Pulsed Vacuum Drying of Pepper (<i>Capsicum annuum</i> L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality Attributes
With a high moisture content, fresh peppers are perishable and rot easily. Drying is essential for shelf-life extension. The natural thin wax layer on the pepper surface hinders moisture transfer. Traditionally, chemical dipping or mechanical pricking is used to remove this wax layer. However, in ch...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-01-01
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| Series: | Foods |
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| Online Access: | https://www.mdpi.com/2304-8158/11/3/318 |
| _version_ | 1797487859865747456 |
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| author | Zhihua Geng Xiao Huang Jun Wang Hongwei Xiao Xuhai Yang Lichun Zhu Xiaochen Qi Qian Zhang Bin Hu |
| author_facet | Zhihua Geng Xiao Huang Jun Wang Hongwei Xiao Xuhai Yang Lichun Zhu Xiaochen Qi Qian Zhang Bin Hu |
| author_sort | Zhihua Geng |
| collection | DOAJ |
| description | With a high moisture content, fresh peppers are perishable and rot easily. Drying is essential for shelf-life extension. The natural thin wax layer on the pepper surface hinders moisture transfer. Traditionally, chemical dipping or mechanical pricking is used to remove this wax layer. However, in chemical dipping, chemical residues can trigger food-safety issues, while the low efficiency of mechanical pricking hinders its industrial application. Feasible pretreatment methods are advantageous for industrial use. Here, an emerging pretreatment technique (high-humidity hot-air impingement blanching, HHAIB) was used for peppers before drying and its effects on drying characteristics, microstructure, and polyphenol oxidase (PPO) activity were explored. The impact of drying temperature on color parameters and red pigment content of pulsed-vacuum-dried peppers was also evaluated. PPO activity was reduced to less than 20% after blanching at 110 °C for 60 s. HHAIB reduced drying time and PPO activity and promoted chemical-substance release. Effective water diffusivity was highest (5.01 × 10<sup>−10</sup> m<sup>2</sup>/s) after blanching at 110 °C for 90 s, and the brightness value and red pigment content were highest (9.94 g/kg) at 70 °C. HHAIB and pulsed vacuum drying are promising pretreatment and drying methods for enhancing the drying rate and quality of red peppers. |
| first_indexed | 2024-03-09T23:53:49Z |
| format | Article |
| id | doaj.art-af32b6c76bde4c54b9becb5e31cfd999 |
| institution | Directory Open Access Journal |
| issn | 2304-8158 |
| language | English |
| last_indexed | 2024-03-09T23:53:49Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Foods |
| spelling | doaj.art-af32b6c76bde4c54b9becb5e31cfd9992023-11-23T16:28:53ZengMDPI AGFoods2304-81582022-01-0111331810.3390/foods11030318Pulsed Vacuum Drying of Pepper (<i>Capsicum annuum</i> L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality AttributesZhihua Geng0Xiao Huang1Jun Wang2Hongwei Xiao3Xuhai Yang4Lichun Zhu5Xiaochen Qi6Qian Zhang7Bin Hu8Engineering Research Center for Production Mechanization of Oasis Special Economic Crop, College of Mechanical and Electrical Engineering, Ministry of Education, Shihezi University, Shihezi 832000, ChinaEngineering Research Center for Production Mechanization of Oasis Special Economic Crop, College of Mechanical and Electrical Engineering, Ministry of Education, Shihezi University, Shihezi 832000, ChinaEngineering Research Center for Production Mechanization of Oasis Special Economic Crop, College of Mechanical and Electrical Engineering, Ministry of Education, Shihezi University, Shihezi 832000, ChinaEngineering Research Center for Production Mechanization of Oasis Special Economic Crop, College of Mechanical and Electrical Engineering, Ministry of Education, Shihezi University, Shihezi 832000, ChinaEngineering Research Center for Production Mechanization of Oasis Special Economic Crop, College of Mechanical and Electrical Engineering, Ministry of Education, Shihezi University, Shihezi 832000, ChinaEngineering Research Center for Production Mechanization of Oasis Special Economic Crop, College of Mechanical and Electrical Engineering, Ministry of Education, Shihezi University, Shihezi 832000, ChinaEngineering Research Center for Production Mechanization of Oasis Special Economic Crop, College of Mechanical and Electrical Engineering, Ministry of Education, Shihezi University, Shihezi 832000, ChinaEngineering Research Center for Production Mechanization of Oasis Special Economic Crop, College of Mechanical and Electrical Engineering, Ministry of Education, Shihezi University, Shihezi 832000, ChinaXinjiang Production and Construction Corps Key Laboratory of Modern Agricultural Machinery, Shihezi 832000, ChinaWith a high moisture content, fresh peppers are perishable and rot easily. Drying is essential for shelf-life extension. The natural thin wax layer on the pepper surface hinders moisture transfer. Traditionally, chemical dipping or mechanical pricking is used to remove this wax layer. However, in chemical dipping, chemical residues can trigger food-safety issues, while the low efficiency of mechanical pricking hinders its industrial application. Feasible pretreatment methods are advantageous for industrial use. Here, an emerging pretreatment technique (high-humidity hot-air impingement blanching, HHAIB) was used for peppers before drying and its effects on drying characteristics, microstructure, and polyphenol oxidase (PPO) activity were explored. The impact of drying temperature on color parameters and red pigment content of pulsed-vacuum-dried peppers was also evaluated. PPO activity was reduced to less than 20% after blanching at 110 °C for 60 s. HHAIB reduced drying time and PPO activity and promoted chemical-substance release. Effective water diffusivity was highest (5.01 × 10<sup>−10</sup> m<sup>2</sup>/s) after blanching at 110 °C for 90 s, and the brightness value and red pigment content were highest (9.94 g/kg) at 70 °C. HHAIB and pulsed vacuum drying are promising pretreatment and drying methods for enhancing the drying rate and quality of red peppers.https://www.mdpi.com/2304-8158/11/3/318high-humidity hot-air impingement blanching (HHAIB)pulsed vacuum drying (PVD)drying characteristicskinetic modelingtransmission electron microscopy (TEM)polyphenol oxidase activity |
| spellingShingle | Zhihua Geng Xiao Huang Jun Wang Hongwei Xiao Xuhai Yang Lichun Zhu Xiaochen Qi Qian Zhang Bin Hu Pulsed Vacuum Drying of Pepper (<i>Capsicum annuum</i> L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality Attributes Foods high-humidity hot-air impingement blanching (HHAIB) pulsed vacuum drying (PVD) drying characteristics kinetic modeling transmission electron microscopy (TEM) polyphenol oxidase activity |
| title | Pulsed Vacuum Drying of Pepper (<i>Capsicum annuum</i> L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality Attributes |
| title_full | Pulsed Vacuum Drying of Pepper (<i>Capsicum annuum</i> L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality Attributes |
| title_fullStr | Pulsed Vacuum Drying of Pepper (<i>Capsicum annuum</i> L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality Attributes |
| title_full_unstemmed | Pulsed Vacuum Drying of Pepper (<i>Capsicum annuum</i> L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality Attributes |
| title_short | Pulsed Vacuum Drying of Pepper (<i>Capsicum annuum</i> L.): Effect of High-Humidity Hot Air Impingement Blanching Pretreatment on Drying Kinetics and Quality Attributes |
| title_sort | pulsed vacuum drying of pepper i capsicum annuum i l effect of high humidity hot air impingement blanching pretreatment on drying kinetics and quality attributes |
| topic | high-humidity hot-air impingement blanching (HHAIB) pulsed vacuum drying (PVD) drying characteristics kinetic modeling transmission electron microscopy (TEM) polyphenol oxidase activity |
| url | https://www.mdpi.com/2304-8158/11/3/318 |
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