Effect of conventional and microwave cooking methods and time duration on the loss of vitamin C content in four green leafy vegetables

Chan, Wai Fang (2007) Effect of conventional and microwave cooking methods and time duration on the loss of vitamin C content in four green leafy vegetables. Universiti Malaysia Sabah. (Unpublished)

[img]
Preview
Text
ae0000001280.pdf

Download (3MB) | Preview

Abstract

Effect of cooking time (0.5, 1, 1.5, 2, 5 and 10 minutes) and cooking methods (boiling and microwave boiling) were studied for the percentage loss of vitamin C content in Chinese kale (Brassica alboglabra Bailey), water spinach (Ipomoea reptans Poir), dwarf white mustard (Brassica campestris sp. chinensis) and sweet shoot (Sauropus androgynus (L) Merr.). The vitamin C contents of the fresh vegetables and the percentage loss of vitamin C in cooked vegetables were subsequently determined by indophenol titration method. The results of the study revealed that all the studied vegetable species possess significant (p<0.05) difference in vitamin C content. The mean vitamin C content varied between 37.7 and 224.7 mg/ 100 g fresh weight with the highest content in sweet shoot and the lowest content in water spinach. The percentage loss of vitamin C content varied between 39.4% and 100% in Chinese kale, water spinach, dwarf white mustard and sweet shoot that were boiled for 0.5 to 10 min. While, loss in vitamin C for microwave boiling (0.5 to 10 min) ranged from 20.4% to 100% in four green leafy vegetables. The effect of different cooking time on vitamin C loss was significant (p<0.05). The % vitamin C loss for all the studied vegetables, due to boiling and microwave boiling, is in the order of 10 min > 5 min > 2 min > 1.5 min > 1 min> 0.5 min. The effect of the cooking methods on vitamin C loss was also significant (p<0.05), in which boiled leaves were found to loose more vitamin C than microwave-boiled leaves. In view of this it could be concluded that boiling and microwave boiling of vegetables though makes green leafy vegetables more palatable, however it reduces their vitamin C content drastically. Therefore, it is advised that microwave-boiled vegetables at shorter time may reduce the loss of vitamin C.

Item Type: Academic Exercise
Keyword: cooking time, cooking method, vitamin C, green leafy vegetables, microwave-boiled,
Subjects: T Technology > TX Home economics > TX1-1110 Home economics > TX341-641 Nutrition. Foods and food supply
Department: SCHOOL > School of Food Science and Nutrition
Depositing User: SITI AZIZAH BINTI IDRIS -
Date Deposited: 20 Aug 2013 16:52
Last Modified: 23 Oct 2017 15:35
URI: https://eprints.ums.edu.my/id/eprint/6790

Actions (login required)

View Item View Item