红曲霉JR所产红曲色素的稳定性研究

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

红曲色素是红曲霉在生长代谢过程中产生的多种天然色素的混合物。由于具有着色力强、口味自然等优点,红曲色素作为食用色素广泛运用于食品行业。文章对红曲霉JR固体发酵所得红曲米中的红曲色素的稳定性进行了初步研究。首先,考察了不同光照(自然光照、日光灯照射和紫外照射)对红曲色素稳定性的影响,结果表明:红曲色素在自然光、日光灯和紫外照射下均表现出显著的不稳定;考察了浸提过程不同pH对红曲色素稳定性的影响,结果表明:红曲色素对酸碱环境非常敏感,在中性条件下较为稳定,另外在一定的碱性环境下(pH值为9～11),红曲色素较酸性环境(pH值为3～5)更为稳定;最后考察了温度对红曲色素稳定性的影响,结果表明:红曲霉JR固体发酵所得红曲米中的红曲色素对温度较为稳定,当红曲米在80℃处理2h,红曲色素色阶仍可达(985.33±9.45)U/g,仅比室温条件下的红曲色素色阶(1038±15.87)U/g低50U/g左右。

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）, monaseus 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 monaseus 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.