scholarly journals Effect of Convective Drying Method of Chokeberry (Aronia melanocarpa L.) on Drying Kinetics, Bioactive Components and Sensory Characteristics of Bread with Chokeberry Powder

Author(s):  
Marko Petković ◽  
Igor Đurović ◽  
Nemanja Miletić ◽  
Jovana Radovanović

The effects of three dehydration temperatures at 50, 60 and 70 °C of convective drying method on fresh fruits of black chokeberries (Aronia melanocarpa L.) were evaluated. The drying temperatures were found to have significantly different effects on the characteristics of dried fruits and powders, made by the dried fruits. The maximum drying rate at a temperature of 50 °C was 59 g/h, at 60 °C 102 g/h, and at 70 °C 115 g/h, and thus the drying time was 37 hours, 27 hours and 23 hours respectively. The drying temperature at 50 °C caused the least damage to the cell structure of the fresh chokeberries, bioactive components (anthocyanins, flavonoids, phenols) and total antioxidativity. The dehydrated chokeberries at the temperature of 50 °C had the highest ratio of total anthocyanins (376.89 ± 5.73 mg cyn-3-glu / 100 g dm), total flavonoids (1037.19 ± 3.83 mg CE / 100 g dm), phenols (1918.79 ± 3.26 mg GAE / 100 g dm) and antioxidant activity (37.11 ± 0.28 mg TE / 100 g dm). The drying process at a temperature of 50 °C required longer drying period, higher energy need and produced the chokeberry powder, which gave the bread with the best sensory characteristics, compared to a drying process at a temperature of 60 °C and 70 °C.

2020 ◽  
pp. 223-223
Author(s):  
Mihailo Milanovic ◽  
Mirko Komatina ◽  
Ivan Zlatanovic ◽  
Nebojsa Manic ◽  
Dragi Antonijevic

The efficient utilization of waste from food industry is possible after thermal treatment of the material. This treatment should be economically feasible and compromise the energy efficient drying process. The main goal of this investigation is to determine drying characteristics of nectarine pomace as a waste from food industry. The measurements were performed in an experimental dryer by combined conductive-convective drying method with disk-shaped samples of 5, 7 and 10mm thickness and 100 mm in diameter at the air temperatures of 30, 40, 50, 60 and 70oC, hot plate temperatures of 50, 60 an 70oC and air velocity of 1.5 m/s. The drying curves were compared to a few semi-theoretical mathematical models. The Logarithmic model showed the best correspondence. On the basis of experiments, it is determined that the drying process takes place in a falling rate period and it is accepted that the main mechanism of moisture removal is diffusion. The effective coefficient of diffusion was determined using experimental results by calculating the slope of the drying curves. Drying time and equilibrium moisture are determined for each experiment. Analysis of drying curves showed that the conductive-enhanced drying method reduces drying times and increases the diffusivity coefficient. The character of drying rate curves for conductive-enhanced drying was analyzed and compared with pure convective drying of nectarine pomace.


Author(s):  
Narotam Soni

Fresh custard apple pulp was dehydrated using convective drying method to study the effect of drying temperatures on effective diffusivity of custard apple pulp. Dehydration characteristics of custard apple pulp for the convective drying experiment were studied. Moisture diffusivity (Deff) at 50, 55, 60 and 65° C temperatures was ranged from 3.20 x10-9 m2/s to 4.80 x 10-9 m2/s and activation energy was found 29.436 kJ/mol at air velocity of 2 m/s. The average drying time was decreased 16.67, 10.00 and 22.22 for per 5 °C temperature increase. It was also found that greater drying effect of 22 per cent reduction in drying time was observed for 60 to 65 °C temperature increase. During the drying experiment and data were recorded, it was found that highest drying rate during the drying process was about thrice of the average drying time. It can be deduced from the study that drying process was fast at higher temperature and as the drying temperature increased the effective moisture diffusivity was also increased.


Author(s):  
Е.Е. УЛЬЯНЧЕНКО

При производстве табачного сырья важную роль играет сокращение продолжительности сушки табачных листьев. Одним из способов интенсификации сушки свежеубранных табачных листьев является прием прорезания средней жилки (ПСЖ) листьев вдоль волокон. По результатам исследований 2019–2020 гг. была создана база данных табачного сырья, полученного при естественном способе сушки с применением приема ПСЖ, которая может служить информационным материалом для производителей табака. Проведена оптимизация процесса сушки табачного листа ПСЖ по показателям качества табачного сырья для расширенного диапазона сортотипов табака. Объектом исследований были сорта отечественной селекции, включенные в Государственный реестр селекционных достижений, допущенные к использованию: Самсун 85, Вирджиния 202, Юбилейный новый 142, Трапезонд 92, Трапезонд 204, Дюбек 33, Американ 287 и Крупнолистный Ильский (находится в стадии государственных испытаний). Критерием оценки эффективности применения приема ПСЖ на исследованных сортах табака являлся совокупный сравнительный анализ следующих показателей контрольных (без ПСЖ листа) и опытных образцов: уровень интенсификации сушки, показатели товарного качества, технологических свойств и химического состава полученного сырья. Установлено, что ПСЖ позволяет интенсифицировать процесс сушки в 1,3–2,46 раза в зависимости от сорта табака и положительно влияет на технологические свойства сырья, у большинства сортов увеличивается выход волокна и сохраняются объемно-упругие свойства. Динамика сушки оказывает влияние на изменение химического состава сырья. В процессе сушки за счет гидролизации солей никотина и его освобождения путем окисления кислородом воздуха уровень никотина в ряде образцов снижается в пределах 10–30%. Чем выше содержание никотина, тем выше крепость табака, грубее его вкус. Изменения углеводно-белкового соотношения в сторону повышения углеводов улучшают вкусовые характеристики сырья. По каждому исследованному сорту не удалось выявить закономерной зависимости его структуры и характера процесса сушки при ПСЖ с преобразованиями химического состава сырья. На основе анализа технологических и качественных показателей табачного сырья, представленных в разработанной базе данных по интенсификации сушки различных сортов табака с применением приема ПСЖ табачных листьев, можно планировать выбор оптимального способа сушки для каждого сорта табака, позволяющего повысить эффективность использования сырья и улучшить его качественные характеристики. In the production of tobacco raw materials, reducing the drying time of tobacco leaves plays an important role. One of the ways to intensify the drying of freshly harvested tobacco leaves is the method of cutting the middle vein (CMV) of the leaves along the fibers. Based on the results of research in 2019–2020, a database of tobacco raw materials obtained by a natural drying method using CMV reception was created, which can serve as information material for tobacco producers. The optimization of the process of drying the CMV tobacco leaf according to the quality indicators of tobacco raw materials for an expanded range of tobacco variety types was carried out. The object of research was the varieties of domestic selection included in the State Register of Breeding Achievements, approved for use: Samsun 85, Virginia 202, Yubileyny novy 142, Trapezond 92, Trapezond 204, Dubek 33, American 287 and Krupnolistnyy Ilskiy (under state testing). The criterion for evaluating the effectiveness of the use of CMV intake on the studied tobacco varieties was a cumulative comparative analysis of the following indicators of control (without CMV sheet) and experimental samples: the level of drying intensification, indicators of commercial quality, technological properties and chemical composition of the obtained raw materials. It is established that CMV allows to intensify the drying process by 1,3–2,46 times, depending on the tobacco variety and has a positive effect on the technological properties of raw materials, most varieties increase the yield of fiber and retain volume-elastic properties. The dynamics of drying affects the change in the chemical composition of raw materials. During the drying process, due to the hydrolysis of nicotine salts and its release by oxidation with air oxygen, the nicotine level in a number of samples decreases within 10–30%. The higher the nicotine content, the higher the strength of tobacco, it is coarser in taste. Changes in the carbohydrate-protein ratio in the direction of increasing carbohydrates improve the taste characteristics of raw materials. For each studied variety, it was not possible to identify a regular dependence of its structure and the nature of the drying process at CMV with transformations of the chemical composition of raw materials. Based on the analysis of technological and qualitative indicators of tobacco raw materials presented in the developed database on the intensification of drying of various varieties of tobacco using the use of CMV of tobacco leaves, it is possible to plan the choice of the optimal drying method for each variety of tobacco, which allows to increase the efficiency of using raw materials and improve its quality characteristics.


Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1078
Author(s):  
Joanna Cichowska-Bogusz ◽  
Adam Figiel ◽  
Angel Antonio Carbonell-Barrachina ◽  
Marta Pasławska ◽  
Dorota Witrowa-Rajchert

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.


2019 ◽  
Vol 42 ◽  
pp. e43451 ◽  
Author(s):  
Gutierres Nelson Silva ◽  
José Antônio Saraiva Grossi ◽  
Marcela Silva Carvalho ◽  
Kacilda Naomi Kuki ◽  
Samuel de Melo Goulart ◽  
...  

Macauba fruits are oil-rich drupes with high moisture content at harvest. This feature can affect the chemical properties of the oil and increase the costs of biodiesel production. Therefore, it is necessary to adopt postharvest strategies to ensure oil quality. The aim of this work was to evaluate the effect of drying macauba fruit on the quality of the pulp oil. Husked and dehusked fruits were dried at 60°C and then stored. At 0, 15, 45, 100, and 180 days after storage, fruit samples were retrieved, and the oil from the pulp was evaluated for physicochemical parameters. The removal of the husk from the fruits considerably reduced the drying time compared to that of the husked fruits. Drying prevented deterioration of the fruit even after 180 days of storage, regardless of the presence of the husk. The drying process allowed for efficient storage of the macauba fruit while maintaining low levels of oil acidity. Furthermore, the oxidative stability of the pulp oil from the dehusked dried fruits lasted longer than that from the husked dried fruits. Therefore, drying is a viable alternative for the postharvest of macauba fruits to maintain the quality of the oil for biodiesel production.


2013 ◽  
Vol 5 (6) ◽  
pp. 609-614
Author(s):  
Osvaldas Šlepikas ◽  
Audrius Čereška

The paper deals with biofuel drying process efficiency opportunities.Research was carried out with a special stand and performingexperiments. Experimental rig consists of an ultrasonic generator,ultrasonic transducer, a drying chamber and the humidity,temperature gauge. Tests were used for wood pellets. During theexperiment, they were irrigated with water, dried with hot air andadditionally exposed to different frequency ultrasonic vibrations.The tests results have showed that the convective drying processis combined with the ultrasonic vibrations, the drying time isreduced, which means a positive impact on the ultrasonic process.Studies have confirmed that the effectiveness of convectivedrying method combined with operating ultrasonic vibrationsincreases. Santrauka Straipsnyje nagrinėjamos biokuro džiovinimo proceso efektyvumo didinimo galimybės. Tyrimams atlikti sukurtas specialus stendas ir sudaryta eksperimento atlikimo metodika. Eksperimentinį stendą sudaro ultragarsinis generatorius, ultragarsinis keitiklis, džiovinimo kamera ir drėgmės, temperatūros matuokliai. Buvo tiriamos medžio granulės. Eksperimento metu jos buvo drėkinamos vandeniu, džiovinamos karštu oru ir papildomai veikiamos skirtingo dažnio ultragarsiniais virpesiais. Atlikus bandymus, rezultatai parodė, kad, veikiant konvekcinio džiovinimo procesą ultragarsiniais virpesiais, džiovinimo laikas sutrumpėja. Tai reiškia teigiamą ultragarso poveikį procesui. Tyrimais patvirtintas konvekcinio džiovinimo metodo efektyvumo, papildomai veikiant ultragarsiniais virpesiais, padidėjimas.


Author(s):  
Fabiano An. Fernandes ◽  
Sueli Rodrigues

Abstract Genipap (Genipa americana L.) is an exotic tropical fruit that can be used in production of sweets, liqueurs, and several other foodstuffs. In this work the effect of ultrasonic pre-treatment prior to air-drying on dehydration of genipap was investigated. The study allowed estimating the water diffusivity in the air-drying process for genipaps submitted to ultrasound. Results showed that the water diffusivity increased after application of ultrasound and that the overall drying time was reduced by 28.2%. During the ultrasonic treatment, genipaps lost sugar showing that the ultrasonic pre-treatment can be a valuable process to produce dried fruits with lower sugar content.


2019 ◽  
Vol 65 (No. 1) ◽  
pp. 1-6
Author(s):  
Anirban Dey ◽  
Somya Singhal ◽  
Prasad Rasane ◽  
Sawinder Kaur ◽  
Navneet Kaur ◽  
...  

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.


Author(s):  
I. A. Shorstkii ◽  
D. A. Khudyakov

The transition to an efficient economy and efficient production requires building the foundations for the development of energy efficient technologies and the drying of biomaterials to convert them into useful products. The purpose of this work is to analyze the effectiveness of pretreatment with a pulsed electric field (PEF) in the process of convective drying of biomaterials. The PEF was processed with electric field strength of 2, 4 and 6 kV/cm, the number of pulses 500, with a pulse duration of 50 ?s. Based on the electrical conductivity data of the biomaterial, the index of the disintegration 56% was determined before and after the PEF treatment, which confirms the existence of an electroporation mechanism of the material structure. The drying process is presented with a description of various mathematical models. PEF pre-treatment with the parameters of electric field strength 4 and 6 kV / cm and the number of impulses 500 allowed to reduce the drying time by 13.8% for the value E = 0.02. Total time spent on the drying process reduced by 20-25 minutes. It should be noted that the total energy spent on PEF pre-treatment (<150 W / kg) compared with the energy spent on the drying process is incommensurably small. Statistical analysis of the considered mathematical models showed good convergence of most models with experimental data. The considered technology of pretreatment of PEF can ensure the effective processing of biomaterials in the required amount to obtain high-quality and safe products. Obtained data of the kinetics process can be used to the mathematical model of the drying process design with the use of preliminary treatment processing.


The convective drying process is used to dry onion-slices. The drying experiments are conducted at a drying temperature of 50oC, 60oC, 70oC, and at an air velocity of 1.99, 3.54, 5.66, and 7.52 m/s. The objective is to study the influence of tray position on drying of dark red onion. The work diverges in analyzing drying constants at air velocity beyond 2 m/s. The moisture ratio for the middle tray is greater compared to the top and bottom tray. A smaller moisture ratio is observed for 60°C compared to 50 and 70°C. Moisture removal per unit mass flow rate ratio is lowest observed for bottom tray with 60°C. The ratio of moisture content and mass flow rate for 60 and 70 °C, displays a downward trend with drying time. The randomness in the drying rate at 60 °C and 70 °C is comparatively lesser than 50 °C.


Sign in / Sign up

Export Citation Format

Share Document