A study was made on the extraction of chlorophylls with ethanol from the dry brown seaweed Konbu, Laminaria japonica, and coloring under illumination with fluorescent light was investigated to improve the greenish color of the seasoning extractive from Konbu.
The results obtained were as follows: (1) The chlorophylls in the brown seaweed were effectively extracted with two-times the weight of absolute ethanol relative to that of the crushed dry material. (2) There was a negative correlation between the average particle size of dry seaweed and the extractable amount of chlorophylls with ethanol. (3) When the chlorophylls in ethanol solution were illuminated under fluorescent light, a greenish color developed. This coloring is supposed to be caused by allomelization of chlorophyll molecules. (4) It is clear that when the chlorophyll extract treated by illumination is added to the seasoning extractive of Konbu, the greenish color can be enhanced.