The impact of periodic operation on barley hydration

Abstract

AbstractIntensification of barley hydration process using periodic operation was evaluated as compared to isothermal hydration conditions (20°C). Periodic operation resulted in an 82.88% saving in time, and consequently, energy. The Peleg model exhibited satisfactory fit to the experimental data for the hydration kinetics. The mass transfer coefficient of the periodic operation (KSPER15‐30 = 0.55 cm h−1) obtained by the Omoto‐Jorge model was higher than that observed for the isothermal hydration (KSISO = 0.42 cm h−1); the hydration rate was increased by 31% for an amplitude of 15°C and a period of 30 min. The isothermal diffusion coefficient presented a value of 68.31 × 10−12 m s−2 and a periodic diffusion coefficient of 78.61 × 10−12 m s−2 for the hydration process. The intensification of the hydration process because of the periodic operation did not negatively affect the energy and germination index of the barley grains.Practical ApplicationsThe present work describes the impact of periodic operation on barley hydration. This mode of operation may be applied practically as a new process intensification strategy for the brewing industry. Periodic operation proved to be more efficient than the conventional process, resulting in faster water absorption rates and a shorter hydration time; consequently, a lower amount of energy is required for the hydration process. Since the grain germination index and germination energy remained unchanged as compared to the conventional process, periodic operation appears to be a very promising technology for malt production. The mathematical models obtained adequately described the behavior of the hydration kinetics and allowed the mass transfer coefficient to be evaluated; thus, they may be used in the project, optimization and simulation of the process.