FTIR-ATR infrared spectroscopy for the detection of ochratoxin A in dried vine fruit.
A method of screening sultanas for ochratoxin A (OTA) contamination, using mid-infrared spectroscopy/Golden Gate single-reflection ATR (attenuated total reflection), is described. The main spectral characteristics of sultanas from different sources were identified in a preliminary acquisition and spectral analysis study. Principal component analysis (PCA) showed that samples of various origins had different spectral characteristics, especially in water content and the fingerprint region. A lack of reproducibility was observed in the spectra acquired on different days. However, spectral repeatability was greatly improved when water activity of the sample was set at 0.62. A calibration curve of OTA was constructed in the range 10-40 microg OTA kg(-1). Samples with OTA levels higher than 20 microg kg(-1) were separated from samples contaminated with a lower concentration (10 microg OTA kg(-1)) and from uncontaminated samples. The reported methodology is a reliable and simple technique for screening dried vine fruit for OTA.
Galvis-Sánchez
Andrea C
AC
Departamento de Química, Universidade de Aveiro, Campus Universitário de Santiago, Aveiro, Portugal. asanchez@dq.ua.pt
Barros
Antonio
A
Delgadillo
Ivonne
I
D002273:Carcinogens / Q000032:analysis; D003890:Desiccation; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination / Q000032:analysis*; D005638:Fruit / Q000737:chemistry*; D009793:Ochratoxins / Q000032:analysis*; D015203:Reproducibility of Results; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D027843:Vitis / Q000737:chemistry*
D002273:Carcinogens; D009793:Ochratoxins; C025589:ochratoxin A