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太赫兹时域光谱（terahertz time domain spectroscopy，简称THz-TDS）技术是基于飞秒激光技术的新型光谱测量技术，它通过物质在THz波段的吸收特征可有效分析物质的结构和成分等相关信息。针对食品安全检测需求，采用THz-TDS技术进行了典型食品添加剂和非法添加剂的THz波谱分析与鉴别研究，测量分析了常用食品防腐剂苯甲酸和山梨酸、食品营养增补剂L-丙氨酸、食品调味剂L-谷氨酸钠，以及常被非法应用于食品增色的工业原料苏丹红I号在室温氮气环境下的THz吸收谱和折射率谱。研究发现这五类物质在THz波段均存在明显吸收峰，并具有指纹特性，可实现有效鉴别。应用Gussian03W程序包，基于密度泛函理论理论进一步模拟了 L-丙氨酸分子的振动来源，并对其在 THz波段的吸收峰进行了分析指认，为检测鉴别实验的可行性和有效性提供了理论依据。论文研究获取了典型食品添加THz波谱，分析掌握了各添加剂的THz吸收与折射特性，为食品安全检测提供了一种新方法。“,”Terahertz time-domain spectroscopy (THz-TDS) is a new spectral technique based on femtosecond laser technology. Through the absorption features of substances in THz band, the structure and composition of substances and other related information can be effectively analyzed. The terahertz spectra of food preservatives benzoic acid and sorbic acid, food nutritional supplement L-alanine, Food flavoring agent L-Glutamic Acid Sodium and illegal food additive Sudan I were got by THz-TDS in the Nitrogen surroundings at room temperature in demands of food safety inspection and assurance. The experimental results show that the THz spectra of these five kinds of food additives have distinct characteristics in THz region, which can be used as the fingerprint spectra and distinguish food additives. Finally, Gussian03W and density functional theory was applied in this research. The vibration source of L-alanine was simulated, and then the absorption of THz spectra of it was analyzed. The study demonstrated the feasibility of time-domain terahertz spectroscopy for the identification of food additives and provided a new way for the food security administration.