The Influence of Selected Drying Methods on the Physical Properties of Dried Apples cv. Jonagold Grown in Different Locations in Europe

2017 ◽  
Vol 13 (6) ◽  
Author(s):  
Anna Michalska ◽  
Krzysztof Lech ◽  
Adam Figiel ◽  
Grzegorz P. Łysiak
Keyword(s):  
Physical Properties ◽  
Freeze Drying ◽  
Geographical Origin ◽  
Raw Material ◽  
Convective Drying ◽  
Vacuum Drying ◽  
Drying Methods ◽  
Drying Time ◽  
Microwave Vacuum Drying ◽  
Apple Slices

Abstract The aim of the study was to determine the influence of four different growing locations of apples cv. ‘Jonagold’ in Europe on the drying kinetics and the physical properties of dried apple slices. The drying methods applied in the study (freeze-drying, convective drying, microwave-vacuum drying and combined drying) significantly affected the drying time, which was the shortest in the case of microwave vacuum drying. The geographical origin of the apples affected the chemical and physical properties of the raw material used for drying, and, consequently, the drying time. Water activity of dried samples was connected with the final dry matter, regardless of the geographical origin of the apples. Freeze-drying resulted in the lightest in colour products (L*), whereas microwave-vacuum dried products had the highest levels of yellow pigments (b*). The highest chroma and browning index values were noted for microwave-vacuum dried samples and were strongly influenced by the drying temperature. The mechanical properties of the apple slices were more dependent on the drying method and temperature of the process than on the geographical origin when the temperature exceeded 83 °C.

scholarly journals Evaluation of Innovative Dried Purée from Jerusalem Artichoke—In Vitro Studies of Its Physicochemical and Health-Promoting Properties

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2644
Author(s):  
Jan Oszmiański ◽  
Sabina Lachowicz ◽  
Paulina Nowicka ◽  
Paweł Rubiński ◽  
Tomasz Cebulak
Keyword(s):  
Freeze Drying ◽  
Jerusalem Artichoke ◽  
Polyphenolic Compounds ◽  
Raw Material ◽  
Vacuum Drying ◽  
Drying Methods ◽  
Drying Method ◽  
Activity Inhibition ◽  
Health Promoting

The present study aimed to evaluate the effect of Jerusalem artichoke processing methods and drying methods (freeze drying, sublimation drying, vacuum drying) on the basic physicochemical parameters, profiles and contents of sugars and polyphenolic compounds, and health-promoting properties (antioxidant activity, inhibition of the activities of α-amylase, α-glucosidase, and pancreatic lipase) of the produced purée. A total of 25 polyphenolic compounds belonging to hydroxycinnamic phenolic acids (LC-PDA-MS-QTof) were detected in Jerusalem artichoke purée. Their average content in the raw material was at 820 mg/100 g dm (UPLC-PDA-FL) and was 2.7 times higher than in the cooked material. The chemical composition and the health-promoting value of the purées were affected by the drying method, with the most beneficial values of the evaluated parameters obtained upon freeze drying. Vacuum drying could offer an alternative to freeze drying, as both methods ensured relatively comparable values of the assessed parameters.

scholarly journals Application of sonication and freezing as initial treatments before microwave-vacuum drying of cranberries

2019 ◽  
Vol 2 (22) ◽  
pp. 151-167 ◽  
Author(s):  
Izabela Staniszewska ◽  
Szymon Staszyński ◽  
Magdalena Zielińska
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Physical Properties ◽  
Color Change ◽  
Vacuum Drying ◽  
Drying Time ◽  
Dried Fruits ◽  
Microwave Vacuum Drying ◽  
Drying Kinetic

The aim of study was to determine the influence of sonication and freezing on the kinetic of the microwave-vacuum drying, energy consumption and physical properties of whole cranberries as well as evaluate the applicability of sonication instead of freezing in order to change their physical properties and the drying kinetic of whole cranberries. Microwave-vacuum drying of whole cranberries with/without initial treatments took from 12 ± 1 to 14.5 ± 0.5 minutes. All of treatments did not significantly shorten the drying time of cranberries. However, they increased SMER values even by 31%. Despite of cryogenic freezing, all of treatments significantly increased the values of Dew. Sonication combined with drying allowed to obtain dried berries characterized by the lowest cohesiveness (0.19±0.02), springiness (0.62±0.02) and chewiness (3.4±0.8 N), while cryogenic freezing combined with drying allowed to obtain dried fruits characterized by highest springiness (0.75±0.03) and low chewiness (3.3±0.5 N). The highest lightness (32.2±0.7), redness (32.6±0.8), and yellowness (11.1±0.7) were found for fruits subjected to initial convective freezing before drying. The efficiency of sonication in color change was comparable to cryogenic freezing and much lower than convective freezing. All of initial treatments increased such thermal properties of dried cranberries as thermal conductivity and thermal diffusivity.

scholarly journals Physicochemical Properties of Dried Apple Slices: Impact of Osmo-Dehydration, Sonication, and Drying Methods

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1078
Author(s):  
Joanna Cichowska-Bogusz ◽  
Adam Figiel ◽  
Angel Antonio Carbonell-Barrachina ◽  
Marta Pasławska ◽  
Dorota Witrowa-Rajchert
Keyword(s):  
Physicochemical Properties ◽  
Osmotic Dehydration ◽  
Convective Drying ◽  
Drying Methods ◽  
Drying Method ◽  
Drying Time ◽  
Hygroscopic Properties ◽  
Fruit Samples ◽  
Apple Slices ◽  
Pre Treatment

Apple slices of the Elise variety were previously osmo-dehydrated in erythritol, xylitol, and sucrose for 2 h. In some parts of the experiment, 30 min of ultrasound pre-treatment (US) were applied. Afterwards, fruit samples were dried by convective (CD), microwave-vacuum (VM), and a combined method (CD/VM, mix two of them). The main aim of the research was to characterize an impact of osmotic dehydration, sonication pre-treatment, and drying method on the physicochemical properties of the dried apples. The use of sugar alcohols (xylitol, erythritol) in the production of dried apples did not badly affect the taste of the obtained dried products; it enabled a noticeable cooling/refreshing effect felt in the mouth when consuming a snack, and enabled the production of dried snacks with lower calorific value. Polyol residues in the product were at a level that was safe for consumers. The most popular convective drying was long lasting, whereas the VM drying method allowed for the shortest drying time, amounting to 76 min; moreover, additional application of ultrasounds reduced this time to 36 min. The combined drying method allowed the total duration of the process to be reduced 2–4.5 times. Ultrasound applied during osmotic dehydration did not significantly affect attributes of the descriptive sensory analysis for the obtained dried apples. The best hygroscopic properties, ensuring the storage stability of the dried product, showed dried apples previously osmo-dehydrated in erythritol and sucrose solutions.

scholarly journals Comparative kinetic analysis of convective and vacuum dried Opuntia ficus-indica (L.) Mill. cladodes

2019 ◽  
Vol 65 (No. 1) ◽  
pp. 1-6
Author(s):  
Anirban Dey ◽  
Somya Singhal ◽  
Prasad Rasane ◽  
Sawinder Kaur ◽  
Navneet Kaur ◽  
...  
Keyword(s):  
Convective Drying ◽  
Coefficient Of Determination ◽  
Vacuum Drying ◽  
Drying Methods ◽  
Drying Method ◽  
Statistical Parameters ◽  
Drying Time ◽  
Opuntia Ficus Indica ◽  
Thin Layer Drying ◽  
Drying Behavior

Opuntia ficus-indica (Linnaeus) Miller more usually known as fodder palm or nopal belongs to family Cactaceae. In the present study, the drying behavior of the O. ficus-indica cladodes was observed. The study concentrates on comparatively studying two types of commercial drying methods viz., forced convective drying (tray drying) and vacuum drying to dry nopal cladodes at three different temperatures viz. 40, 50 and 60°C. The equilibrium moisture contents for forced convective drying was achieved at 540–720 min and for that of vacuum drying at 600–840 min. Three mathematical drying models for thin layer drying viz. Page, Lewis and Henderson-Pabis model were evaluated for both convective drying and vacuum drying. Statistical parameters such as the coefficient of determination (R<sup>2</sup>), root mean square error and reduced χ<sup>2</sup> were used to fit the models. Page model was found to be satisfactory for both forced convective and vacuum drying of the nopal cladodes at 40 and 50°C respectively. Among these, two drying methods, forced convective drying method was found to be more suitable than the vacuum drying method for nopal cladodes on the basis of drying time and statistical parameters.

scholarly journals Physicochemical and Quality Properties of Dried Courgette Slices: Impact of Vacuum Impregnation and Drying Methods

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4597
Author(s):  
Magdalena Kręcisz ◽  
Bogdan Stępień ◽  
Marta Pasławska ◽  
Jarosław Popłoński ◽  
Kinga Dulak
Keyword(s):  
Water Activity ◽  
Bioactive Compounds ◽  
Logistic Model ◽  
Freeze Drying ◽  
Convective Drying ◽  
Vacuum Impregnation ◽  
Drying Methods ◽  
Drying Time ◽  
Quality Properties ◽  
Kinetics Of

The aim of this study was to determine the effects that the type of impregnating solution and drying method (freeze drying (FD) and vacuum drying (VD) at 45 °C and convective drying (CD) at 50, 60, and 70 °C) had on the physicochemical and quality properties of courgettes. Courgette slices were vacuum-impregnated (6 kPa) in freshly squeezed onion, kale, and onion and kale (50:50) juices with 3% NaCl solution (N). The application of vacuum impregnation (VI) with impregnating solutions from freshly squeezed onions and kale had a beneficial effect on the bioactive values of courgette. The highest contents of quercetin (41.84 μg/g d.m.) and carotenoids (276.04 μg/g d.m.) were found in courgette impregnated with onion juice after freeze drying. The highest values of lutein and zeaxanthin (216.42 μg/g d.m.) were recorded for courgette impregnated with kale juice and convective dried. By analysing the kinetics of convective drying, the best matching of the logistic model was found. Increasing the drying process temperature from 50 to 70 °C reduced the drying time from 15% to 36%, depending on the type of impregnating solution used. Water activity <0.6 was recorded for courgette dried by freezing, vacuum, and convection at 60 and 70 °C. Conclusions: The vacuum impregnation process and the impregnation solutions from freshly squeezed vegetables can be used to develop new snacks with high levels of bioactive compounds. The FD method is the most appropriate considering both the bioactive compounds content and the obtained colour and water activity.

scholarly journals Freeze-drying techniques for preserving aphids (Homoptera, Aphidodea)

1994 ◽  
Vol 5 (2) ◽  
pp. 105-113 ◽  
Author(s):  
Anders Albrecht
Keyword(s):  
Freeze Drying ◽  
Body Shape ◽  
Vacuum Drying ◽  
Drying Methods ◽  
Drying Time ◽  
Freeze Dried ◽  
Drying Techniques ◽  
Wax Coating ◽  
And Storage

Techniques for collection, preparation and storage of freeze-dried aphid samples, including galls, are described. Freeze-drying can be done with the aid of a home freezer, a drying agent, and suitable containers alone, but drying time can be reduced considerably with cheap and simple vacuum drying equipment. Freeze-drying methods have several advantages compared with traditional mounting techniques. Body shape, colours, wax coating and microsculpture are excellently preserved. The labour required per sample, for preparation as well as for identification, is reduced to a minimum, and complete colony samples can be stored as entities. Aspects of practical handling and study of freeze-dried aphid samples are discussed.

scholarly journals Ambient temperature drying of therapeutic protein solution with use of microwave

2018 ◽  
Author(s):  
Takaharu Tsuruta ◽  
Takuma Ogawa ◽  
Ryosuke Abe ◽  
Hirofumi Tanigawa
Keyword(s):  
Ambient Temperature ◽  
Protein Conformation ◽  
Freeze Drying ◽  
Protein Structures ◽  
Egg White ◽  
Therapeutic Protein ◽  
Vacuum Drying ◽  
Protein Solution ◽  
Drying Time ◽  
Microwave Vacuum Drying

High quality drying of therapeutic protein-solution is important in medical and pharmaceutical processing.  Freeze-drying is mostly used, but it takes a long drying-time and causes damages of protein structures.  In order to improve the drying quality, we propose a microwave vacuum drying performed at ambient temperatures under low-pressure conditions.  We are focusing on the Parma-Zyme method for the evaporative drying of protein solutions such as egg white or lysozyme with vitrification. Circular dichroism (CD) spectroscopy is used to detect protein conformation changes due to the drying, and it is found that the ambient temperature drying can preserve the protein conformation. Keywords: Microwave vacuum drying; Freeze-drying; Therapeutic protein; Egg white; Lysozyme 

Kinetics of Microwave Vacuum Drying of “Cat Chu” Mango in Mekong Delta - Vietnam

2015 ◽  
Vol 656-657 ◽  
pp. 573-579 ◽  
Author(s):  
Cuong Nguyen Van ◽  
Hau Tran Tan
Keyword(s):  
Mekong Delta ◽  
Convective Drying ◽  
Vacuum Drying ◽  
Second Phase ◽  
High Quality ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Microwave Vacuum Drying ◽  
Hot Air

Microwave vacuum drying is one of innovative drying techniques that is today used in drying of foods, medical products and other high quality products. In this drying technology, heat is generated by directly transforming the electromagnetic energy into kinetic molecular energy of water, thus the heat is produced deep within the material to be dried under vacuum environment. This paper presents the results of research on microwave vacuum drying of “Cat Chu” mango in Mekong Delta – Vietnam. “Cat Chu” mango, with moisture content of (80 ± 1) % (wet basis - wb), was sliced into 5 cm thickness, and was dried in mWaveVac0150-lc dryer (Püschner - Germany). The drying vacuum was from 60 to 120 mbar. Three levels of microwave power were established: the first phase from 600 to 800 W, the second phase from 300 to 500 W, the last one from 150 to 250 W. The control sample was dried by convective drying method at 60 °C; and vacuum drying at 70 mbar, 60 °C. The results of this research showed that high quality product in terms of color, surface shrinkage and structure was obtained by microwave vacuum drying. The drying time was about 45 min, 450 min and 870 min with microwave vacuum drying, vacuum drying and convective hot-air drying, respectively. In addition, Fick’s equation and Crank’s solution were applied to analyze and calculate the accessibility and diffusion coefficient of microwave vacuum drying process. Starting accessibility of process was significantly increased; the diffusivity obtained was within a range from 6.44*10-10 m2/s to 16.16*10-10 m2/s. The results also indicated that there was a higher exchange in surface and a greater internal diffusion of experimental microwave vacuum drying samples compared to the control vacuum and hot-air drying samples.

scholarly journals The Effect of Hybrid Drying (Convective-Microwave-Ultrasound) on the Bioactive Properties of Osmo-Treated Sour Cherries

2018 ◽  
Vol 26 (1) ◽  
pp. 23-36 ◽  
Author(s):  
Karolina Celejewska ◽  
Monika Mieszczakowska-Frąc ◽  
Dorota Konopacka
Keyword(s):  
Sour Cherry ◽  
Raw Material ◽  
Convective Drying ◽  
Water Evaporation ◽  
Drying Methods ◽  
Drying Time ◽  
Hybrid Techniques ◽  
Osmotic Treatment ◽  
Fruit Preservation

Abstract The aim of the study was to assess the usefulness of hybrid drying methods (convective-microwave and convective-microwave-ultrasound) for sour cherry fruit preservation compared to convective drying. As the raw material, three sour cherry cultivars varying in quality characteristics (‘Łutówka’, ‘Debreceni Bötermo’, ‘Nefris’) were used. Before drying, fruits were subjected to osmotic treatment. Three different drying methods were examined: 1) convective (C), 2) hybrid with microwaves (C-MV) and 3) hybrid with microwaves and ultrasound (C-MV-US). As the quality indicators of the investigated processes, the changes in chemical composition, including alterations in the main groups of bioactive components, as well as in the antioxidant potential were monitored at each production stage. It was found that, when compared to convective drying, the use of the hybrid techniques allowed the drying time to be reduced from 9 to just 3 hours. Furthermore, employing hybrid drying eliminated the problems associated with the dehydration barrier observed during convective drying of the cultivar ‘Debreceni Bötermo’. Regrettably, although the ultrasound used as the additional source of energy in the hybrid method slightly improved water evaporation, in general no significant effect on the retention of phenolic compounds was found. Irrespectively of the drying method, the effect of the cultivar proved to be crucial to the quality of the final product. Under the same processing conditions, ‘Nefris’ turned out to be the most promising cultivar for producing ready-to-eat fruit snacks of high nutritional value.

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