scholarly journals Ultrasound enhancement of osmotic dehydration and drying – Process kinetics and quality aspects

2018 ◽  
Author(s):  
Grzegorz Musielak
Keyword(s):  
Osmotic Dehydration ◽  
Convective Drying ◽  
Drying Process ◽  
Process Kinetics ◽  
Vibration Effect ◽  
Quality Aspects ◽  
Wide Range ◽  
Osmotic Agents ◽  
Ultrasound Enhancement

The aim of presented studies is to investigate of influence of ultrasonic assistance on both osmotic dehydration and convective drying. A wide range of different materials, as well as several osmotic agents were tested. The obtained results show that the use of ultrasound always accelerates the investigated processes. The application of ultrasound may reduce the energy consumption of drying. Qualitative studies of dried materials do not give a definite answer about the effect of ultrasound on the quality of the products. Mathematical modelling of the ultrasound assisted drying indicates that so named “vibration effect” plays the biggest role in convective drying acceleration. Keywords: osmotic dehydration; convective drying;  ultrasound; process kinetics.

scholarly journals Ultrasound-assisted osmotic dehydration and convective drying of apples: Process kinetics and quality issues

2016 ◽  
Vol 37 (3) ◽  
pp. 383-391 ◽  
Author(s):  
Dominik Mierzwa ◽  
Stefan J. Kowalski
Keyword(s):  
Osmotic Dehydration ◽  
Colour Change ◽  
Apple Fruit ◽  
Point Of View ◽  
Convective Drying ◽  
Drying Process ◽  
Drying Time ◽  
Ultrasound Enhancement ◽  
Kinetics Of

Abstract The aim of the present theme issue was to study the influence of ultrasound enhancement on the kinetics of osmotic dehydration and the effect of convective drying from the point of view of drying time and quality of dried products. Apple fruit was used as the experimental material. The kinetics of osmotic dehydration with (UAOD) and without (OD) ultrasound enhancement were examined for 40% fructose and sorbitol solutions. The effective dehydration time of osmotic process was determined. Preliminary dehydrated samples with OD and UAOD were next dried convectively with (CVUS) and without (CV) ultrasound assistance. The influence of OD and UAOD on the kinetics of CV and CVUS drying was analysed. The parameters of water activity and colour change were measured for the assessment of product quality after drying process.

scholarly journals Influence of preliminary osmotic dehydration on drying kinetics and final quality of carrot (Daucus carota L.)

2011 ◽  
Vol 32 (3) ◽  
pp. 185-194 ◽  
Author(s):  
Stefan Kowalski ◽  
Dominik Mierzwa
Keyword(s):  
Daucus Carota ◽  
Osmotic Dehydration ◽  
Drying Kinetics ◽  
Convective Drying ◽  
Drying Time ◽  
Solid Gain ◽  
Visual Appearance ◽  
Daucus Carota L ◽  
Colorimetric Measurements

Influence of preliminary osmotic dehydration on drying kinetics and final quality of carrot (Daucus carotaL.)This paper concerns convective drying of carrot preliminary dehydrated in aqueous solutions of three types of osmotic agents (sucrose, fructose, glucose). Three solution concentrations (20, 40 and 60%) were examined to work out efficient conditions of osmotic dewatering. The parameters such as water loss (WL), solid gain (SG) and osmotic drying rate (ODR) indicating the real efficiency of osmotic dehydrations (OD) were determined. The samples dehydrated with osmotic solutions underwent further convective drying to analyze influence of dehydration process on drying kinetics and final products quality. The quality of products was assessed on the basis of visual appearance of the samples and colorimetric measurements. It was found that osmotic pretreatment improves significantly the final product quality as the samples were less deformed and their colour was better preserved compared to samples, which had not been preliminarily dehydrated. Preliminary dehydration, however, did not influence significantly the overall drying time of the samples.

scholarly journals Influence of Dehydration in the Physical-Chemical Quality of Commercial Sunflower Almonds

2019 ◽  
Vol 7 (2) ◽  
pp. 82
Author(s):  
Sâmela Leal Barros ◽  
Newton Carlos Santos ◽  
Amanda Priscila da Silva Nascimento ◽  
Mylena Olga Pessoa Melo ◽  
Victor Herbert de Alcântara Ribeiro ◽  
...  
Keyword(s):  
Water Activity ◽  
Convective Drying ◽  
Drying Process ◽  
Physical Damage ◽  
Physical Chemical ◽  
Significant Difference ◽  
Before And After ◽  
Different Temperatures ◽  
Useful Life

Sunflower almonds are widely marketed and have numerous technological applications. Through the drying process occurs the reduction of the water content of the product, a factor that contributes to increase its useful life. However, nutritional losses and physical damage can also occur. In this context, the objective of this study was to evaluate the effect of different temperatures applied in the drying process on the physical-chemical characteristics of commercial sunflower almonds. Convective drying was performed using temperatures of 40, 50, 60 and 80 °C. Afterwards, the samples before and after the drying process were analyzed with respect to the following parameters: moisture, water activity, ash, lipids, proteins, carbohydrates and energetic value to observe the influence of different drying temperatures on these attributes. It was verified that the increase of the temperature of the drying air causes an increase in the ash content, total solids, lipids, carbohydrates and energetic value. However, the reduction of moisture content, water activity and proteins was observed. There was no significant difference between the samples in relation to pH.

scholarly journals Exergetic, Energetic, and Quality Performance Evaluation of Paddy Drying in a Novel Industrial Multi-Field Synergistic Dryer

Energies ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 4588 ◽  
Author(s):  
Li ◽  
Li ◽  
Li ◽  
Zeng ◽  
Ou ◽  
...  
Keyword(s):  
Heat Recovery ◽  
Radiant Energy ◽  
Generation Rate ◽  
Drying Process ◽  
Quality Performance ◽  
Improvement Potential ◽  
Quality Aspects ◽  
Energy And Exergy ◽  
Quality Aspect

The present work proposes a novel industrial multi-field synergistic dryer with a drying capacity of 3.45 t/h. The energy, exergy, and quality aspects of the drying process were studied. An energy–exergy methodology was employed to estimate the energetic and exergetic performance, heat loss characteristics and heat recovery behavior of the dryer. Additionally, the quality of the dried paddy seeds was evaluated by its crackle ratio, generation potential, and generation rate. The results showed that the overall energy and exergy efficiency ranged from 13.26% to 56.63% and 39.03% to 60.23%, respectively. The improvement potential rates of the whole system varied from the lowest 8.49 kW to the highest 15.83 kW and respectively accounted for 15.81%–29.48% of the total exergy input, indicating that the performance of the dryer is acceptable. The total recovered radiant energy and radiant exergy recover rate were respectively ascertained to be 237.64 MJ and 0.26 kW. As for the quality aspect, the generation potential and generation rate of the dried paddy seeds respectively ranged from 75% to 90% and 69% to 88% while the crackle ratio of the paddy seeds was 1%, which indicated that the quality performance of the dried seed is of economic viability.

Drying Behaviour and Energy Requirement for Dehydration of White Onion Slices

2007 ◽  
Vol 3 (5) ◽  
Author(s):  
Vithhal Revaskar ◽  
Gyanendra Prakash Sharma ◽  
Radha Charan Verma ◽  
S.K. Jain ◽  
V.K. Chahar
Keyword(s):  
Air Temperature ◽  
Osmotic Dehydration ◽  
Energy Requirement ◽  
Specific Energy Consumption ◽  
Moisture Diffusivity ◽  
Convective Drying ◽  
Nacl Solution ◽  
Solid Gain ◽  
Drying Behaviour

White onions were dried using an osmo-convective drying technique. Osmotic dehydration was done by dipping the onion slices in 10, 15 and 20 brix NaCl solution at ambient temperature for one hour. The increase in the concentration of NaCl increased the water loss, solid gain and weight reduction in onion slices. The drying times of pre-osmosed onions slices at drying air temperature of 50, 60 and 70°C were 6.75, 6.00 and 5.25 h respectively. The moisture diffusivity increased with increase in air temperature and ranged between 0.83 and 0.91x10-10 m2/s. Quality of dried product in respect to flavour strength and color was superior. A lowest specific energy consumption of about 1.98 kWh/kg was found in the air drying of onions pre-treated with 20 brix NaCl solution and at air temperature of 70°C.

scholarly journals Structure of coarse woody debris in Lange-Leitn Natural Forest Reserve, Austria

2008 ◽  
Vol 54 (No. 4) ◽  
pp. 161-169 ◽  
Author(s):  
M. Rahman M ◽  
G. Frank ◽  
H. Ruprecht ◽  
H. Vacik
Keyword(s):  
Coarse Woody Debris ◽  
Structural Characteristics ◽  
Woody Debris ◽  
Natural Forest ◽  
Nature Management ◽  
Forest Reserve ◽  
Quality Aspects ◽  
Wide Range ◽  
Range Of Variation

The amount, variability and quality of coarse woody debris (CWD) in an oak-dominated natural forest reserve in Austria were studied in 2006. The average volume of CWD (snags and logs) was 107.3 m<sup>3</sup>/ha, which accounted for 39% of the total living volume. Among the CWD, on average, 23.4 m<sup>3</sup>/ha (22%) were snags and 83.9 m<sup>3</sup>/ha (78%) were logs. According to quality aspects the CWD displayed a wide range of variation in tree species, tree size, stage of decay, and structural characteristics, creating a high diversity of CWD habitats for microorganisms. Among the three forest associations, the highest amount of CWD was found in the mesic <I>Galio sylvatici-Carpinetum</I> association. The results of this study are discussed as reference values for a close-to-nature management of oak-dominated broadleaved submontane forests emphasizing conservation management.

scholarly journals Quality Aspects of Fruit and Vegetables Dried Convectively with Osmotic Pretreatment

2013 ◽  
Vol 34 (1) ◽  
pp. 51-62 ◽  
Author(s):  
Stefan J. Kowalski ◽  
Joanna M. Łechtańska ◽  
Justyna Szadzińska
Keyword(s):  
Water Loss ◽  
Fruits And Vegetables ◽  
Osmotic Dehydration ◽  
Convective Drying ◽  
Quality Analysis ◽  
Banana Fruit ◽  
Time Intervals ◽  
Dried Fruits ◽  
Quality Aspects ◽  
Drying Curves

Abstract This article presents a quality analysis of convectively dried fruits and vegetables with preliminary osmotic dehydration. Tests were carried out on banana fruit and red beetroot samples. Hypertonic solutions of fructose for the banana and those of sucrose for the red beetroot were used, each one at three different concentrations. After osmotic dewatering treatment conducted at different time intervals and after osmotic dehydration the samples were dried convectively until an equilibrium with the surroundings was attained. Osmotic dehydration and convective drying curves were determined. The values of Solids Gain (SG), Water Loss (WL) and Weight Reduction (WR) were measured and changes in the samples’ colour and shape after convective drying with and without osmotic pretreatment were assessed.

scholarly journals Kinetics of Convective Drying and Quality of Pears Cultivars Conference, Lucas, Abate

2012 ◽  
Vol 69 (2) ◽  
Author(s):  
Ionuț VELEȘCU ◽  
Vasile DOBRE ◽  
Ioan ŢENU
Keyword(s):  
Technological Process ◽  
Air Temperature ◽  
Oxidation Process ◽  
Convective Drying ◽  
Maximum Speed ◽  
Drying Process ◽  
Temperature And Humidity ◽  
Kinetics Of

Abstract. The objective of this study is the kinetics process of drying of the pears cv. Conference, cv. Abate and cv. Lucas with a laboratory dryer, in order to identify at which level of humidity the maximum speed of evaporation is achieved and at which level of temperature and humidity pears slices begin to change (colour and shape) and to determine which one of the three tested varieties offers the best properties for drying, which will ensure that the final product is technologically and organoleptically the most acceptable. Drying parameters were the same for all three varieties: 2 hours at air temperature 90oC, 2 hours at air temperature 80oC, 2 hours at air temperature 70 C and 2 hours at air temperature 60o C.  The results showed that the sample of the cv. Conference has undergone the least oxidation process, rounded edges and shriveled slices, and samples of the cv Lucas showed the worst results. Following the drying process of all three varieties, it can be concluded that the cultivars Abate and Conference achieved the lower evaporation speed, unlike the cv. Lucas. The cultivars Conference and Abate have attained consistent drying and in this way the technological process was finished with a smaller temperature, resulting in a better quality of the final product. o

scholarly journals Osmotic dehydration and convective drying of kiwifruit (Actinidia deliciosa) – The influence of ultrasound on process kinetics and product quality

2021 ◽  
Vol 71 ◽  
pp. 105377
Author(s):  
Joanna Kroehnke ◽  
Justyna Szadzińska ◽  
Elżbieta Radziejewska-Kubzdela ◽  
Roża Biegańska-Marecik ◽  
Grzegorz Musielak ◽  
...  
Keyword(s):  
Product Quality ◽  
Osmotic Dehydration ◽  
Actinidia Deliciosa ◽  
Convective Drying ◽  
Process Kinetics

scholarly journals FEATURES OF THE TECHNOLOGICAL LINE OF THERMAL PROCESSING OF SMALL-SEEDED CROPS

2018 ◽  
Vol 18 (2) ◽  
Author(s):  
L. K OVSIANNYKOVA
Keyword(s):  
Heat Treatment ◽  
Seed Quality ◽  
Drying Process ◽  
Post Harvest ◽  
Technological Line ◽  
Wide Range ◽  
Post Harvesting ◽  
Processing And Storage ◽  
Seed Crops

Despite successes, many problems are encountered with small-seed crops (sorghum, turnip, mustard, linen, etc.), for many of them there are not enough recommendations of regulations and other normative and technological documentation. The article is devoted to ways of improving the drying process of freshly harvested grain. It is known that during post-harvest processing, small-seeded crops undergo a certain thermal effect at certain stages of it. First of all, this regards, drying and cooling processes. Meanwhile, heat treatment is a complex technological process in which numerous physical-mechanical and biochemical changes, sometimes irreversible, occur in oil seed. In addition, heat treatment is the most energy-efficient. Timely and proper drying of grain not only increases its stability during storage, but also improves food and seed quality of grain. As a result of drying, post-harvest maturing is accelerated, humidity is leveled and technological properties change. Drying has a positive effect on the yield and quality of grain and products of its processing. To our regret, there are almost no studies of drying process of small-seeded crops grown in Ukraine. Meanwhile, drying is an important link in the post-harvesting process of corn. The paper gives recommendations on drying technology of crops (sorghum) and oilseeds (turnip, mustard, flax) of smallseeded food crops in grain-harvesting enterprises. The basic scheme of technological line of heat treatment of small-seeded crops and recommendations for reducing energy intensity and increasing the efficiency of heat treatment and improving their quality are developed. The main purpose of this article is to familiarize a wide range of specialists in the field of post-harvest processing and storage of grain with drying regimes and the scheme of technological drying line of small-seeded crops.

Sign in / Sign up

Export Citation Format

Share Document