scholarly journals Studies on the Effect of Mass Transfer in Vacuum Impregnation on the Bioactive Potential of Apples

Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3533 ◽  
Author(s):  
Marta Pasławska ◽  
Bogdan Stępień ◽  
Agnieszka Nawirska-Olszańska ◽  
Kinga Sala
Keyword(s):  
Mass Transfer ◽  
Antioxidant Capacity ◽  
Vacuum Impregnation ◽  
Process Conditions ◽  
Mass Variation ◽  
Polyphenol Content ◽  
Solid Gain ◽  
Vacuum Level ◽  
Apple Tissue ◽  
Bioactive Potential

The purpose of the study was to evaluate the efficiency of mass transfer during vacuum impregnation (VI) of apple tissue by different process conditions. VI was carried out in two stages: Vacuum (4, 6, or 8 kPa maintained at time 10, 20, 30, 40, 60, and 80 s) and atmospheric (4 min under atmospheric pressure). As infiltration liquids, fresh squeezed apple-pear juice (J), 3% citric acid solution (C), and distilled water (DW) were used. Mass transfer was analyzed based on three factors: Mass variation (MV), dry mass variation (DMV), and solid gain (SG). The outflow of native components and inflow of infiltration liquid has been described by mathematical models. The polyphenol content and antioxidant capacity (ABTS+, FRAP) were evaluated as the bioactive potential factors confirming native component outflow and incorporation of liquid molecules into an apple tissue. It was found that during VI of an apple tissue, intensive mass transfer occurred: Native components of fruit tissue outflowed and external ingredients of impregnation liquid inflowed into the material with the intensity proportional to the vacuum level and process time. The most beneficial conditions of apple cube VI were noticed at a vacuum level of 4 kPa for a minimum of 40 s, which is when the highest polyphenol content and antioxidant capacity occurred.

scholarly journals Ohmic heating/vacuum impregnation treatments on osmodehydrated apples enriched in polyphenols from concentrated pomegranate juice

2018 ◽  
Author(s):  
Jorge Moreno ◽  
P. Zúñiga ◽  
M. E. Guerra ◽  
K. Mella
Keyword(s):  
Mass Transfer ◽  
Electric Field ◽  
Water Content ◽  
Ohmic Heating ◽  
Pomegranate Juice ◽  
Vacuum Impregnation ◽  
Polyphenol Content ◽  
Osmotic Treatment ◽  
Reduced Water ◽  
Improve Mass Transfer

The aim of this work was to study the combination of osmodehydration (OD), coupled with Ohmic Heating (OH) and Pulsed Vacuum (PV) and to introduce natural compounds from a cryoconcentrated pomegranate juice (47°Brix) at 30, 40 and 50 °C into apple matrix, during 180 min. PV was performed at 50 mbar for 5 min at the beginning of the process and OH generates an electric field of 6.6 V/cm. The results indicated that treatments reduced water content and increase polyphenol content of apples, evidencing that the osmotic treatment improve mass transfer, especially when they are applied together at higher temperatures. Keywords: Ohmic heating; pulsed vacuum; cryoconcentration; enriched; pomegranate.

scholarly journals The Effect of Mechanical Vibration during Transport under Model Conditions on the Shelf-Life, Quality and Physico-Chemical Parameters of Four Apple Cultivars

Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 81
Author(s):  
Dorota Walkowiak-Tomczak ◽  
Natalia Idaszewska ◽  
Grzegorz P. Łysiak ◽  
Krzysztof Bieńczak
Keyword(s):  
Antioxidant Capacity ◽  
Dry Matter ◽  
Mechanical Vibration ◽  
Life Quality ◽  
Titratable Acidity ◽  
Quality Parameters ◽  
Soluble Solids ◽  
Chemical Parameters ◽  
Polyphenol Content ◽  
Flesh Colour

The study assessed the changes in the quality and physical and chemical parameters of apples of four cultivars (‘Gala’, ‘Idared’, ‘Topaz’, ‘Red Prince’) subjected to mechanical vibration during transport under model conditions and after storage (shelf-life). Quality changes in apples were evaluated based on skin and flesh colour, total soluble solids, dry matter, firmness, titratable acidity, pH value, total polyphenol content, and antioxidant capacity. The vibration applied at a frequency of 28 Hz caused changes in the above parameters, which were visible also after storage and depended on the cultivar, but often did not show any clear trend or direction or were not statistically significant. The values of the total colour difference factor ΔE showed considerable variations in the skin colour but only small variations in the flesh colour of individual cultivars. Vibration resulted in a decrease in firmness. Variations in dry matter, total soluble solids, pH, and titratable acidity were small, often insignificant. Mechanical vibration and storage led to an increase in the polyphenol content and antioxidant capacity of all studied cultivars. The greatest stability of quality parameters, relatively high content of bioactive compounds, and antioxidant capacity were observed for ‘Red Prince’. The lowest quality parameters were noted for ‘Gala’. The analysed cultivars continued to show a high level of antioxidant capacity after treatment, which allows the conclusion that they remain a good source of bioactive compounds after transport and short-term storage.

Analysis of Hydrodynamics and Mass Transfer of Gas-Liquid and Liquid-Liquid Taylor Flows in Microchannels

2019 ◽  
pp. 1-49
Author(s):  
Rufat Abiev
Keyword(s):  
Mass Transfer ◽  
Point Of View ◽  
Process Conditions ◽  
Two Phase ◽  
Physical Point ◽  
Micro Channels ◽  
Liquid Systems ◽  
Simplifying Assumptions ◽  
Liquid Flows ◽  
Solid Liquid

Analysis of hydrodynamics and mass transfer Taylor flows in micro channels of both gas-liquid and liquid-liquid systems on the basis of classical theoretical approach with some simplifying assumptions was performed. Results of theoretical analysis for description of hydrodynamic parameters and mass transfer characteristics were confirmed by comparison with the author's own and available in literature experimental data. It was shown that the main parameters of two-phase Taylor flows could be quite precisely described theoretically: mean bubble/droplet velocity, liquid film thickness, real gas holdup (which is always smaller than so-called dynamic holdup), pressure drop. Peculiarities of liquid-liquid flows compared to gas-liquid Taylor flows in capillaries are discussed. Wettability effect on hydrodynamics was examined. Tools of mass transfer intensification of gas-liquid and liquid-liquid Taylor flow in micro channels are analyzed. Three-layer model for heat and mass transfer has been proposed and implemented for the case of solid-liquid mass transfer for gas-liquid Taylor flows; optimal process conditions for this process are found theoretically and discussed from physical point of view.

scholarly journals New insight into the effect of mass transfer on the synthesis of silver and gold nanoparticles

CrystEngComm ◽  
2018 ◽  
Vol 20 (44) ◽  
pp. 7082-7093 ◽  
Author(s):  
Maximilian O. Besenhard ◽  
Razwan Baber ◽  
Alec P. LaGrow ◽  
Luca Mazzei ◽  
Nguyen T. K. Thanh ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Gold Nanoparticles ◽  
Process Conditions ◽  
Silver And Gold Nanoparticles ◽  
Insight Into

Silver and gold nanoparticles were prepared using constant reactant concentrations and temperatures, but different process conditions to alter the mass transfer during synthesis.

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