Effect of Steeping and Germination Time on Some Physicochemical Properties of Rye Malt with Using the Response Surface Methodology

Malting involves steeping, germination and drying of green malt in controlled conditions of temperature and humidity. The purpose of this study was to investigate some of the physicochemical properties of rye malt, including malting efficiency, 1000 seeds weight, mass density, hot water extract efficiency and Kolbach index under the influence of time of soaking and germination. To evaluate these parameters and to prepare malt, 3 steeping periods (24, 36 and 48 hours) and 3 germination times (5, 7 and 9 days) were used. Statistical analysis and process optimization were performed using the Surface methodology. The results showed that increasing the duration of soaking and germination, the malt efficiency, 1000 seeds weight and density decreased, but the efficiency of the hot water extract and the Kolbach index increased and according to the results of process optimization, it can be stated that the application of conditions was 42.7 hours steeping and 9-day germination resulted in the best quality malt extract in terms of malt efficiency and hot water extract and Kolbach index. a