University of North Florida
Browse the Citations

Contact Info

Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

View Stuart Chalk's profile on LinkedIn


Classification: Food -> black pepper

Citations 2

"Trapping System For Trace Organic Volatiles"
J. Chromatogr. A 1991 Volume 586, Issue 2 Pages 315-322
Tomás Jursík, Karel Stránský* and Karel Ubik

Abstract: A technique is described for the collection and concentration of volatile compounds produced by plants, animals and other materials which is a modification of the continuous-flow system based on absorption of volatiles in a low amount of solvent at low temp (cf. 'Proceedings of a Conference on Insect Chemistry and Ecology Tabor, Aug 12-18, 1990', Hrdy (Ed.), Academia, Prague, 1991, p.327). The trapping device (illustrated) works offline and the concentrated analytes are analyzed by GC (details given). The method was evaluated in the analysis of C8 to C22 alkanes and subsequently applied in the analysis of coffee beans, spruce bark, black pepper, beer and PVC floor covering. Chromatographs are presented. The advantages and disadvantages of the trapping device are tabulated.
Organics, volatiles GC C8 Apparatus

"Analysis Of United Kingdom-purchased Spices For Aflatoxins Using An Immunoaffinity Column Clean-up Procedure Followed By High Performance Liquid Chromatographic Analysis And Post-column Derivatization With Pyridinium Bromide Perbromide"
J. Chromatogr. A 1993 Volume 648, Issue 2 Pages 485-490
R. Colin Garner, Matthew M. Whattam, Patrick J. L. Taylor and Martin W. Stow

Abstract: Aflatoxins were extracted from powdered spices by homogenization with aqueous 80% methanol, the extracts were cleaned-up on Easi-Extract columns (Biocode Ltd.), extracted with chloroform and screened semi-quantitatively on silica-Florisil columns (Biocode Ltd.) on which aflatoxin is detected as a fluorescent band (details given). Samples containing >1 ppb of total aflatoxins were re-analyzed quantitatively by HPLC (with automated sample preparation and injection; details given) on a column (25 cm x 4.6 mm) of Spherisorb ODS2 (5 µm) with aqueous 40% acetonitrile/methanol (5:4) as mobile phase (0.75 ml/min) and post-column derivatization with aqueous pyridinium bromide perbromide (0.05 mg/ml; 0.3 ml/min) carried out in 30 cm of 0.25 mm tubing, and fluorimetric detection at 418 nm (excitation at 362 nm). Recoveries of aflatoxins B1, B2, G1 and G2 (added at 4 ppb to black pepper, chilli powder and ginger powder) are tabulated; the detection limit was ~0.06 ppb. The RSD for aflatoxins B1 and B2 in chilli powder were 4.7 and 2.2%, respectively. The method compares favourably with existing procedures.
Aflatoxins HPLC Fluorescence Post-column derivatization