利用二次谐波在体分析番茄中的番茄红素和β-胡萝卜素含量

摘要

番茄中含有番茄红素和β-胡萝卜素两种重要的营养成分.两种成分的主要拉曼光谱基团相同,利用基频很难在体将两种成分区分开.应用激发波长为514.5 nm的激发光恰好处在番茄红素和β-胡萝卜素主要吸收带的半高宽范围内,因此能够发生共振拉曼效应.利用共振拉曼光谱技术,通过在体测量番茄中的番茄红素和β-胡萝卜素C=C碳碳共轭双键伸缩振动的二次谐波,用软件获得每种成分光谱的积分强度而得到番茄红素和β-胡萝卜素的含量,为在体检测同种基团成分含量提供一种方法.%Lyeopene and fl-carotene are two important nutritional components in tomato. The main Raman spectrum group of ly-copene and β-carotene abundant in tomato is identical and difficult to be distinguished through fundamental frequency. With exci-tation wavelength of 514. 5 nm, the excited light was just present in the half width range of the main absorption bands of Lyco-pene and β-carotene, so the resonance Raman effect can occur. Based on resonance Raman spectra, by on-body measuring the second harmonic of stretching vibration of carbon-carbon conjugated double bond in lycopene and β-carotene, the content of lyco-pene and β-carotene can be obtained according to the integrated intensity of each component calculated by software. And this pro-vides a method for on-body determining the content of the components with the homologous group.