Modeling the hydration of foodstuffs: Temperature effects

Abstract

To assess the impact of hydration kinetics of dried foodstuffs on their

Porous media approaches to studying simultaneous heat and mass transfer in food processes. I: Problem formulations

“…Washing of solutes in a packed bed of tea leaf in teabag infusion is studied using this porous medium formulation (Lian & Astill, 2002). Rehydration of tea leaves was studied (Weerts, Lian, & Martin, 2003a;Weerts, Lian, & Martin, 2003b) that included the effect of anisotropy of the microstructure and temperature. Study of rehydration in other materials using similar formulation has also been proposed by Saguy, Marabi, and Wallach (2005).…”

Kinetics of water absorption and solute leaching during soaking of breakfast cereals

“…Not only can the number of water protons in the rehydrating food pieces be deduced from the changing amplitude of the NMR signal (Gruwel et al, 2001;Weerts et al, 2003), but changes in molecular structure under the hydration process can be monitored through the changing relaxation times (Schuck et al, 2002). The attribution of NMR signal amplitude to the different water compartments has often been assumed in previous studies, and the behaviour of the non-aqueous protons and their contribution to the liquid signal have not to our knowledge been assessed, and the results obtained with the NMR method have not been compared with those of conventional separation techniques.…”

“…The 1 H nuclear magnetic resonance (NMR) technique has been adapted to continuous monitoring of water absorption during soaking and has already been applied to a certain range of food products, e.g., leaf tea (Weerts, Lian, & Martin, 2003), seeds (Brosio, Di Nola, & Verzegnassi, 1993), barley kernels (Gruwel, Chatson, Yin, & Abrams, 2001), corn flakes (Cornillon & Salim, 2000), and milk powder (Davenel, Schuck, & Marchal, 1997;Schuck et al, 2002). Not only can the number of water protons in the rehydrating food pieces be deduced from the changing amplitude of the NMR signal (Gruwel et al, 2001;Weerts et al, 2003), but changes in molecular structure under the hydration process can be monitored through the changing relaxation times (Schuck et al, 2002).…”

Effect of porosity on rehydration of dry food particulates

“…5 A different approach for exploring the rehydration mechanism of a porous biomaterial (black leaf tea) was proposed recently, utilizing the capillary flow theory. 13,14 One of the main advantages of this approach is that the constitutive relationships required to solve the capillary flow equations are formulated from physical principles and are based on water activity curves, commonly used by food science and engineering practitioners. It is worth noting that the capillary imbibition theory is well developed and widely applied in many other fields (eg soil science, 15 oil recovery, 16 printing 17 ).…”