Research on the stability for monascus pigment produced by Monascus purpureus JR

Monascus pigment is a native and mixed pigments produced by Monascus sp..Because of its flavor,aromatic fragrance,and vivid red color,monascus pigment is frequently used as a flavoring food addiitive.The stability of monascus pigment from Monascus-fermented rice produced by Monascus purpureus JR was investigated in this paper.Firstly,the effects of the natural light,fluorescent light and UV light on the stability of monascus pigment were studied,respectively,and the results showed that: monascus pigment presented significant instability on the natural light,fluorescent light and UV light irradiation.Secondly,the effect of different pH on the stability of monascus pigment was conducted,and the results show that: monascus pigment was very sensitive to pH,which was more stable in the neutral condition.Under the alkaline environment(pH value 9~11),monascus pigment was more stable than the acidic environment(pH = 3~5).Finally,the effect of temperature on the stability of monascus pigment was done,and the results showed that: Monascus-fermented rice produced by Monascus purpureus JR was stable to temperature.After being dealed with 80 ℃ for 2 h,the monascus pigment was still up to(985.33±9.45)U/g,which was only 50 U/g lower than that under room temperature(1038±15.87)U/g.