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

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Classification: Food -> sausage

Citations 4

"Rapid Determination Of Zinc And Iron In Foods By Flow Injection Analysis With Flame Atomic Absorption Spectrophotometry And Slurry Nebulization"
Talanta 1990 Volume 37, Issue 7 Pages 711-718
João Carlos de Andrade*, Frederick C. Strong, III and Nadir J. Martin

Abstract: A rapid method of determining zinc and iron in food by flame atomic absorption spectrophotometry with slurry nebulization into an air-acetylene flame has been developed. A V-groove, clog-free Babington-type nebulizer, coupled to a single-line flow injection analysis (FIA) system, was employed to introduce the slurry into the spray chamber. Under the FIA conditions described, an injection frequency of 120/hr is possible, with negligible carry-over and memory effects. The calibration graphs were obtained by using various concentrations (up to 0.1 g/ml) of white bean homogenate as standards, rather than solutions. The method has been applied to various kinds of foods, including grains, vegetables, fruits and sausage. Homogenization of semi-prepared samples to form slurries took only 4 min. Relative deviations between results by the slurry and solution methods for both elements averaged 2-3%. Detection limits by the slurry method were 0.3 µg/ml Zn and 0.6 µg/ml Fe. A V-groove, Babington-type nebulizer, coupled to a single-line flow injection analysis system, was used to introduce sample slurry into the spray chamber for AAS determination. An injection frequency of 120 h-1 was possible, with negligible carry-over and memory effects. Calibration graphs were obtained by using 0.1 g mL-1 of white bean homogenate as standards. Homogenization of semi-prepared samples to form slurries took 4 min. Of air - acetylene and air - propane flames for the AAS, the former was preferred due to its rectilinear calibration graph. Relative deviations of results by slurry and solution methods for both Zn and Fe were 2 to 3%. Detection limits for the slurry method were 0.3 and 0.6 µg mL-1 of Zn and Fe, respectively. The method was applied to various foods, including grains, vegetables, fruits and sausage.
Iron Zinc Spectrophotometry Nebulizer Slurry

"A Sensitive Flow Injection Method For Determination Of Trace Amounts Of Nitrite"
Talanta 1998 Volume 45, Issue 6 Pages 1247-1253
M. F. Mousavi*, A. Jabbari and S. Nouroozi

Abstract: A new sensitive color reaction for nitrite determination is presented. In acidic medium, nitrite was reacted with safranine to form a diazonium salt which caused the reddish-orange dye color of the solution to change to blue. The carrier stream, into which the sample solution was injected, was doubly distilled water. The reagent solution stream, which contained safranine dye, hydrochloric acid and potassium chloride, was mixed with the carrier in a 3 m length of silicon tubing (bore 0.5 mm) maintained at 30°C in a thermostatic bath. The absorbance intensity was measured at 520 nm. The detection limit was 20 ng/mL and the RSD% of 20 injections of 1 µg/mL of nitrite was 0.65%. Anal. can be done at a rate of up to 30 h-1. Under the optimum conditions in the concentration. range of 30-4000 ng/mL of nitrite ion, a linear calibration graph was obtained (r = 0.9999). The method was applied successfully to the determination of nitrite in sausages.
Nitrite Spectrophotometry Heated reaction Optimization

"Use Of Focused Microwaves For Expeditive Shortening Of Sample Pre-treatment: Digestion And Reduction Procedures Prior To Selenium Speciation As Selenium(IV) Or Selenium(VI)"
Analyst 1995 Volume 120, Issue 8 Pages 2171-2174
W. Bryce, A. Izquierdo and M. D. Luque de Castro

Abstract: Methods for sample digestion and reduction of Se(VI) to Se(IV) using a focused microwave digestor, prior to Se determination, are described. The sample digestion method consisted of a three-step microwave digestion programme, using HNO3 and H2O2 (details given). The reduction of Se(VI) to Se(IV) was carried out online in a flow injection manifold in a 1 m Teflon reactor placed in the microwave chamber, using 6 M HCl as reductant. After reduction, the sample stream was diluted online before Se(IV) determination by flow injection cathodic stripping voltammetry (details given). The methods were applied to various sample types, viz., milk, sausage, kidney and water, and reduced the time required for both sample digestion and Se(VI) reduction.
Selenium(VI) Selenium(IV) Sample preparation Voltammetry Heated reaction Microwave Speciation

"Creatinine, Creatine And Protein In Cooked Meat Products"
Food Chem. 1998 Volume 63, Issue 2 Pages 187-190
Gloria del Campo*, Beatriz Gallego, Iñaki Berregi and J. Alfonso Casado

Abstract: The accuracy of the results obtained with a flow injection (FI) system for the simultaneous determination of creatinine and creatine in cooked meat products was evaluated in 30 samples by comparison with those obtained by reference methods. The FI method was then applied to 52 different samples (cooked ham, 14; frankfurters, 11; wieners, 9; chopped, 10; mortadella, 8) and the protein content was also determined From % creatinine of total creatine (creatine + 1.159 creatinine) an estimation of the heat treatment applied in the processing was made. Cooked ham, mortadella and chopped had the highest values, indicating that the cooking conditions were more severe of these products than those used in the sausages. The ratio of total creatine/protein permitted an estimation of muscular protein to be made. According to the mean value for this ratio, the products were ordered as: cooked ham 21.9 > chopped 17.7 > wieners 15.9 > mortadella 13.0 > frankfurters 12.3 mg total creatine per g of protein.
Creatine Creatinine Protein Method comparison