Microstructural changes in blanched, dehydrated, and rehydrated onion. Issue 12 (1st September 2022)

• Record Type: Journal Article
• Authors: Savitha, S.; Chakraborty, Snehasis; Thorat, Bhaskar N.
• Is Part Of: Drying technology. Volume 40:Issue 12(2022)
• Page Start: 2550
• Page End: 2567
• Publication Date: 2022-09-01
• Subjects: Dehydration -- rehydration -- intercellular space -- microstructure -- shrinkage; Drying -- Periodicals; Desiccation; 660.28426
• DOI: 10.1080/07373937.2022.2078347
• Languages: English
• ISSNs: 0737-3937

Abstract

Abstract: This study aims to explore the shrinkage of onion cells, single and multi-layer onion section, and expansion of intercellular pathways during dehydration. For macro and bulk-level studies, moisture analyzer and hot air convective dryer were used, respectively. Shrinkage, size retention, and color changes due to dehydration and rehydration of onion shreds were compared. At micro-level, CaCl2 and water blanched samples dehydrated at 70 °C, citric acid blanched samples dehydrated at 60 and 80 °C showed less shrinkage compared to unblanched samples. On rehydration, single layer section showed comparable cell size and intercellular space retention. Multi-layer section of CaCl2 blanched samples dehydrated at 70 °C retained better structure. At macro-level dehydration, shrinkage of CaCl2 blanched samples was the least. At bulk-level, all blanched samples shrank by 82–90%. Bulk level rehydration at 50 °C achieved better size retention. Blanching resulted a porous structure of onion shreds with an improved rehydration characteristics.