M. Ihl et al., CORRELATION FOR PIGMENT CONTENT THROUGH COLOR DETERMINATION USING TRISTIMULUS VALUES IN A GREEN LEAFY VEGETABLE, SWISS-CHARD, Journal of the Science of Food and Agriculture, 66(4), 1994, pp. 527-531
The relationship between colour parameters of the chlorophylls and car
otenoids in the green leaves of Swiss chard was studied. Using the Hun
ter colour parameters (L(), a(*), b(*), chroma and hue angle) we foun
d a correlation coefficient r(2) = 0.9264 for the chlorophylls and r(2
) = 0.8595 for carotenoids. The chlorophyll a, b plus chlorophyllide a
, b extraction and the carotenoid extraction were carried out on the w
hole tissue using N,N-dimethylformamide as solvent. Using between 10 a
nd 50 mg tissue, the extractions with 3 ml solvent for 14-16 h at 4 de
grees C in darkness were quantitative for the chlorophylls; for the ca
rotenoids, the same procedure indicated a content approximating to the
level of provitamin A present in the leafy vegetable.