Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots

Low temperature long time (LTLT) blanching (70C for 20 min) together with calcium treatment can be used to significantly improve the texture of rehydrated dried carrots when compared to high temperature short time (HTST) blanching (100C for 3 min). LTLT blanching allows pectin methyl esterase to dee...

Full description

Bibliographic Details
Main Authors: Mohamed, Suhaila, Hussein, Rosli
Format: Article
Published: Wiley 1994
Online Access:http://psasir.upm.edu.my/id/eprint/112262/
_version_ 1848865896449179648
author Mohamed, Suhaila
Hussein, Rosli
author_facet Mohamed, Suhaila
Hussein, Rosli
author_sort Mohamed, Suhaila
building UPM Institutional Repository
collection Online Access
description Low temperature long time (LTLT) blanching (70C for 20 min) together with calcium treatment can be used to significantly improve the texture of rehydrated dried carrots when compared to high temperature short time (HTST) blanching (100C for 3 min). LTLT blanching allows pectin methyl esterase to deesterify pectin which can then react with calcium to form salt bridges. 0.3% L-cysteine-HCl was found to be most effective in preventing ascorbic acid loss and obtaining a product with the highest rehydration ability, compared to pretreatments with 0.3% N-acetyl-L-cysteine and 0.1% sodium metabisulphite. On the other hand 0.1% sodium metabisulphite was most effective in preserving the carotenoids content of dried carrots. Ascorbic acid and rehydration ability were more adversely affected by long drying time than high drying temperature, while carotenoids were more sensitive to high drying temperature than drying time. Hence, 60C drying temperature was good for ascorbic acid and rehydration ability, while 40C drying temperature was good for carotenoid and color of dried carrots.
first_indexed 2025-11-15T14:11:59Z
format Article
id upm-112262
institution Universiti Putra Malaysia
institution_category Local University
last_indexed 2025-11-15T14:11:59Z
publishDate 1994
publisher Wiley
recordtype eprints
repository_type Digital Repository
spelling upm-1122622025-01-13T23:51:36Z http://psasir.upm.edu.my/id/eprint/112262/ Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots Mohamed, Suhaila Hussein, Rosli Low temperature long time (LTLT) blanching (70C for 20 min) together with calcium treatment can be used to significantly improve the texture of rehydrated dried carrots when compared to high temperature short time (HTST) blanching (100C for 3 min). LTLT blanching allows pectin methyl esterase to deesterify pectin which can then react with calcium to form salt bridges. 0.3% L-cysteine-HCl was found to be most effective in preventing ascorbic acid loss and obtaining a product with the highest rehydration ability, compared to pretreatments with 0.3% N-acetyl-L-cysteine and 0.1% sodium metabisulphite. On the other hand 0.1% sodium metabisulphite was most effective in preserving the carotenoids content of dried carrots. Ascorbic acid and rehydration ability were more adversely affected by long drying time than high drying temperature, while carotenoids were more sensitive to high drying temperature than drying time. Hence, 60C drying temperature was good for ascorbic acid and rehydration ability, while 40C drying temperature was good for carotenoid and color of dried carrots. Wiley 1994 Article PeerReviewed Mohamed, Suhaila and Hussein, Rosli (1994) Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots. Journal of Food Processing and Preservation, 18 (4). pp. 343-348. ISSN 0145-8892; eISSN: 1745-4549 https://onlinelibrary.wiley.com/doi/10.1111/j.1745-4549.1994.tb00257.x 10.1111/j.1745-4549.1994.tb00257.x
spellingShingle Mohamed, Suhaila
Hussein, Rosli
Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots
title Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots
title_full Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots
title_fullStr Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots
title_full_unstemmed Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots
title_short Effect of low temperature blanching, cysteine-HCI, N-acetyl-L-cysteine, Na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots
title_sort effect of low temperature blanching, cysteine-hci, n-acetyl-l-cysteine, na metabisulphite and drying temperatures on the firmness and nutrient content of dried carrots
url http://psasir.upm.edu.my/id/eprint/112262/
http://psasir.upm.edu.my/id/eprint/112262/
http://psasir.upm.edu.my/id/eprint/112262/