Departamento de Física, Universidade Estadual de Maringá, Av. Colombo, 5790 Maringá, PR - 87020-900, Brazil.
Talanta. 2010 Apr 15;81(1-2):202-7. doi: 10.1016/j.talanta.2009.11.058. Epub 2009 Nov 30.
Photoacoustic spectroscopy (PAS) was applied as a method to quantify dyed food samples, and was compared with First Derivative Spectrophotometry (FDS). The dyes Brilliant Blue (B), Sunset Yellow (S) and Tartrazine (T), which are common food additives, were employed for the comparisons. Polyester-type Polyurethane (PU) foam was used for extraction of the dyes from a solution containing the food matrix. For the spectrophotometric determinations, the adsorbed dyes were recovered by using dimethylformamide. The PAS measurements were carried out directly on the PU foam. The PAS method showed greater sensitivity, with detection limits of 0.028 mg L(-1) and 0.086 mg L(-1) for S and T, respectively, in the S+T mixture, and of 0.012 mg L(-1) and 0.068 mg L(-1) for B and T, respectively, in the B+T mixture. The values of relative error obtained for all the dyes were small: approximately 0.3-3.6% for the spectrophotometer, and approximately 0.1-2.9% for the PAS method. The PAS technique can be applied to the determination of the selected dyes in commercial food products, with some advantages: it reduces the number of analysis steps, it is a "green" method with less chemical waste, a minimal sample amount is needed, and it is non-destructive.
光声光谱法 (PAS) 被应用于定量染色食品样品，并且与一阶导数光谱法 (FDS) 进行了比较。采用常见的食品添加剂苋菜红 (B)、日落黄 (S) 和柠檬黄 (T) 进行比较。聚酯型聚氨酯 (PU) 泡沫被用于从含有食品基质的溶液中提取染料。对于分光光度测定，通过使用二甲基甲酰胺回收吸附的染料。PAS 测量直接在 PU 泡沫上进行。PAS 方法具有更高的灵敏度，对于 S+T 混合物中的 S 和 T，检测限分别为 0.028 mg L(-1) 和 0.086 mg L(-1)，对于 B+T 混合物中的 B 和 T，检测限分别为 0.012 mg L(-1) 和 0.068 mg L(-1)。对于所有染料，获得的相对误差值都很小：对于分光光度计约为 0.3-3.6%，对于 PAS 方法约为 0.1-2.9%。PAS 技术可应用于商业食品产品中选定染料的测定，具有以下优点：减少了分析步骤的数量，是一种“绿色”方法，化学废物较少，需要的样品量较少，并且是非破坏性的。
