Eduardo, Ojito (Prof.)Gebreselassie, Gebregziabiher2020-03-082023-11-102020-03-082023-11-102019-11-08http://etd.aau.edu.et/handle/12345678/20989Sweet potato is one of the largest sources of starch. Due to this fact, it can be utilized to obtain value-added products. This research aims at producing glucose syrup from sweet potato using acid hydrolysis and preservation using potassium sorbate. Starch was isolated by using distilled water. The maximum yield of starch was found to be 31.59%. Work was therefore undertaken to obtain glucose syrup by hydrolyzing starch with a sulfuric acid concentration of (0.5, 1, and 1.5%) at temperatures (130, 140 and 150 °C) and times (25, 30 and 35 min). The total reducing sugar content of the hydrolysates produced was determined using the dinitro salicylic acid method and the maximum reducing sugar was found to be 241 g/L at 1 % sulfuric acid concentration, 140 °C and 30 minutes. The moisture content, dry matter, ash content, density, viscosity and pH of the product were determined and they were found to be 26%, 74% 0.26%, 1.37 g/mL, 5.63 and 4.9 respectively. Design-Expert software version 11 using Box-Behnken design was used for statistical assessment to identify the important parameters for glucose syrup production. The results of the statistical analysis showed that all the three main factors had a significant positive effect on glucose syrup yield. Since glucose syrup is perishable and degradable which has a short shelf life during storage, potassium sorbate was used to prolong its shelf-life. The effect of potassium sorbate with having concentrations of 0, 0.025, 0.05, 0.075, and 0.1% were studied for 60 days to sustain the shelf life of glucose syrup by studying its effects on the physio chemical properties. Potassium sorbate concentration 0.05% which is within permitted level, was identified as a suitable preservative to retain the quality and extend the shelf-life glucose syrup at room temperature.en-USSweet potato, Starch, Acid hydrolysis, Glucose syrup, PreservationThesis