Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice

The objective of the research was to develop a method to extend the shelf life of freshly extracted sugarcane juice. The work focused on understanding the properties of sugarcane juice as well as determining methods of preserving the colour. Polyphenoloxidase (PPO) from sugarcane juice was extrac...

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Main Author:	Hoque, Mohammad Shamsul
Format:	Thesis
Language:	English English
Published:	1998
Subjects:	Polyphenol oxidase. Sugarcane. Fruit juices.
Online Access:	http://psasir.upm.edu.my/id/eprint/11840/1/FSMB_1998_12_A.pdf
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id	my-upm-ir.11840
record_format	uketd_dc
spelling	my-upm-ir.118402012-07-02T08:39:05Z Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice 1998-05 Hoque, Mohammad Shamsul The objective of the research was to develop a method to extend the shelf life of freshly extracted sugarcane juice. The work focused on understanding the properties of sugarcane juice as well as determining methods of preserving the colour. Polyphenoloxidase (PPO) from sugarcane juice was extracted, partially purified and characterised. Results indicated that the temperature for optimum PPO enzyme activity was 30°C at pH 7.6. Heat inactivation studies showed that enzyme lost 50% activity by exposure to 80, 75, 70 and 65°C for 1 .2, 2.8, 3.6 and 7.8 min, respectively. The use of ascorbic acid (0.5mM concentration), erythorbic acid (0.5mM concentration) and sodium metabisulphite (0.5mM concentration) inhibited the browning reaction 80%, 74% and 92%, respectively.The effect of different blanching conditions on the quality of juice was also investigated. Sugacane was blanched at various temperatures and time intervals using both steam ( 100 °C) and hot water (75°C, 80 °C and 85 °C). After blanching the juice was analysed for chlorophyll content, colour, PPO activity and tannin content and sensory evaluated for colour and taste. Unpeeled sugarcane stems which were steam blanched for 13±1 min yield the highest quality juice. Polyphenol oxidase. Sugarcane. Fruit juices. 1998-05 Thesis http://psasir.upm.edu.my/id/eprint/11840/ http://psasir.upm.edu.my/id/eprint/11840/1/FSMB_1998_12_A.pdf application/pdf en public masters Universiti Putra Malaysia Polyphenol oxidase. Sugarcane. Fruit juices. Faculty of Food Science and Technology English
institution	Universiti Putra Malaysia
collection	PSAS Institutional Repository
language	English English
topic	Polyphenol oxidase. Sugarcane. Fruit juices.
spellingShingle	Polyphenol oxidase. Sugarcane. Fruit juices. Hoque, Mohammad Shamsul Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice
description	The objective of the research was to develop a method to extend the shelf life of freshly extracted sugarcane juice. The work focused on understanding the properties of sugarcane juice as well as determining methods of preserving the colour. Polyphenoloxidase (PPO) from sugarcane juice was extracted, partially purified and characterised. Results indicated that the temperature for optimum PPO enzyme activity was 30°C at pH 7.6. Heat inactivation studies showed that enzyme lost 50% activity by exposure to 80, 75, 70 and 65°C for 1 .2, 2.8, 3.6 and 7.8 min, respectively. The use of ascorbic acid (0.5mM concentration), erythorbic acid (0.5mM concentration) and sodium metabisulphite (0.5mM concentration) inhibited the browning reaction 80%, 74% and 92%, respectively.The effect of different blanching conditions on the quality of juice was also investigated. Sugacane was blanched at various temperatures and time intervals using both steam ( 100 °C) and hot water (75°C, 80 °C and 85 °C). After blanching the juice was analysed for chlorophyll content, colour, PPO activity and tannin content and sensory evaluated for colour and taste. Unpeeled sugarcane stems which were steam blanched for 13±1 min yield the highest quality juice.
format	Thesis
qualification_level	Master's degree
author	Hoque, Mohammad Shamsul
author_facet	Hoque, Mohammad Shamsul
author_sort	Hoque, Mohammad Shamsul
title	Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice
title_short	Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice
title_full	Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice
title_fullStr	Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice
title_full_unstemmed	Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice
title_sort	properties of polyphenoloxidase of sugarcane and development of methods to prevent discolouration of juice
granting_institution	Universiti Putra Malaysia
granting_department	Faculty of Food Science and Technology
publishDate	1998
url	http://psasir.upm.edu.my/id/eprint/11840/1/FSMB_1998_12_A.pdf
_version_	1747811271965671424

Properties Of Polyphenoloxidase Of Sugarcane And Development Of Methods To Prevent Discolouration Of Juice

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