Pengaruh Penggunaan Ragi Alami (Sourdough Starter) terhadap Mutu Organoleptik, Mutu Kimia, Mutu Fungsional, Nilai Energi, dan Indeks Glikemik Roti Tawar Substitusi Puree Ubi Jalar Ungu (Ipomoea Batatas L) bagi Penderita Diabetes Melitus Tipe 2

Type 2 Diabetes Meitus (T2DM) is a chronic disease with the prevalence of sufferers that continues to increase every year and can cause complications and even death. T2DM management can be done through nutritional therapy, education, physical activity, and pharmacology. One form of nutritional therapy is to do 3J, namely the right schedule, type, and amount in DM patients. The right type can be done by choosing foods with a low to moderate glycemic index so that people with diabetes can control their blood glucose levels. The purpose of this study was to determine and analyze the effect of using natural yeast (sourdough starter) on chemical quality (moisture content, ash content, and carbohydrates), functional quality, namely resistant starch fiber, glycemic index, energy value, and organoleptic quality (taste, color, texture, and aroma) in white bread substituted with purple sweet potato for patients with type 2 diabetes. This type of research was experimental Completely Randomized Design (CRD) using 3 levels of treatment with natural yeast percentages of 30%, 40%, and 50% with the addition of purple sweet potato (Ipomoea Batatas L.) as much as 40%. The results showed that natural yeast (sourdough starter) had a significant effect (p<0.05) on chemical and functional quality, namely water content, ash content, carbohydrates, and resistant starch as well as on organoleptic quality of taste, color, and aroma. Chemical quality, namely carbohydrate content meets the 2015 PERKENI dietary standards (45 – 65%) and the functional quality of resistant crate fiber also meets the 2015 PERKENI dietary standards (20 – 35 grams/day). The water content and ash content have met SNI 01-3840-1995 for white bread standards. The best treatment has glycemic index 71 was at the level of treatment P2 with the highest yield value (Nh) 0.81 . Keyword: Type 2 Diabetes Meitus, Bread, Natural yeast, Glycemic index