Pigment was extracted from pericarp of black rice variety Zixiangnuo. The effects of several factors, including pH, light, chemical reagents and foodstuff additives on the color, solubility and heat stability of the pigment were observed. The color ofthe pigment varied with different acid conditions. When the pH was below 3, a stronger absorption peak at 495nm was observed. If the pH was between 3 and 10, there was a platform in 400-495nm. No obvious absorption peak in visible light region was foundwhen pH was above 10. As the pH increased, the color of the pigment changed from deep red to light red until to yellowish-brown, e.g. pH 0-2, deep red; pH3-4, red; pH5-6, quite red; pH9-10, faint red; pHll, faint brown yellow; pH12, light brown yellow;pH13, yellowish brown; pH14, deep yellowish brown. The change of color was reversible.
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