Pengaruh Konsentrasi Gula dan Ragi Dalam Pembuatan Cuka Dari Rosella (Hibiscus sabdariffa.L) Terhadap Mutu Cuka Rosella - Firdausni, Firdausni (Institution for Industrial Research and Standardization of Industry - Padang, 2013)
Rosellla (Hibiscus sabdariffa.L) has been traditionally used as nutritious functional beverages. Rosella flowers contain flavonoid secondary metabolites, terpenoids, and vitamin C, which are considered as antioxidant. Research aims to see the effect of sugar and yeastÂ on quality of vinegar. The study was conducted with the treatment of sugar utilization (10, 15, 20, 25) %, fermentation with yeast Saccharomyces cerevisiae (2, 4, 6) g and fermentation time until three weeks. Rosella vinegar as a results of fermentation further was analyzed the pH, acetic acid content, extract content and antioxidant activity test consisted of qualitative test of phenolic, flavonoid, and % inhibition. Result of the optimal research was obtained in the treatment of sugar utilization 20% and the addition of yeast 6 g with analysis result of pH 2.67, acetic acid 14.80%, extract content 7.15%, and % inhibition 31%, moreover it contained phenolic and flavonoidscompounds qalitatively.ABSTRAKRosellla (Hibiscus sabdariffa.L) telah digunakan secara tradisional sebagai minuman yang berkhasiat fungsional. Bunga rosella mengandung flavonoid metabolit sekunder, terpenoid, dan vitamin C yang berfungsi sebagai antioksidan. Penelitian ini bertujuan untuk melihat pengaruh pemakaian gula dan ragiÂ terhadap mutu cuka. Penelitian dilakukan dengan perlakuan penggunaan gula pasir (10, 15, 20, 25) %, fermentasi dengan ragi Saccharomyces cerevisiae (2, 4, 6) g dan waktu fermentasiÂ sampai tiga minggu. Hasil fermentasi berupa cuka rosella selanjutnya diuji pH, kandungan asam asetat, kadar sari dan uji aktifitas antioksidan yang terdiri dari uji kualitatif fenolik, flavonoid, dan % inhibisi. Hasil penelitian optimal diperoleh pada perlakuan penggunaan gula 20% dan penambahan ragi 6 g dengan hasil analisis pH 2,67, asam asetat 14,80%, kadar sari 7,15% dan % inhibisi 31% serta secara kualitatif mengandung senyawaan fenolik dan flavonoid.