Ochratoxin A in dried vine fruit: method development and survey.
A method is described for the determination of concentrations of the mycotoxin ochratoxin A in dried vine fruits (currants, raisins and sultanas) using acidic methanolic extraction, immunoaffinity chromatography clean-up and HPLC determination. The limit of detection was estimated as 0.2 microgram/kg, and recoveries of 63-77% were achieved at 5 micrograms/kg. HPLC-mass spectrometric confirmation of the identity of ochratoxin was obtained. Ochratoxin A and aflatoxins were determined in 60 samples of retail dried vine fruits purchased in the United Kingdom. Ochratoxin A was found in excess of 0.2 microgram/kg in 19 of 20 currant, 17 of 20 sultana and 17 of 20 raisin samples examined, an overall incidence of 88%. The maximum level found was 53.6 micrograms/kg. No aflatoxin was found in any sample analysed, using a method with a detection limit of 0.2 microgram/kg for each of aflatoxin B1, B2, G1 and G2.
MacDonald
S
S
CSL Food Science Laboratory, Norwich Research Park, UK.
Wilson
P
P
Barnes
K
K
Damant
A
A
Massey
R
R
Mortby
E
E
Shepherd
M J
MJ
D000348:Aflatoxins / Q000032:analysis; D002273:Carcinogens / Q000032:analysis*; D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D005519:Food Preservation; D009183:Mycotoxins / Q000032:analysis*; D009793:Ochratoxins / Q000032:analysis*; D019685:Rosales / Q000737:chemistry*; D012680:Sensitivity and Specificity
D000348:Aflatoxins; D002273:Carcinogens; D009183:Mycotoxins; D009793:Ochratoxins; C025589:ochratoxin A