Rapid identification of gutter oil by detecting the capsaicin using surface enhanced Raman spectroscopy

Abstract

Accurate determination of the gutter oil represents a major food safety challenge. Here, we propose to use the surface enhanced Raman spectroscopy (SERS) with silver nanorod array substrates to detect the capsaicin, a marker of the gutter oil that is difficult to remove. The capsaicin has several characteristic SERS peaks at Δv = 807 cm−1, Δv = 1, 264 cm−1, and so forth, which correspond to the C39‐C37‐C43 stretching vibrational mode at the alkyl chain, the ring stretching vibrational mode, and so forth, confirmed by our density functional theory calculation. This SERS‐based method enabled the rapid and highly sensitive detection of the gutter oil with minimum pretreatment. The concentration dependent SERS investigation shows that the SERS intensity of these characteristic peaks has a linear relationship with the capsaicin concentration when 1 mg/L < C < 60 mg/L. By combining a liquid phase extraction method and the SERS detection strategy, the capsaicin concentration as low as 30 mg/L can be detected from inoculated corn oil samples.

Ag Nanorods-Based Surface-Enhanced Raman Scattering: Synthesis, Quantitative Analysis Strategies, and Applications

“…Advantages of SERS, such as high sensitivity and easy operation have made it a powerful and promising technique for chemical detections in the field of food safety, such as beverages, pesticides, dairy production, and oil and so forth (Chen et al, 2015; Hou et al, 2016; Han et al, 2017; Roy et al, 2017; Jiang et al, 2018; Tian et al, 2018; Yao et al, 2018). For example, AgNRs substrate was employed for the rapid identification of gutter oil through capsaicin detection based on SERS (Tian et al, 2018). Figure 9A shows SERS spectra of the corn oil, extract liquor from corn oil which contains capsaicin, and capsaicin.…”

“…(B) SERS spectra of the extract liquor from gutter oil samples. Reproduced with permission from Tian et al (2018). Copyright (2018) John Wiley and Sons.…”

Recent advances in linear and nonlinear Raman spectroscopy. Part XIII

“…The FA nanostructure was functionalized by a DNA aptamer and used as a Raman reporter to specifically bind to Hg 2+ ions . Tian and co‐workers described the rapid identification of gutter oil by detecting capsaicin using SERS with with silver nanorod array substrates . Wang et al described a "drop‐wipe‐test" SERS method for the rapid detection of pesticide residues in fruits.…”

Pyrolysis-Gas Chromatography/Mass Spectrometry Analysis of Oils from Different Sources

“…In addition to the conventional physical and chemical indicators, the current detection/analytical methods of waste oils include various chromatographic methods, spectroscopy, nuclear magnetic resonance, etc. [3][4][5]. However, due to the complicated sources of waste oil, the complex composition, different processing methods, and different refining degrees, there is no single specific indicator or standard to distinct waste oils from edible oils.…”