o e r rThe thermal decomposition of ferulic acid has been studied by thermal gravimetric analysis. The decomposition products were separated by gasliquid chromatography and identified by GLC retention time and infrared spectral comparison with authentic materials. Combined gas-liquid chromatography-mass spectrometry and thin-layer chromatography were used as supplementary tools in product analysis.Unsubstituted, 4-methyl-, 4-ethyl-, and 4-vinylguaiacols were identified as products from the decomposition of ferulic acid in air and nitrogen atmospheres. Vanillin, acetovanillone (4-hydroxy-3-methoxyacetophenone), and vanillic acid were formed only in the air atmosphere. A mechanism is proposed for a portion of the ferulic acid decomposition.ardwood smoke used to cure food products consists of a variety of compounds-carbonyls, acids,

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Nitrosopyrrolidine (NO‐Pyr) formation in bacon is primarily dependent on frying temperature and not time. Cooking methods affect the amount of NO‐Pyr formed: pan frying produces the highest level of NO‐Pyr with variable concentrations formed on baking, broiling and cooking in a “baconer.” Microwave oven treatment produced the lowest amount of NO‐Pyr. A model system study of the decarboxylation of nitrosoproline shows this precursor, which may be present in bacon, is maximally converted to NO‐Pyr at 185°C near the recommended temperature for frying.

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Triazines are a class of important pre-emergent weed herbicides. Some members of this class of herbicides exhibit carcinogenic and immunotoxicity properties, which make their use controversial in areas where animal feed crops are grown. It is therefore important to determine if triazine residues are transported to animal food products in order to ascertain the extent of human exposure. Most of the current herbicide residue extraction methods are time-consuming and solvent intensive. Supercritical fluid extraction (SFE) using CO 2 has been used as a alternative for other residue extraction methods as a replacement for hazardous organic solvents. In this study, 10 triazines were extracted from eggs fortified at 100 ppb using unmodified supercritical CO 2 at a pressure of 10000 psi and a temperature of 50 °C with off-line collection on a solid phase extraction cartridge containing Florisil. Atrazine recovery averaged 90.4% with an RSD of 3.3%. The other triazines were recovered at mean levels >73%. In a separate feeding study, atrazine and two of its dealkyl metabolites were detected in the egg. The results indicate that SFE is a viable technique for isolating triazine residues from eggs, requiring only 8 mL of solvent for each analysis.

The efficacy of supercritical fluid extraction (SFE) for the recovery of 16 common organochlorine pesticides (OCPs) from liquid whole eggs was investigated by employing supercritical carbon dioxide (SC-CO(2)) without the use of a solvent modifier to minimize interfering coextractives. The OCPs tested included aldrin; alpha-, beta-, delta-, and gamma-BHCs; p,p'-DDD, -DDE, and -DDT; dieldrin; endosulfans I, II, and sulfate; endrin; endrin aldehyde; heptachlor; and heptachlor epoxide. The SFE conditions were as follows: 10000 psi (680 bar), 40 degrees C, SC-CO(2) flow rate of 3.0 L/min with an extraction time of 40 min for a total of 120 L of CO(2). The OCPs were trapped off-line in an SPE cartridge containing Florisil and then eluted by an acetone/hexane mixture and analyzed by gas chromatography-electron capture detection (GC-ECD). Recovery studies were carried out on homogenized eggs fortified at the 0.05, 0.10, and 0.20 ppm levels. At the lowest level, 0.05 ppm, recoveries ranged from 81.8 to 108.3%, with CVs < 9.8%. All recoveries were significantly higher than those obtained by an AOAC/FDA solvent extraction method. Eggs containing incurred endosulfan I were also effectively extracted by SFE. This study suggests that the application of SFE for the extraction of OCPs from eggs will result in significant savings in analysis time and lower solvent use and disposal costs compared to conventional solvent extraction procedures.