The impact of periodic operation on barley hydration

Abstract

Intensification 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 (K SPER15-30 = 0.55 cm h −1 ) obtained by the Omoto-Jorge model was higher than that observed for the isothermal hydration (K SISO = 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.

Moisture diffusivity, hardness, gelatinization temperature, and thermodynamic properties of ultrasound assisted soaking process of cowpea

“…An analytical solution of Equation (4) can be obtained by adopting the assumptions that cowpea grain is spherical, diffusivity coefficient does not depend on moisture concentration, seed volume change during hydration is negligible, the surface film resistance against water transfer is negligible, the surface instantaneously reaches equilibrium moisture, the process is only controlled by the diffusion mechanism (Crank, 1979). For long soaking times, only the first term of series equation (Equation (4)) was significant (Chacón Alvarez et al,2020; Mayolle, Lullien‐Pellerin, Corbineau, Boivin, & Guillard, 2012; Yildirim et al, 2011). Simplifying this by taking the first term of the series solution, gives Equation (5) (Sabapathy, Tabil, & Baik, 2005; Sayar, Turhan, & Gunasekaran, 2001).…”

“…The cowpeas water absorption data was fitted using Fick's second diffusion model (Equation (4)) (Chacón Alvarez, Jorge, & Jorge, 2020; Crank, 1979; Wambura, Yang, & Wang, 2008; Yildirim et al, 2011). where n is the positive integer, D eff is the effective moisture diffusivity coefficient (m 2 s −1 ), t is the soaking time (s) and R e is the average radius of cowpea (m).…”

Influence of temperature, ultrasound, and variety on moisture diffusivity and thermodynamic properties of some durum wheat varieties during hydration

“…The mathematical mechanisms for the kinetics of the moisture diffusion process of different agricultural products have been proposed for the second Fick's diffusion model by some researchers previously (Abbaspour-Gilandeh et al, 2019;Balbinoti et al, 2018aBalbinoti et al, , 2018bChacon Alvarez et al, 2020;Jahanbakhshi et al, 2020;Kumar et al, 2021;Mattioda et al, 2018;Ulloa et al, 2015). Assuming that in the process of hydration of wheat kernels, the D eff is constant and radial, its amount can be obtained through Equation ( 5) (Abbaspour-Gilandeh et al, 2019;Jafarifar et al, 2017;Jahanbakhshi et al, 2020).…”

“…It is essential to understand mechanism of water absorption process of agricultural products and its effects on subsequent operations and quality of final product (Guimaraes et al, 2020; Li & Jiang, 2016; Mattioda et al, 2018; Shafaei et al, 2016; Yildirim, 2017). The diffusion model is a phenomenological model, which allows relating experimental data to the laws of physics, and has been fitted to the experimental data of hydration and dehydration of agricultural products (Abbaspour‐Gilandeh et al, 2019; Balbinoti et al, 2018a, 2018b; Chacon Alvarez et al, 2020; Jahanbakhshi et al, 2020; Kumar et al, 2021; Patero & Augusto, 2015; Ulloa et al, 2015).…”

Periodic operation as an alternative to intensify the hydration process of common beans (Phaseolus vulgaris)

“…This type of operation has already been shown to be a viable alternative for intensifying the hydration of grains, although currently, it is addressed in only a few studies in the literature. The works involving the periodic hydration process that were found in the literature include studies involving wheat (Mattioda et al, 2018, 2019b), barley (Chacón Alvarez et al, 2020), and triticale (Oliveira et al, 2020). These studies show that this operation can be more advantageous as compared to conventional (isothermal) hydration, since it intensified both the mass transfer and energy of the process.…”