紫番薯色素和紫洋葱色素的稳定性比较研究

Comparative Study on the Stability of Purple Sweet Potato Pigment and Purple Onion Pigment

文章研究了温度、pH值、金属离子、氧化剂和还原剂等对紫番薯色素和紫洋葱色素两种色素稳定性的影响。实验结果表明,紫番薯色素和紫洋葱色素的热稳定性好;紫洋葱色素在酸性环境下具有更好的稳定性,而紫番薯色素则在碱性环境下具有更好的稳定性;金属离子K+、Na+、Mg2+对两种色素的影响均不大,但Fe3+、Cu2+对色素的影响较大。紫番薯色素受氧化剂和还原剂的影响较大,而紫洋葱色素耐受氧化剂和还原剂的能力较强。总之,两种色素均具有较好的化学物理稳定性,具有良好的开发利用前景。

The effect of temperature, pH value, metal ion, oxidant and reductant on stability of nature pigment in purple sweet potato and purple onion was studied in this paper. The results showed that the pigment had good heating stability in both of purple sweet potato and onion. The stability of onion pigment was better than that of purple sweet potato in acid environment, while the reverse took place in alkaline condition. The K＋, Na＋, Mg2＋ had small effect on the two pigment, while Fe3＋, Cu2＋ showed significant effect on them. The onion pigment had better stability than purple sweet potato pigment in oxidant and reductant. The two pigment have a high potential to be used as natural food colorants.