Showing papers in "Journal of Food Engineering in 1999"

TL;DR: In this article, the importance of T-g in relation to drying process and dried foods is discussed, which results in an increased rate of physicochemical changes in dried products, such as sticking, collapse, caking, agglomeration, crystallization, loss of volatiles, browning and oxidation.

TL;DR: In this article, the thin layer drying characteristics of hazelnuts during roasting were described for a temperature range of 100-160°C, using five semi-theoretical and two empirical thin layer models.

TL;DR: In this article, the authors identify the kinetics of drying of dehydrated agricultural products, such as high-sugar containing fruits, as well as a decomposition reaction of the constituents of the fruits such as sugars.

TL;DR: In this paper, the authors present a characterisation of the flow properties of four food powders (flour, skim-milk, tea and whey-permeate) using an annular shear cell.

TL;DR: In this article, the authors used peach puree as a model food to further validate calculated optimal conditions, isothermal experiments were performed between 110°C and 135°C, and colour was quantified using the L, a, b system.

TL;DR: In this article, a batch-type experimental dryer with an online weighing mechanism was developed for determining the thin-layer drying behavior of onion slices, and the experimental data obtained were fitted into an Arrhenius-type model and power model using non-linear regression analysis.

TL;DR: In this paper, a laboratory MW/vacuum drier was used for drying kinetics experiments with model fruit gels, simulating orange juice concentrate, and an empirical model was proposed for estimating the drying constant (K ) as a function of the absolute pressure and the MW power of the system.

TL;DR: In this article, the effect of thermal treatments on 11°Brix pear puree was studied at temperatures from 80°C to 98°C, and a two-stage mechanism was applied to the changes in colour difference and a *.

TL;DR: In this paper, a change in the slope of the curve giving the maximum of consistency is observed at a typical water content, due to the presence of excess free water in industrial soft wheat flour.

TL;DR: In this paper, the influence of relative humidity and temperature on the flowability of the following food powders: flour, tea and whey permeate were evaluated using an annular shear cell.

TL;DR: Ohmic pretreatment of fruit and vegetable samples has been shown to increase hot-air drying rate, shift desorption isotherms, and increase juice yields over raw samples or those pretreated with conventional or microwave heating as mentioned in this paper.

TL;DR: In this article, selected properties of African breadfruit seeds namely seed size, shape, gravimetric composition, density characteristics (physical), dynamic angle of repose, static coefficient of friction (mechanical) and suspension velocity (aerodynamic) were determined.

TL;DR: In this paper, the effect of various dipping pretreatments on drying kinetics of grapes under warm air convective drying conditions has been studied, and a dryer was built to perform the experiment under controlled condition of drying air at temperature 60°C and velocity 0.5 m/s.

TL;DR: In this paper, the effect of ultra-high hydrostatic pressure on selected hydrosoluble vitamins (B1, B6 and C) was studied under current operating parameters for the above processes.

TL;DR: In this paper, a conical, counter-rotating twin-screw extruder was used to extrusion maize grits at different barrel temperatures (140-180°C), feed moistures (13-17% wet basis), feed rates (38-52 kg/h), and screw speeds (60-80 rpm).

TL;DR: In this paper, the authors simulated natural convection heating within a can of liquid food during sterilization by solving the governing equations for continuity, momentum and energy conservation for an axisymmetric case using a commercial Computational Fluid Dynamics (CFD) package.

TL;DR: In this paper, the compressive engineering stress (σE)-strain (eE) relationship up to rupture of several mannuronic and guluronic alginate gels was studied by varying the alginates effective concentration (ceff) from 0.8 to 1.7% w/w and was correlated by using the power model.

TL;DR: In this paper, the authors used far infrared radiation to enhance the drying rate and reduce the energy consumption of barley in thin layers both under combined FIR-convection and convection alone.

TL;DR: In this paper, the effect of a high-rate enzymatic treatment for the degradation of suspended solids was assessed, resulting in the selection of a commercial enzyme preparation, which could be recycled in order to use its residual enzyme activity.

TL;DR: In this paper, a model for simultaneous heat, water and vapour diffusion was developed to use for prediction of the diffusion of water inside foods during heat processing, based on Fourier's and Fick's Laws.

TL;DR: In this paper, the effect of wall shear stress, emulsifier concentration and membrane pore size on the formation of small emulsion droplets was investigated and it was found that small size is important for emulsion stability.

TL;DR: The viscosity property of seven varieties of commercial Australian honeys (yellow box, tea tree, leatherwood, red gum, iron bark, strawberry clover and creamed) was analysed over a range of temperatures (4-30 degrees C).

TL;DR: In this article, it was found that ice crystallisation within the freezer is dominated by recrystallisation processes such as aggregation and dissolution/growth, which are more important than nucleation in determining the final crystal population.

TL;DR: In this paper, an unconfined yield test was used to measure the cohesion of dairy powders to determine the influence of powder composition, temperature, moisture content and particle size.

TL;DR: In this paper, a drying model, named NIZO-DrySim, is developed to simulate aspects of drying processes in the food industry, which makes use of computational fluid dynamics (CFD) techniques.

TL;DR: In this article, the combined effect of high power ultrasound and temperature on the activity of peroxidase type VI from horseradish suspended in water was studied, and it was found that the decimal reduction time of peroxideidase at 80°C, D80, reduces from 65 to 10 min ca. when ultrasound are applied.

TL;DR: In this paper, a model for the growth of a single gas bubble as a result of the generation of carbon dioxide and water vapour from the surrounding viscous dough is considered.

TL;DR: In this article, a moving boundary diffusion model was used to predict drying curves for dehydrating prunes (Prunus Domestica), which is a numerical solution based on Fick's Second Law and takes into account shrinkage of the fruit during the process.

TL;DR: In this article, the physical and sensorial properties of strawberry jams using fruit dietary fibre (DF) as a stabiliser were evaluated and compared with those made with a commercial thickener. Strawberry jams of up to 55 °Brix were obtained from the total or partial substitution of commercial amidade pectin by peach DF in a standard formulation.

TL;DR: In this paper, the effectiveness of high intensity ultrasound for thawing frozen foods was evaluated on frozen meat and fish samples, and it was found that ultrasonic absorption is greatest near the initial freezing point where most of the freezing occurs, and overheating near the surface was a problem at high intensities and at high and low frequencies, due to the increase in attenuation with frequency, and the onset of cavitation at low frequencies.