Abstract:
Finger millet is cereal crop grow in diverse agro-climatic conditions. In African countries, among others uses malted millet to brew various traditional beers. In Ethiopia, it is used as the most important ingredient to make a traditional opaque beer called tella and katicalla/areke. Its malt has also a great potential to be used in brewing commercial beer. But the malting conditions play a significant role to produce different finger millet based products. This research was aimed to study the effect of germination temperature, germination day, and curing temperature on the quality attributes of malt and beer. This study was conducted in factorial design arranged in completely randomized design with three replications. The factors considered were germination temperature (20°C, 25 °C and 30 °C), germination time (2, 3, and 4 days) and curing temperatures (70 °C, 80 °C, and 90 °C). The grain, malt, and beer quality parameters were analyzed to see the effect of these factors on the quality attributes of finger millet malt and beer using a standard methods. The collected data were subjected to statistical analysis using SAS software. Most of the malt and beer quality parameters were significant among germination temperature, germination time and curing temperature. Some of the malt and beer quality parameters such as total protein content, hot water extract, degree Plato, wort viscosity, wort color, wort pH, total phenol, calcium content, FAN, beer alcohol content and degree of fermentability were ranged from 6.45 - 8.32%, 77.6 - 90.72%, 8.7 - 9.9 % plato, 1.49 - 1.79 cP, 3.35- 4.63 EBC, 5.86 - 6.45, 1.25-1.63 mgGAE/100g, 162- 487mg/100g, 117- 133 mg/L, 3.3 - 4.70 %, and 71.48 - 82.08% , respectively. Malt sample germinated at 30°C for 4 days and cured at 70°C shown the maximum value (70.07 WK units) of diastatic power. The highest hot water extract (90.72%) was obtained in a malt sample germinated at 25 °C for 4 day and cured at 70 °C. The lower curing temperature ( 70 °C) had given the highest diastatic power and hot water extract. The lowest value (1.49 cp) of wort viscosity was found at malt sample germinated at 20 °C for 4 days and cured at 80°C. Higher wort color was obtained at more modified malt, because of browning reaction between amino acids and simple sugur. The sensory analysis revealed that the most accepted beers interms of sweetness, body, mouthfeel, & overall acceptability were obtained from the malt samples germinated at 30 °C for 4 days & cured at 90°C. Most of the values or results found were within the acceptable limit of EBC.
Keyword: Germination Temperature, Germination Time, Curing Temperature, Finger Millet, Malt Quality, Beer