A colour reaction for assessing rancidity in coconuts.

Krishnamurthy, M. N. and Chandrasekhara, N. (1974) A colour reaction for assessing rancidity in coconuts. Journal of Food Science and Technology, India, 11 (5). 238-239, 5 ref..

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Abstract

For storage studies, 3 samples each of freeze-dried and dehydrated coconut were equilibrated to 2% moisture. The samples were stored in screw cap bottles in an incubator at 37 degree C. A 100 mg of coconut was mixed with 10 ml of 8.8N HCl and the intensity of the pink colour measured by spectrophotometry at 520 nm. A decrease in the intensity of the colour was associated with the development of rancidity. Free fatty acids (FFA), peroxide values and carbonyls present were also used as rancidity indexes. Graphs of results are given. FFA increased from approx. 0.14 to 0.75% at the end of 9 wk and to 1.1% at the end of 12 wk. The concn. of saturated carbonyls dropped sharply initially and was negligible after 12 wk of storage. After 5 wk, rancidity was detected organoleptically; at this stage FFA and saturated carbonyls contents were between 0.45 and 0.5% and 4 and 5% respectively. Colour intensity with HCl decreased sharply during the first 5-7 wk of storage. There was no significant change in microbial population during 10 wk of storage. Data presented referred to freeze-dried coconut; similar results were obtained for dehydrated coconut.

Item Type:	Article
Uncontrolled Keywords:	RANCIDITY-; coconuts, rancidity detn. of; COCONUTS-; rancidity detn. of coconuts; SPECTROPHOTOMETRY-; STORAGE-; coconuts, rancidity of stored; ORGANOLEPTIC-EVALUATION; coconuts, rancidity evaluation of
Subjects:	600 Technology > 08 Food technology > 15 Flavour/Fragrance/Perfumes > 01 Sensory evaluation 600 Technology > 08 Food technology > 33 Nuts > 01 Coconut
Divisions:	Plantation Products Spices and Flavour Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	18 Mar 2010 09:09
Last Modified:	28 Sep 2018 10:53
URI:	http://ir.cftri.res.in/id/eprint/2441

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