Modelling of Rehydration Kinetics of Desert Truffles (Terfezia spp.) Dried by Microwave Oven

It is very important to develop a new way of treatment for foodstuffs to provide consumers more chances to choose their foods. In the present study, we aimed to investigate the effect of microwave drying conditions on the rehydration process of Algerian truffles. Previously dried truffles, at different microwave power output (350, 500 and 650 Watt) and weights (100 and 150 g) have been utilized to analyses and to model the rehydration kinetics. Among the six used empirical models, Weibull model has been the most fitted model to all the treated samples. Microwave power output and sample weight were found to have an effect on truffles during drying, and consequently on their rehydration capacity. The high samples amount has decreased the effects of microwave drying by decreasing the density of treatment, also, the high-power output has probably reduced the time of evaporation, and thus more preservation to the dried truffles. These results can be taken into consideration for more industrial applications of microwave drying and subsequent rehydration of truffles.

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Study of color kinetics of banana (Musa cavendish) under microwave drying by application of image analysis

Food Science and Technology International ◽

10.1177/1082013220981334 ◽

2020 ◽

pp. 108201322098133

Author(s):

Sagar Nagvanshi ◽

Subbarao Kotra Venkata ◽

TK Goswami

Keyword(s):

Microwave Power ◽

Vision System ◽

Power Level ◽

Microwave Drying ◽

Slice Thickness ◽

Order Kinetic ◽

Drying Time ◽

Volumetric Heating ◽

Kinetics Of ◽

Microwave Power Level

Microwave drying works on the volumetric heating concept promoted by electromagnetic radiation at 0.915 or 2.450 GHz. In this study, banana ( Musa Cavendish) was taken as the sample and treated under microwave drying. The effect of two process variables, namely slice thickness (2, 3.5, and 5 mm) and microwave power (180 W, 360 W, and 540 W), were studied on drying kinetics and color kinetics. It was observed that the inverse variation relationship exists between drying time and microwave power level while drying time and slice thickness exhibited a direct variation relationship. A Computer Vision System (CVS) was developed to measure the color values of banana in CIELab space using an algorithm written in MATLAB software. Once the color parameters were obtained, they were fitted in First and Zero-order kinetic models. Both models were found to describe the color values adequately. This study concludes that microwave drying is a promising dehydration technique for banana drying that reduces the significant time of drying. Application of CVS is an excellent approach to measure the surface color of banana.

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Drying Properties and Parameters of Blue Honeysuckles Pulp under Foam Assisted Microwave Drying Conditions

International Journal of Food Engineering ◽

10.1515/1556-3758.2540 ◽

2012 ◽

Vol 8 (2) ◽

Cited By ~ 6

Author(s):

Yu Sun ◽

Xianzhe Zheng ◽

Xiangwen Xu ◽

Chenghai Liu ◽

Qiang Li ◽

...

Keyword(s):

Vitamin C ◽

Microwave Power ◽

Influencing Factor ◽

Continuous Production ◽

Microwave Drying ◽

Slow Decline ◽

Power Loading ◽

Three Stages ◽

Drying Properties ◽

Drying Conditions

The drying properties and optimal parameters of foamed blue honeysuckles pulp under microwave drying conditions were studied. The microwave power, loading mass and thickness were selected as the influencing factors, and objective factors were content of anthocyanin, vitamin C, moisture and values of color of the final blue honeysuckles powder. The drying process may be divided into three stages: acceleration stage, slow decline stage and quick decay stage. The initial drying phase lasted until the moisture content was less than 4 kg/kg. The constant drying phase was long when the influencing factor was loading mass. The deceleration drying phase is short in all conditions. This study achieve the continuous production of blue honeysuckles powder and the optimum experiment parameters were obtained as follows, the content of anthocyanin in honeysuckle powder is 64.58 mg/g, the content of vitamin C is 14.604 mg/g, moisture ratio is 9.88 % and the color value is 9.78 with the microwave power at 8.86 kW, loading mass at100 g and the thickness at 4mm.

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Impact of Spouted-Microwave Drying on the Selected Mechanical and Rheological Properties of Zucchini

Agricultural Engineering ◽

10.1515/agriceng-2016-0036 ◽

2016 ◽

Vol 20 (2) ◽

pp. 143-150 ◽

Cited By ~ 1

Author(s):

Bogdan Stępień ◽

Marta Pasławska ◽

Radosław Maślankowski ◽

Mariusz Surma ◽

Klaudiusz Jałoszyński

Keyword(s):

Low Temperature ◽

Product Quality ◽

Rheological Properties ◽

Microwave Power ◽

Raw Material ◽

Microwave Drying ◽

Cutting Resistance ◽

Microwave Assisted ◽

Drying Conditions ◽

Compression Resistance

AbstractMechanical and rheological properties of zucchini dried with spouted microwave - assisted heating was analysed. During spouted drying two levels of microwave power were applied: 100W and 250W. Tests were carried out for the raw material blanched in the temperature of 60ºC for 10 minutes and not subjected to a pretreatment. Compression resistance, cutting resistance and stresses relaxation ratios a and b were determined. A significant impact of drying conditions on the product quality within the scope of mechanical and rheological properties was reported. Raw zucchini has 5 to 7 times higher compression resistance, several times lowered cutting resistance and almost two times higher elasticity in comparison to dried material. Low-temperature blanching significantly affected the values of all investigated properties of dried zucchini. Change in microwave powers during spouted drying significantly influenced the increase of the compression work value.

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Microwave Drying Characteristics and Drying Quality Analysis of Corn in China

Processes ◽

10.3390/pr9091511 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1511

Author(s):

Haili Liu ◽

Haoyu Liu ◽

Heyun Liu ◽

Xu Zhang ◽

Qingchao Hong ◽

...

Keyword(s):

Energy Consumption ◽

Microwave Power ◽

Early Stage ◽

Microwave Drying ◽

Quality Analysis ◽

Drying Rate ◽

Drying Characteristics ◽

Drying Conditions ◽

Opposite Tendency

To identify the microwave drying characteristics of corn, microwave drying tests were conducted on corn. By taking the moisture content, drying rate, and drying temperature as indices, this research revealed the effects of different microwave powers and loads on the microwave drying characteristics of corn. Moreover, energy consumption and quality of dried corn were analysed under different drying conditions. The results demonstrate that microwave drying has significant energy-saving effects. The energy consumption by microwave drying is less than 0.3 times that used by electrothermal drying under the same load. Both microwave power and load exert significant influences on drying characteristics. Higher microwave power results in a greater average drying rate, wherein shorter periods of time are required to reach the maximum drying rate and higher temperatures of the corn. However, the load shows the opposite tendency. The smaller the load, the higher the temperature of the corn in the early stage of drying. However, as drying continues, the temperature curve changes significantly, and the temperature rises with the increase in load in the later stage of drying. In consideration of energy consumption and dried quality, the load of corn should be increased as appropriate, and the microwave intensity should be limited to no higher than 0.7 W/g in the experiment.

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Microwave drying behaviour of tomato slices

Czech Journal of Food Sciences ◽

10.17221/30/2012-cjfs ◽

2013 ◽

Vol 31 (No. 2) ◽

pp. 132-138 ◽

Cited By ~ 7

Author(s):

S. Çelen ◽

K. Kahveci

Keyword(s):

Energy Consumption ◽

Theoretical Model ◽

Microwave Power ◽

Internal Heat ◽

Internal Heat Source ◽

Microwave Drying ◽

Drying Rate ◽

Drying Time ◽

Drying Behaviour ◽

Drying Conditions

The microwave drying behaviour of tomato slices was investigated experimentally to determine the effects of microwave power on the drying rate, energy consumption, and dried product quality in terms of colour, and a theoretical model was proposed to define the drying curves of tomato slices. The experiments performed with the microwave power of 90, 180, 360, and 600 W indicate that the drying time and the energy consumption decreased considerably with an increase in microwave power. The experiments also revealed that the drying rate shows first an increase and then a decrease during drying, and that the colour quality of the product deteriorates significantly with the increase of the microwave power. A theoretical model was developed using the solution of energy equation considering the microwave power as an internal heat source. The electric field strength inside the material was assumed to be dependent on the moisture content and the constants emerging from this assumption were obtained by minimising the sum of squared differences between the theoretical results and experimental data obtained for various drying conditions. The results show that the values proposed for the constants provide a good agreement between the theoretical and experimental drying behaviour.  

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Rechargeable lithium battery for use in applications requiring a low to high power output

Journal of Power Sources ◽

10.1016/s0378-7753(97)84026-8 ◽

1998 ◽

Vol 70 (1) ◽

pp. 140

Author(s):

J Bates

Keyword(s):

High Power ◽

Power Output ◽

Lithium Battery ◽

Rechargeable Lithium Battery ◽

High Power Output

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Polyelectrolyte Gels: A Unique Class of Soft Materials

Gels ◽

10.3390/gels7030102 ◽

2021 ◽

Vol 7 (3) ◽

pp. 102

Author(s):

Ferenc Horkay

Keyword(s):

Exchange Process ◽

Interaction Strength ◽

Soft Materials ◽

Industrial Applications ◽

Future Research ◽

Swelling Kinetics ◽

Polyelectrolyte Gels ◽

Ion Exchange Process ◽

Counter Ions ◽

Kinetics Of

The objective of this article is to introduce the readers to the field of polyelectrolyte gels. These materials are common in living systems and have great importance in many biomedical and industrial applications. In the first part of this paper, we briefly review some characteristic properties of polymer gels with an emphasis on the unique features of this type of soft material. Unsolved problems and possible future research directions are highlighted. In the second part, we focus on the typical behavior of polyelectrolyte gels. Many biological materials (e.g., tissues) are charged (mainly anionic) polyelectrolyte gels. Examples are shown to illustrate the effect of counter-ions on the osmotic swelling behavior and the kinetics of the swelling of model polyelectrolyte gels. These systems exhibit a volume transition as the concentration of higher valence counter-ions is gradually increased in the equilibrium bath. A hierarchy is established in the interaction strength between the cations and charged polymer molecules according to the chemical group to which the ions belong. The swelling kinetics of sodium polyacrylate hydrogels is investigated in NaCl solutions and in solutions containing both NaCl and CaCl2. In the presence of higher valence counter-ions, the swelling/shrinking behavior of these gels is governed by the diffusion of free ions in the swollen network, the ion exchange process and the coexistence of swollen and collapsed states.

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