Abstract:  The stability of red pigment from Nitraria tangutorun Bobr fruit was investigated in this paper.The results showed that the pH has obvious effects on the pigment stability.In the range of pH1～4 there is little effect,but the metallic ions such as Cu2+,Mg2+,Zn2+,Al3+,Ca2+ can strengthen the pigment colour.While Na+,K+ has little effect.However,Sn2+ and Fe3+ have severe undesirable effect,to have changed the red color into some other color.It was found that the pigment is highly soluble,resistant to light,heat and reductant;but poor in resistance against oxide.Sucrose and EDTA have faint effects on the stability of the red pigment;whereas sodium benzoate has effects on the stability of the red pigment.The results showed that the pigment is worth of exploiting and utilizng.It may be used as one of the resources of natural edible pigment.

Key words: Nitraria tangutorun Bobr, red pigment, stability