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: Beverage -> alcoholic -> sake

Citations 6

"Flow Injection Fluorometric Quantification Of Succinate In Foodstuffs Based On The Use Of An Immobilized Enzyme Reactor"
Anal. Chim. Acta 2000 Volume 416, Issue 2 Pages 197-203
Tadayuki Tsukatani and Kiyoshi Matsumoto

Abstract: A method for the quantification of succinate by flow injection analysis was developed using an immobilized-enzyme reactor and a fluorescence detection. Succinate was quantified using a co-immobilized isocitrate lyase (ICL) and isocitrate dehydrogenase (ICDH) reactor. Succinate was converted to isocitrate by ICL in the presence of glyoxylate, and then the produced isocitrate was oxidized with NADP(+) by ICDH. The NADPH produced by the ICL-ICDH reactor was monitored fluorometrically at 455 nm (excitation at 340 nm). A linear relationship between sensor responses and concentration of succinate was obtained in the range of 5-200 µM. The relative standard deviation for 10 successive injections was 1.01% at the 200 µM level. This analytical method was applied to the quantification of succinate in shellfishes and Japanese sakes, and the results showed good agreement with those obtained using conventional method (F-kit method).
Succinate Fluorescence Immobilized enzyme Reactor Interferences Optimization Method comparison

"Potentiometric Determination Of Ethanol In Alcoholic Beverages Using A Flow Injection Analysis System Equipped With A Gas Diffusion Unit With A Microporous Poly(tetrafluoriethylene) Membrane"
Anal. Sci. 1990 Volume 6, Issue 4 Pages 541-546

Abstract: The method involves the oxidation with K2Cr2O7 of ethanol permeating through a porous membrane, the reduction of unconsumed Cr2O72- with Fe2+ in a flow injection system, and the determination of the Fe3+ produced with a redox electrode. A diagram is presented of the flow injection manifold equipped with a gas diffusion separation unit. Results agreed with those obtained by a specific gravity method and by GC. The method is useful for application to alcoholic beverages owing to its high selectivity, high throughput, low cost and simplicity of operation.
Ethanol Potentiometry GC Gas diffusion Microporous membrane Redox Selectivity Heated reaction

"Simple Method For The Determination Of Amino Acids In Japanese Sake By Using Copper(II) Ion-selective Electrode"
Bunseki Kagaku 1986 Volume 35, Issue 12 Pages 990-993
Ohtsuka, C.;Wada, H.;Asano, Y.;Nakagawa, G.

Abstract: The amino-acids were separated by use of a HPLC column (25 cm x 4.6 mm) of TSKgel ODS-120A (5 m) and a mobile phase (0.23 mL min-1) of aqueous 5% ethanol and the eluate was subjected to post-column reaction with a flowing solution (0.27 mL min-1) containing 10 M Cu(NO3)2, 0.05 M 3-(N-morpholino)propanesulphonate buffer (pH 7.0), 0.05 M ammonium acetate and 1% of KNO3. The change of Cu(II) activity produced by reaction with the eluting amino-acids was monitored with a DKK-7141 Cu(II)-selective electrode. Calibration graphs for 0.02 to 0.15 g L-1 of glutamic acid, proline, valine, methionine, leucine, isoleucine and phenylalanine were rectilinear, but serine, glycine and alanine formed a single peak.
Amino Acids Electrode

"Spectrophotometric Determination Of Ethanol Based On Coloration Of Tetrabromophenolphthalein Ethyl Ester In Water - Alcohol Mixed Solvent"
Bunseki Kagaku 1988 Volume 37, Issue 6 Pages 301-305
Hosoi, Y.;Motomizu, S.

Abstract: The method is based on the color change of protonated tetrabromophenolphthalein ethyl ester(I) in acidic solution containing Triton X-100 on addition of alcohols such as methanol, ethanol, propanol and butanol. The method was applied in flow injection spectrophotometric determination of ethanol in alcoholic beverages, e.g., sake and whisky, pre-treated with activated carbon. Sample solution (100 µL) was injected into a carrier stream of water (0.8 mL min-1) which was then mixed with reagent solution containing 20 µM-I, 0.02% of Triton X-100 and 0.08 M acetate buffer (pH 4.4) and passed through a reaction coil before detection at 590 nm. The sampling rate was 45 h-1 without sample pre-treatment.
Ethanol Spectrophotometry Surfactant Triton X

"Determination Of Ethanol In Alcoholic Beverages By Gas Diffusion/flow Injection Analysis"
Bunseki Kagaku 1988 Volume 37, Issue 10 Pages T105-T108
Imato, T.;Ohura, H.;Asano, Y.;Yamasaki, S.;Ishibashi, N.

Abstract: The method involved use of a gas diffusion unit (illustrated), equipped with a poly(substituted acetylene) - polysiloxane copolymer membrane. Sample solution (140 µL) was injected into a carrier water stream, which was passed through one compartment of the gas diffusion unit at 70°C. Ethanol(I) diffused across the membrane, where it was absorbed by a carrier stream of water. This stream was mixed successively with ones of K2Cr2O7 solution, at 70°C, and of Fe(II) solution, and Fe(III) formed was determined by measurement of peak potential. Peak height was rectilinearly related to I concentration. in the range 5 to 30%. In the determination of 16% of I, the coefficient of variation (n = 6) was 1.9%. Sugars, amino-acids and carboxylic acids did not interfere. The method was applied in the analysis of sake, shochu and whisky.
Ethanol Potentiometry Gas diffusion Heated reaction Interferences Silicone membrane

"Flow Injection Analysis Of Organic Acids And Amino Acids In Sake By Using PH-sensitive Glass Electrode And Acid Base Buffer Solution"
J. Flow Injection Anal. 1986 Volume 3, Issue 2 Pages 103-111
Toshihiko Imato, Chie Azemori, Yasukazu Asano and Nobuhiko Ishibashi

Abstract: To determine organic acids, the sample solution was injected into a stream of water, which was merged with a neutral H2PO4- - HPO42- buffer solution The pH change caused by acid - base reaction between the acid and HPO42- was detected with a flow-through pH electrode. Amino-acids were determined by injecting the sample into a stream of water, which was merged with formaldehyde to convert the analytes into stronger acids; the resulting solution was merged with alkaline phosphate buffer solution and the change in pH was monitored as before. Results correlated well with those of conventional neutralization titration.
Carboxylic acids Amino Acids Clinical analysis Electrode Potentiometry