scholarly journals Wild Strawberry Fragaria vesca L.: Kinetics of Fruit Drying and Quality Characteristics of the Dried Fruits

Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1265
Author(s):  
Andrzej Krzykowski ◽  
Dariusz Dziki ◽  
Stanisław Rudy ◽  
Urszula Gawlik-Dziki ◽  
Emilia Janiszewska-Turak ◽  
...  

The aim of this study was to determine the effect of the temperature of convection and freeze–drying of wild strawberry Fragaria vesca L. fruits on the drying kinetics and on selected quality features of the dried fruits. The process of convection drying was carried out at the temperatures of 25 °C, 40 °C, and 60 °C, whereas freeze–drying was carried out at the temperatures of 20 °C, 40 °C, and 60 °C of the heating shelves and at the pressure of 63 Pa in the lyophilizer chamber. The drying kinetics were best described by the Midilli model for both drying methods. An increase of the drying temperature to 60 °C, for both convection drying and freeze–drying, resulted in a decrease of the total content of phenolic compounds and of the antioxidant activity of the dried fruits. An increase in the temperature of convection drying reduced the lightness of the dried fruits. However, during freeze–drying, these features changed little despite the increase in the drying temperature. The dried fruits with the highest brightness were obtained at a freeze–drying temperature of 60 °C. The method of freeze–drying is proposed as the best because of the resulting color, L-ascorbic acid retention, and antioxidant properties of the dried fruits.

2018 ◽  
Vol 192 ◽  
pp. 03023
Author(s):  
Natthacha Chaloeichitratham ◽  
Pornkanya Mawilai ◽  
Thadchapong Pongsuttiyakorn ◽  
Pimpen Pornchalermpong

In this study, the effects of two drying methods: hot-air and freeze drying for Thai green curry paste in a terms of drying time and qualities have been investigated. The hot-air drying was carried out in tray dryer at temperature of 50, 60 and 70 °C. The freeze drying was carried out in freeze dryer at freezing temperature of -20°C, primary drying temperature of -10°C and secondary drying temperature of 50°C. Moisture content, water activity, colour, bulk density, and total phenolic content (TPC) were determined in samples. Freeze dried sample had significantly (p<0.05) lower moisture content, water activity, bulk density, total colour difference and browning index than hot air dried samples. For antioxidant activity, the results showed hot-air drying at 70°C effected highest TPC similar to freeze drying.


1998 ◽  
Vol 51 (3) ◽  
pp. 905-911 ◽  
Author(s):  
J. M. Saiter ◽  
N. Delahaye ◽  
A. Bardat ◽  
E. Chatenet

LWT ◽  
2019 ◽  
Vol 107 ◽  
pp. 236-242 ◽  
Author(s):  
Qingfa Wang ◽  
Song Li ◽  
Xue Han ◽  
Yuanying Ni ◽  
Dandan Zhao ◽  
...  

2016 ◽  
Vol 12 (6) ◽  
pp. 599-606 ◽  
Author(s):  
Flávia Daiana Montanuci ◽  
Raphaela Mulato Cavalcante ◽  
Camila Augusto Perussello ◽  
Luiz Mario de Matos Jorge

Abstract The study of process kinetics may aid the design and optimization of drying systems. This paper evaluated the influence of drying temperature (40, 60 and 80 °C) on the moisture content, drying rate, density, shrinkage and breakage of maize dried in two different dryers: oven and silo dryer. In both dryers, the temperature increase reduced drying time, final moisture content and shrinkage of the grains, however increased breakage. Drying rate was higher in the oven (6.4×10−4±2.3×10−4s−1 versus 5.4×10−4±1.2×10−4s−1), while shrinkage (15.2±4.7 % versus 24.4±5.6 %) and density increase (16.6±5.9 % versus 33.4±5.8 %) were more intense in the silo. There was a large release of husk in the silo dryer and the moisture content was slightly smaller in the lower layers respective to the upper ones.


The study is aimed experimentally and compared with the theoretical results of drying kinetics of Nagpur orange fruit dried in a hot air electrical dryer. Orange fruit is highly perishable and needs to be consumed or processed immediately after harvest. Drying or dehydration is one of the most practical methods of preserving food products. Therefore, thin layer drying characteristics of falling rate of Nagpur orange are determined experimentally under different conditions of drying air temperatures, relative humidity and air velocities for different moisture contents. Thin layer models like Wang and Singh, Page and Henderson have been compared with Experimental results. The knowledge of drying kinetics helps for identification of exact drying time and air flow velocity for different moisture content. Here drying operation is carried out at a velocity of 1m/sec and 1.25 m/sec for different temperature of 55°C, 65°C and 75°C. This analysis reveals that drying temperature has a more significant effect on moisture removal while velocity has the least effect. Drying rate is found to increase with the increase in drying temperature and reduce with drying time. Experimental data is statistically correlated by plotting the drying characteristics curve. The analysis reveals that Wang and Singh's model is a better model to explain the drying behavior of Nagpur Orange fruit (R2=0.9888).


2020 ◽  
pp. 119-136
Author(s):  
Bobby Shekarau ◽  
Riyang Zakka ◽  
Tswenma Tsokwa ◽  
Kenneth Yuguda ◽  
Udom Okon

Due to renewed interest in fruit residue application, cashew apple pomace and other fruit pomace are receiving unparallel attention as substitute for food ingredient or food enrichment options. This necessitates this study to investigate drying as vital approach in preserving and conditioning cashew apple pomace. In this study, cashew apple fruits were blended in fruit blender and filtered through 150 microns filter; the filtrate was further tightened in a fabric material and pressed with manual hydraulic press to further express the juice in it. The pomace was stored in a refrigerator at 3 ?C for 18 h to homogenise the moisture. The pomace was divided into nine equal weights, a portion was fed into hot air oven dryer at 60 ?C and constant circulating air velocity of 2.2 m/s, the changes in mass was measured using digital mass balance after every 10 minutes. The procedure was repeated at 70 and 80 ?C and in triplicate; in each case the mass of the samples was measured. It was found that cashew pomace dry under a single falling rate period, effective moisture diffusivity increased with increasing drying temperature and ranges from 9.02015?10-9 to 2.12177?10-8, activation energy was estimated as 41.880 kJ/K, specific drying energy consumption decreased with increasing drying temperature and ranges from 24.1 to 45.3 MJ/kg. Our proposed drying model was found to adequately simulate the drying kinetics of cashew apple pomace.


2019 ◽  
Author(s):  
Zhian Zheng ◽  
Dalong Jiang ◽  
Lei Gao ◽  
Guangfei Zhu ◽  
Yawen Lin

Foods ◽  
2013 ◽  
Vol 2 (2) ◽  
pp. 170-182 ◽  
Author(s):  
Jamshid Rahimi ◽  
Ashutosh Singh ◽  
Peter Adewale ◽  
Akinbode Adedeji ◽  
Michael Ngadi ◽  
...  

2020 ◽  
Vol 92 (9) ◽  
pp. 1332-1332
Author(s):  
P. Levin ◽  
V. Meunier ◽  
S. Palzer ◽  
S. Heinrich

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