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Zang Z, Wan F, Jia H, Ma G, Xu Y, Zhao Q, Wu B, Lu H, Huang X. Developing Effective Radio Frequency Vacuum Drying Processes for Moutan Cortex: Effect on Moisture Migration, Drying Kinetics, Physicochemical Quality, and Microstructure. Foods 2024; 13:2294. [PMID: 39063380 PMCID: PMC11275577 DOI: 10.3390/foods13142294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 07/08/2024] [Accepted: 07/19/2024] [Indexed: 07/28/2024] Open
Abstract
This study aims to maximize the post-harvest quality of Moutan Cortex and reduce energy consumption. Radio frequency vacuum (RFV) technology was used to dehydrate Moutan Cortex in this study to investigate the effects of different drying temperatures, plate spacing, and vacuum degree on the drying kinetics, physicochemical quality, and microstructure of Moutan Cortex. The results showed that RFV drying shortened the dehydration time of the Moutan Cortex by 10.71-28.57% and increased the drying rate by 15.79-54.39% compared to hot-air drying. The best color (∆E = 6.08 ± 0.28, BI = 26.97 ± 0.98) and relatively high retention of polysaccharides, total phenolics, total flavonoids, antioxidant properties, paeonol, gallic acid, paeoniflorin, and benzoylpaeoniflorin contents were observed in the dried products of Moutan Cortex at a drying temperature of 50 °C, spacing of 90 mm, and vacuum of 0.025 MPa. Analyzing the microstructure, it was found that RFV drying could effectively inhibit the shrinkage and collapse of the cellular structure, and a regular and loose honeycomb pore structure appeared inside the samples, which contributed to the rapid migration of the internal moisture. This study can provide a theoretical reference basis for the selection and application of industrialized processing methods of high-quality Moutan Cortex.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Xiaopeng Huang
- College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China; (Z.Z.); (F.W.); (H.J.); (G.M.)
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2
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Zang Z, Wan F, Ma G, Xu Y, Wang T, Wu B, Huang X. Enhancing peach slices radio frequency vacuum drying by combining ultrasound and ultra-high pressure as pretreatments: Effect on drying characteristics, physicochemical quality, texture and sensory evaluation. ULTRASONICS SONOCHEMISTRY 2024; 103:106786. [PMID: 38309049 PMCID: PMC10847764 DOI: 10.1016/j.ultsonch.2024.106786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/21/2024] [Accepted: 01/24/2024] [Indexed: 02/05/2024]
Abstract
To maximally maintain fruits and vegetables quality after harvest, this study used ultrasonic (US) and ultra-high pressure (UHP) techniques as pretreatments for radio frequency vacuum (RFV) drying of peach slices, and investigated the effects of different pretreatments (US, UHP, UHP-US, and US-UHP) on drying characteristics, physicochemical qualities, texture properties, and sensory evaluation of peach slices. Results showed that the drying rate was increased by 15.79 ∼ 54.39 % and the contents of pectin, hemicellulose, total phenolic, total flavonoid, phenolic acids, individual sugar annd antioxidant of the samples were significantly increased after US combined with UHP pretreatment (P < 0.05). US-UHP + RFV dried peach slices obtained brighter color, better texture attributes of hardness, cohesiveness, chewiness, springiness, and resilience. The dehydrated samples pretreated by UHP-US had the best overall acceptance, appearance, and crispness with lower off-odor and sourness compared to the dehydrated peach slices with US and UHP pretreatment. Notably, the highest cellulose and organic acids were found in dehydrated peach slices by control, followed by samples US, and samples with UHP pretreatment. The microstructure showed that the internal organization of peach slices appeared as uniform and regular honeycomb porous structure after US-UHP pretreatment. The findings may provide theoretical reference for the development of energy-efficient and high-quality drying technology for fruits and vegetables.
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Affiliation(s)
- Zepeng Zang
- College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China
| | - Fangxin Wan
- College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China
| | - Guojun Ma
- College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China
| | - Yanrui Xu
- College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China
| | - Tongxun Wang
- College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China
| | - Bowen Wu
- College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China
| | - Xiaopeng Huang
- College of Mechanical and Electrical Engineering, Gansu Agricultural University, Lanzhou 730070, China.
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Turan S, Elik Demir A, Göğüş F, Yanık DK. Hot-Air-Assisted Radiofrequency Drying of Olive Pomace and Its Effect on the Quality of Olive Pomace Oil. Foods 2023; 12:3515. [PMID: 37761225 PMCID: PMC10527796 DOI: 10.3390/foods12183515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 09/18/2023] [Accepted: 09/20/2023] [Indexed: 09/29/2023] Open
Abstract
In this study, the drying of olive pomace in a hot-air-assisted radio frequency system (HA-RF) was conducted, and its effects on crude olive pomace oil quality were investigated. In this respect, the effects of radiofrequency electrode distance (90, 105 and 120 mm), sample thickness (2.5, 5, 7.5 and 10 cm) and compaction density (~0.45, ~0.60 and ~0.82 g/cm3) on drying rate have been evaluated. The best drying, with a higher drying efficiency, was obtained with 1 kg of sample weight and a 10 cm product thickness, ~0.45 g/cm3 compaction density and 105 mm electrode distance. Moreover, the results showed that the compaction density significantly affects the drying rate. The drying time was prolonged by approximately four times by increasing the compaction density from ~0.45 to ~0.82 g/cm3. The drying rate of olive pomace in HA-RF drying was compared with drying performed using hot air (HA) and radiofrequency (RF). The results revealed that HA-RF application reduced the drying time by almost 1.7 times compared to hot air drying and by about 2.7 times compared to radiofrequency. The peroxide value, free fatty acid content, p-anisidine value, polyaromatic hydrocarbon content, L*, a*, b*, chlorophyll and total carotenoid content of the oil extracted from the olive pomace dried under the best drying conditions were 1.09%, 12.2 meq O2/kg oil, 3.01, <1 ppb, 38.6, 7.5, 62.56, 105.25 mg pheophytin a/kg oil, 2.85 mg/kg oil, respectively. The drying of olive pomace in a hot-air-assisted radio frequency system could be an alternative way to ensure the safe and rapid drying of olive pomace.
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Affiliation(s)
- Sinem Turan
- Department of Food Engineering, Engineering Faculty, University of Gaziantep, Gaziantep 27310, Türkiye; (S.T.); (F.G.)
| | - Aysel Elik Demir
- Department of Food Technology, Vocational School of Technical Sciences at Mersin Tarsus Organized Industrial Zone, Tarsus University, Mersin 33100, Türkiye;
| | - Fahrettin Göğüş
- Department of Food Engineering, Engineering Faculty, University of Gaziantep, Gaziantep 27310, Türkiye; (S.T.); (F.G.)
| | - Derya Koçak Yanık
- Department of Food Engineering, Faculty of Agriculture, Eskişehir Osmangazi University, Eskişehir 26160, Türkiye
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Zheng Z, Wei S, Xie W, Ren L, Fan B, Fu H, Yang D. Determination and comparison of effective moisture diffusivity of carrot (core and cortex) during hot air drying. J FOOD PROCESS ENG 2022. [DOI: 10.1111/jfpe.14236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Zhaohui Zheng
- College of Engineering China Agricultural University Beijing China
| | - Shuo Wei
- College of Engineering China Agricultural University Beijing China
- College of Tobacco Science Henan Agricultural University Henan Zhengzhou China
| | - Weijun Xie
- College of Engineering China Agricultural University Beijing China
- College of Mechanical and Electronic Engineering Nanjing Forestry University Nanjing China
| | - Liuyang Ren
- College of Engineering China Agricultural University Beijing China
| | - Ben Fan
- College of Engineering China Agricultural University Beijing China
| | - Hanyu Fu
- College of Engineering China Agricultural University Beijing China
| | - Deyong Yang
- College of Engineering China Agricultural University Beijing China
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Thermal and Dielectric Properties of Wolfberries as Affected by Moisture Content and Temperature Associated with Radio Frequency and Microwave Dehydrations. Foods 2022; 11:foods11233796. [PMID: 36496604 PMCID: PMC9738072 DOI: 10.3390/foods11233796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/18/2022] [Accepted: 11/22/2022] [Indexed: 11/26/2022] Open
Abstract
Knowledge of the thermal and dielectric properties of wolfberries is essential for understanding the heat transfer and the interaction between the electromagnetic field (10-3000 MHz) and the sample during radio frequency (RF) and microwave (MW) drying. The thermal and dielectric properties of wolfberries were determined as influenced by moisture content from 15.1% to 75.2%, w.b.) and temperature from 25 to 85 °C. The results showed that as the moisture content increased from 15.1% to 75.2% (w.b.), the true density of wolfberries decreased, but the specific heat capacity and thermal conductivity increased with increasing temperature and moisture content. The dielectric properties (DPs) of wolfberries decreased with increasing frequency from 10 to 3000 MHz. The dielectric constant increased with increasing temperature at lower a moisture content (below 45% w.b.) but decreased with increasing temperature at a high moisture content (above 60% w.b.). The cubic and quadratic polynomial models (R2 = 0.977 - 0.997) were best for fitting the dielectric constant and loss factor at four representative frequencies of 27, 40, 915, and 2450 MHz, respectively. The penetration depth increased with the decreased frequency, temperature, and moisture content, and was greater at RF frequencies than MW range, making the RF heating more effective for drying bulk wolfberries. These findings offered essential data before optimizing RF or MW dehydration protocols for wolfberries via computer simulation.
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Chen X, Liu Y, Zhang R, Zhu H, Li F, Yang D, Jiao Y. Radio Frequency Drying Behavior in Porous Media: A Case Study of Potato Cube with Computer Modeling. Foods 2022; 11:3279. [PMID: 37431029 PMCID: PMC9602172 DOI: 10.3390/foods11203279] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/06/2022] [Accepted: 10/06/2022] [Indexed: 08/27/2023] Open
Abstract
To study the mechanism of heat and mass transfer in porous food material and explore its coupling effect in radio frequency (RF) drying processes, experiments were conducted with potato cubes subjected to RF drying. COMSOL Multiphysics® package was used to establish a numerical model to simulate the heat and mass transfer process in the potato cube and solved with finite element method. Temperature history at the sample center and the heating pattern after drying was validated with experiment in a 27.12 MHz RF heating system. Results showed the simulation results were in agreement with experiments. Furthermore, the temperature distribution and water vapor concentration distribution were correspondent with water distribution in the sample after RF drying. The water concentration within the food volume was non-uniform with a higher water concentration than the corner, the maximum difference of which was 0.03 g·cm-3. The distribution of water vapor concentration in the sample was similar to that of water content distribution since a pressure gradient from center to corner allowed the mass transfer from the sample to the surrounding in the drying process. In general, the moisture distribution in the sample affected the temperature and water vapor concentration distribution since the dielectric properties of the sample were mainly dependent on its moisture content during a drying process. This study reveals the mechanism of RF drying of porous media and provides an effective approach for analyzing and optimizing the RF drying process.
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Affiliation(s)
- Xiangqing Chen
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Engineering Research Center of Food Thermal-Processing Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Yu Liu
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Engineering Research Center of Food Thermal-Processing Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Ruyi Zhang
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Engineering Research Center of Food Thermal-Processing Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Huacheng Zhu
- College of Electronics and Information Engineering, Sichuan University, Chengdu 610065, China
| | - Feng Li
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Engineering Research Center of Food Thermal-Processing Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Deyong Yang
- College of Engineering, China Agricultural University, Beijing 100083, China
| | - Yang Jiao
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
- Engineering Research Center of Food Thermal-Processing Technology, Shanghai Ocean University, Shanghai 201306, China
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Xiong Z, Shi T, Jin W, Bao Y, Monto AR, Yuan L, Gao R. Gel performance of surimi induced by various thermal technologies: A review. Crit Rev Food Sci Nutr 2022; 64:3075-3090. [PMID: 36193875 DOI: 10.1080/10408398.2022.2130154] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Heating is a vital step in the gelation of surimi. Conventional water bath heating (WB) has the advantages of easy operation and low equipment requirements. However, the slow heat penetration during WB may lead to poor gel formation or gels prone to deterioration, especially with one-step heating. The two-step WB is time-consuming, and a large amount of water used tends to cause environmental problems. This review focuses on key factors affecting the quality of surimi gels in various heating technologies, such as surimi protein structure, chemical forces, or the activity of endogenous enzymes. In addition, the relationships between these factors and the gel performance of surimi under various heating modes are discussed by analyzing the heating temperature and heating rate. Compared with WB, the gel performance can be improved by controlling the heating conditions of microwave heating and ohmic heating, which are mainly achieved by changing the molecular structure of myofibrillar proteins or the activity of endogenous enzymes in surimi. Nevertheless, the novel thermal technologies still face several limitations and further research is needed to realize large-scale industrial production. This review provides ideas and directions for developing heat-induced surimi products with excellent gel properties.
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Affiliation(s)
- Zhiyu Xiong
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Tong Shi
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Wengang Jin
- Bio-resources Key Laboratory of Shaanxi Province, School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, China
| | - Yulong Bao
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Abdul Razak Monto
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Li Yuan
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Ruichang Gao
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
- Bio-resources Key Laboratory of Shaanxi Province, School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, China
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8
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Lin Q, Ren A, Liu R, Xing Y, Yu X, Jiang H. Flavor properties of Chinese noodles processed by dielectric drying. Front Nutr 2022; 9:1007997. [PMID: 36245479 PMCID: PMC9558107 DOI: 10.3389/fnut.2022.1007997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 09/15/2022] [Indexed: 11/13/2022] Open
Abstract
Volatile organic compounds (VOCs) significantly impact food flavor. In this work, Electron nose (E-nose), head space solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), and head space-gas chromatography-ion mobility spectrometry (HS-GC-IMS) techniques were applied to analyze different drying effects: microwave, hot air, and radio frequency on the aroma of Chinese noodles. E-nose analysis suggests that aromatic differences are mainly from broad range-methane. HS-SPME-GC-MS and HS-GC-IMS identified 47 and 26 VOCs in the fresh and dried noodles, respectively. The VOCs in the dried noodles were mainly aldehydes, alcohols, and esters. Drying significantly reduced the types of VOCs in Chinese dried noodles. Microwave dried noodles exhibited the strongest aroma after the shortest time of treatment, suggesting microwave drying may be the best drying method for noodles. Using aromatic analysis, this paper provides useful information for understanding the flavor of flour products and offers new ideas for drying noodles.
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Affiliation(s)
- Qian Lin
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Aiqing Ren
- Institute of Food Research, Hezhou University, Guangxi, China
| | - Rui Liu
- Cereal Industrial Technology Academy, Hebei Jinshahe Flour and Noodle Group/Hebei Cereal Food Processing Technology Innovation Centre, Xingtai, China
| | - Yanan Xing
- Cereal Industrial Technology Academy, Hebei Jinshahe Flour and Noodle Group/Hebei Cereal Food Processing Technology Innovation Centre, Xingtai, China
| | - Xiuzhu Yu
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Hao Jiang
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
- Engineering Research Center of Grain and Oil Functionalized Processing, Universities of Shaanxi Province, Yangling, China
- *Correspondence: Hao Jiang, ;
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9
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Sterilizing Ready-to-Eat Poached Spicy Pork Slices Using a New Device: Combined Radio Frequency Energy and Superheated Water. Foods 2022; 11:foods11182841. [PMID: 36140967 PMCID: PMC9497799 DOI: 10.3390/foods11182841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 09/04/2022] [Accepted: 09/08/2022] [Indexed: 11/30/2022] Open
Abstract
In this study, a new device was used to inactivate G. stearothermophilus spores in ready-to-eat (RTE) poached spicy pork slices (PSPS) applying radio frequency (RF) energy (27.12 MHz, 6 kW) and superheated water (SW) simultaneously. The cold spot in the PSPS sample was determined. The effects of electrode gap and SW temperature on heating rate, spore inactivation, physiochemical properties (water loss, texture, and oxidation), sensory properties, and SEM of samples were investigated. The cold spot lies in the geometric center of the soup. The heating rate increased with increasing electrode gap and hit a peak under 190 mm. Radio frequency combined superheated water (RFSW) sterilization greatly decreased the come-up time (CUT) compared with SW sterilization, and a 5 log reduction in G. stearothermophilus spores was achieved. RFSW sterilization under 170 mm electrode gap reduced the water loss, thermal damage of texture, oxidation, and tissues and cells of the sample, and kept a better sensory evaluation. RFSW sterilization has great potential in solid or semisolid food processing engineering.
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Kemal E, Özbek HN, Göğüş F, Yanık DK. Hot air-assisted radio frequency drying of grated potato (Solanum tuberosum L.): Drying behavior and the associated effect on characteristics of potato flour. J Food Sci 2022; 87:4068-4081. [PMID: 35975880 DOI: 10.1111/1750-3841.16265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 05/16/2022] [Accepted: 07/04/2022] [Indexed: 11/27/2022]
Abstract
In this study, drying of grated potato in a hot air-assisted radio frequency system (HA-RF) and the associated effects on the final potato flour quality were studied. The drying behavior of the grated potatoes at different electrode distances (70-90 mm) and sample thickness (2-4 cm) was investigated. The safe drying (without burning tendency) of the maximum amount of sample (1000 g) in a reasonable drying time was carried out at 80 mm of electrode gap and 4 cm of sample thickness. HA-RF drying kinetics were studied and compared with hot air (HA) and radio frequency (RF) (without hot air) drying methods. HA-RF drying increased drying rate and shortened drying time by about 58% and 70% compared to HA and RF drying, respectively. The properties of the final potato flour obtained after HA-RF drying were also compared with those produced by RF, HA, and freeze drying. The flour obtained by HA-RF was superior to RF and HA dried samples with better retention of cellular microstructure and color. The drying method significantly affected the functional properties, thermal characteristics, pasting properties, and other characteristics of potato flours. PRACTICAL APPLICATION: HA-RF as an alternative drying technology was used for the first time to produce potato flour. The functional, thermal, and structural properties of the HA-RF dried product were compared with those dried by HA, RF, and freeze drying. The results of this study ensured very useful information for the use of potato flour obtained by different drying methods in the development of products with specific functional and rheological properties.
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Affiliation(s)
- Ezgi Kemal
- Department of Food Engineering, University of Gaziantep, Gaziantep, Turkey
| | - Hatice Neval Özbek
- Department of Food Engineering, University of Gaziantep, Gaziantep, Turkey
| | - Fahrettin Göğüş
- Department of Food Engineering, University of Gaziantep, Gaziantep, Turkey
| | - Derya Koçak Yanık
- Department of Food Engineering, University of Gaziantep, Gaziantep, Turkey
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Influence of Radio Frequency Heating on the Pasteurization and Drying of Solid-State Fermented Wolfiporia cocos Products. Foods 2022; 11:foods11121766. [PMID: 35741963 PMCID: PMC9222229 DOI: 10.3390/foods11121766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/19/2022] [Accepted: 06/10/2022] [Indexed: 11/17/2022] Open
Abstract
Rice bran and soybean residue are high in nutrients and active ingredients. They are used as media in the solid-state fermentation of Wolfiporia cocos. They not only reduce raw material costs, but also raise the economic value and applications of soybean residues and rice bran. After 30 days of fermentation, the moisture content (w.b.) of the W. cocos product was approximately 40%, requiring it to be pasteurized and dried later. The objective of this research is to use radio frequency (RF) rapid heating technology to pasteurize and dry the solid-state fermented product. A 500 g bag of solid-state fermented W. cocos product took only 30 and 200 s at the RF electrode gap of 15 cm to pasteurize and reduce the moisture content (w.b.) below 15%, respectively; therefore, the methods can be used instead of the traditional 60 min autoclave sterilization and 100 min hot air drying at 45 °C. After RF treatment, the fermented W. cocos product was white, indicating that browning was prevented; the product contained 5.03% mycelium, 9.83% crude polysaccharide, 4.43% crude triterpene, 3.54 mg gallic acid equivalent/g dry weight (DW) of total polyphenols, and 0.38 mg quercetin equivalent/g DW of flavonoid contents and showed a good antioxidant capacity.
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12
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Characteristics and Quality Analysis of Radio Frequency-Hot Air Combined Segmented Drying of Wolfberry (Lycium barbarum). Foods 2022; 11:foods11111645. [PMID: 35681395 PMCID: PMC9180603 DOI: 10.3390/foods11111645] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/26/2022] [Accepted: 05/30/2022] [Indexed: 11/16/2022] Open
Abstract
To overcome the problems of a long conventional drying time, low energy efficiency, and poor product quality, a segmented drying approach was developed for fresh wolfberry (Lycium barbarum) using a radio frequency (RF)-hot air drying process, which was investigated under different parameters of plate spacing (80, 90, 100 mm), vacuum degree (0.015, 0.025, 0.035 Mpa), and hot air temperature (50, 55, 60 °C). Analysis of the wolfberry’s drying characteristics, comprehensive quality, and microstructure indicated that: combined drying was faster and less time-consuming than natural drying or hot air drying, and components such as polysaccharides, ascorbic acid, and betaine in wolfberries were effectively retained. Based on the acceptable drying rate, stable temperature application, and avoidance of arcing effects, the optimal combined segmented drying parameters were determined to be as follows: a plate spacing of 90 mm, vacuum degree of 0.025 MPa, and air temperature of 55 °C. For the dried wolfberries under these conditions, the total drying time was 17 h and the berries had an improved comprehensive quality, the content of total soluble sugars was 0.62 g/g, total phenol was 10.01 mg/g, total flavonoids was 2.60 mg/g, VC was 3.18 mg/100 g, betaine was 3.48%, oxidation resistance represented by an inhibition rate was 66.14%, color was better, and rehydration rate was 48.56%. The microstructure was more regular because of the special dielectric heating characteristics of RF vacuuming. Despite the differing drying characteristics of individual materials, the overall RF-hot air combined drying process was found to achieve high-quality dehydration of wolfberries.
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Lin B, Guan X, Huang Z, Wang P, Jiang H, Xu R, Jiao Q, Li R, Wang S. Improvement of radio frequency heating uniformity in wheat kernels with aluminum foil sheets covered on rectangular container walls. J FOOD ENG 2022. [DOI: 10.1016/j.jfoodeng.2021.110768] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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14
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Topcam H, Gogus F, Ozbek HN, Elik A, Yanik DK, Dalgic AC, Erdogdu F. Hot air‐assisted radio frequency drying of apricots: Mathematical modeling study for process design. J Food Sci 2022; 87:764-779. [DOI: 10.1111/1750-3841.16021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 10/25/2021] [Accepted: 11/30/2021] [Indexed: 12/19/2022]
Affiliation(s)
- Huseyin Topcam
- Department of Food Engineering Ankara University Ankara Turkey
| | - Fahrettin Gogus
- Department of Food Engineering Gaziantep University Gaziantep Turkey
| | | | - Aysel Elik
- Department of Food Engineering Gaziantep University Gaziantep Turkey
| | - Derya Kocak Yanik
- Department of Food Engineering Gaziantep University Gaziantep Turkey
| | - Ali Coskun Dalgic
- Department of Food Engineering Gaziantep University Gaziantep Turkey
| | - Ferruh Erdogdu
- Department of Food Engineering Ankara University Ankara Turkey
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15
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Özbek HN. Radio frequency-assisted hot air drying of carrots for the production of carrot powder: Kinetics and product quality. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.112332] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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16
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Liu J, Wang P, Wang S. Effects of various directional movements of milled rice on radio frequency heating uniformity. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.112316] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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17
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Elik A. Hot air-assisted radio frequency drying of black carrot pomace: Kinetics and product quality. INNOV FOOD SCI EMERG 2021. [DOI: 10.1016/j.ifset.2021.102800] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mao Y, Wang S. Recent developments in radio frequency drying for food and agricultural products using a multi-stage strategy: a review. Crit Rev Food Sci Nutr 2021; 63:2654-2671. [PMID: 34583556 DOI: 10.1080/10408398.2021.1978925] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Radio frequency (RF) drying is an emerging technology for food and agricultural products, holding features of rapid, uniform, stable, and volumetric heating, high energy efficiency, and moisture leveling. However, the RF drying with a single stage commonly has drawbacks of unexpected product quality, non-uniform moisture distribution, and prolonged drying time. The multi-stage drying approach could overcome the shortcomings of one-stage strategy accordingly by applying different drying methods or operating parameter values in each phase separately. This review describes the principle of RF heating, presents the typical systems and superiorities of RF drying, and provides a comprehensive overview on recent development in applications of both the one-stage and the multi-stage RF drying, and analysis of drying characteristics and merits for different types of the two-stage strategy. This review finally proposes recommendations for future studies in improving and optimizing the existing RF drying protocols and scaling up them to industrial applications.
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Affiliation(s)
- Yuxiao Mao
- College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Shaojin Wang
- College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling, Shaanxi, China.,Department of Biological Systems Engineering, Washington State University, Pullman, Washington, USA
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Hao Y, Mao Y, Hou L, Wang S. Developing a rotation device in radio frequency systems for improving the heating uniformity in granular foods. INNOV FOOD SCI EMERG 2021. [DOI: 10.1016/j.ifset.2021.102751] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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