Optimalisasi Kondisi Proses Fermentasi Yoghurt Sinbiotik dengan Penambahan Maltooligosakarida dari Ubi Jalar Ungu Sebagai Pangan Fungsional Preventif Diabetes

Abstract

Indonesia ranks fifth among countries with the highest number of diabetes cases worldwide, highlighting the urgent need for effective solutions. One potential strategy is the development of functional food innovations utilizing local commodities, such as the Ayamurasaki purple sweet potato variety from North Sumatra. This study was aimed to determine the optimal fermentation conditions for synbiotic yoghurt with the addition of maltooligosaccharides from purple sweet potato, as well as to evaluate its antidiabetic activity both in vitro and in vivo. The method used in this research was Response Surface Methodology–Box Behnken Design (RSM-BBD) with Design Expert v.13 software. The research analyzed the responses based on three factors: the percentage of maltooligosaccharide addition (0–10%), the concentration of lactic acid bacteria (LAB) starter culture (1–5%), and the fermentation time (4–8 hours), formulated into 17 experimental conditions. The results showed that the percentage of maltooligosaccharide addition, LAB starter concentration, and fermentation time were significantly (P<0.05) affected the pH, total acidity, total sugar content, antioxidant activity, total lactic acid bacteria count, viscosity, and viscosity hedonic score. Optimization results indicated that the ideal fermentation conditions to be 10% purple sweet potato maltooligosaccharide addition, 1,647% LAB starter concentration, and 6,488 hours of fermentation, with a desirability value of 0,865. Synbiotic yoghurt fermented under these optimal conditions showed an α-amylase enzyme inhibition of 51.5607%. In vivo evaluation on streptozotocin-induced diabetic rats showed that treatment a diet composed of 50% synbiotic yogurt and 50% standard feed reduced blood glucose levels by up to 68,01%, maintained body weight, and improved pancreatic beta-cell integrity. The Kruskal-Wallis test showed no significant effect (P>0.05) between the synbiotic yogurt treatment and the administration of metformin at a dose of 150 mg/kg body weight.