: Low calorie sweet bio-yoghurt, daun stevia, pengganti gula