Effect of Thermal and Non-Thermal Technologies on Kinetics and the Main Quality Parameters of Red Bell Pepper Dried with Convective and Microwave–Convective Methods

The drying process preserves the surplus of perishable food. However, to obtain a goodquality final product, different pretreatments are conducted before drying. Thus, the aim of the study was the evaluation of the effect of thermal (blanching treatments with hot water) and non-thermal technologies...

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Bibliographic Details
Main Authors: Dadan, M. (Author), Kaveh, M. (Author), Nowacka, M. (Author), Rybak, K. (Author), Wiktor, A. (Author), Witrowa-Rajchert, D. (Author)
Format: Article
Language:English
Published: MDPI 2022
Subjects:
Online Access:View Fulltext in Publisher
LEADER 03392nam a2200505Ia 4500
001 10.3390-molecules27072164
008 220425s2022 CNT 000 0 und d
020 |a 14203049 (ISSN) 
245 1 0 |a Effect of Thermal and Non-Thermal Technologies on Kinetics and the Main Quality Parameters of Red Bell Pepper Dried with Convective and Microwave–Convective Methods 
260 0 |b MDPI  |c 2022 
856 |z View Fulltext in Publisher  |u https://doi.org/10.3390/molecules27072164 
520 3 |a The drying process preserves the surplus of perishable food. However, to obtain a goodquality final product, different pretreatments are conducted before drying. Thus, the aim of the study was the evaluation of the effect of thermal (blanching treatments with hot water) and non-thermal technologies (pulsed electric field (PEF) and ultrasound (US)) on the kinetics of the drying process of red bell pepper. The convective and microwave–convective drying were compared based on quality parameters, such as physical (water activity, porosity, rehydration rate, and color) and chemical properties (total phenolic content, total carotenoids content, antioxidant activity, and total sugars content). The results showed that all of the investigated methods reduced drying time. However, the most effective was blanching, followed by PEF and US treatment, regardless of the drying technique. Non-thermal methods allowed for better preservation of bioactive compounds, such as vitamin C in the range of 8.2% to 22.5% or total carotenoid content in the range of 0.4% to 48%, in comparison to untreated dried material. Moreover, PEF-treated red bell peppers exhibited superior antioxidant activity (higher of about 15.2–30.8%) when compared to untreated dried samples, whereas sonication decreased the free radical scavenging potential by ca. 10%. In most cases, the pretreatment influenced the physical properties, such as porosity, color, or rehydration properties. Samples subjected to PEF and US treatment and dried by using a microwave-assisted method exhibited a significantly higher porosity of 2–4 folds in comparison to untreated material; this result was also confirmed by visual inspection of microtomography scans. Among tested methods, blanched samples had the most similar optical properties to untreated materials; however non-thermally treated bell peppers exhibited the highest saturation of the color. © 2022 by the authors. Licensee MDPI, Basel, Switzerland. 
650 0 4 |a antioxidant 
650 0 4 |a antioxidant activity 
650 0 4 |a Antioxidants 
650 0 4 |a blanching 
650 0 4 |a Capsicum 
650 0 4 |a carotenoid 
650 0 4 |a carotenoids 
650 0 4 |a Carotenoids 
650 0 4 |a chemistry 
650 0 4 |a color 
650 0 4 |a desiccation 
650 0 4 |a Desiccation 
650 0 4 |a drying 
650 0 4 |a kinetics 
650 0 4 |a Kinetics 
650 0 4 |a microwave radiation 
650 0 4 |a Microwaves 
650 0 4 |a pepper 
650 0 4 |a polyphenols 
650 0 4 |a porosity 
650 0 4 |a procedures 
650 0 4 |a pulsed electric field 
650 0 4 |a sugars content 
650 0 4 |a ultrasound 
650 0 4 |a water 
650 0 4 |a Water 
700 1 |a Dadan, M.  |e author 
700 1 |a Kaveh, M.  |e author 
700 1 |a Nowacka, M.  |e author 
700 1 |a Rybak, K.  |e author 
700 1 |a Wiktor, A.  |e author 
700 1 |a Witrowa-Rajchert, D.  |e author 
773 |t Molecules