Determination of acetate

Determination of acetic acid, vinyl ester in food simulants... 

Gorcharova and Khomenko [127] have described a column chromatographic method for the determination of acetic, propionic, and butyric acids in seawater, and thin-layer chromatographic methods for determining lactic, aconitic, malonic, oxalic, tartaric, citric, and malic acids. The pH of the sample is adjusted to 8 - 9 with sodium hydroxide solution. It is then evaporated almost... 

It is easily forgotten that aspirin degrades to acetic as well as salicylic acid. And, indeed, any smell aspirin might have is due to acetic acid. However, the volatility of acetic acid does not make the determination of acetic acid a reliable tool to measure stability or degradation. 

Some of the earliest work on NIR of bioprocesses was performed on the nutrients and metabolites in a fermentation broth. A classic paper (if 1996 is antiquity) was written by Hall et al.30 on the determination of acetate, ammonia, biomass, and glycerol in E. coli fermentations. This early paper used NIR to simultaneously monitor all the above-mentioned parameters. The correlation coefficients were all better than 0.985 with variable SEPs acetate, 0.7 g/1 ammonia, 7 mM glycerol, 0.7 g/1 and biomass, 1.4 g/1. While later work with more modem equipment has attained better results, this remains as one of the first. The work was performed at line in a cuvette, but rapidly enough to be considered a process measurement. 

Determination of acetic acid and trifluoroacetic acid (TFA) as impurity in synthetic peptide... 

Hettiarachchi, K., and Ridge, S. (1998). Capillary electrophoretic determination of acetic acid and trifluoroacetic acid in synthetic peptide samples. /. Chromatogr. A 817, 153 — 161. 

It is probable that GLC determination of acetic acid, as distinguished from other volatile acids (propionic, lactic, etc.), will be used more often. A specific enzymatic procedure for acetate (35) reveals that only about two-thirds of the volatile acidity is acetic acid. However, the volatile acidity of commercial wines in modem wineries is usually well below the legal limits. 

Schultz, T.H. 1965a. Determination of acetyle in pectin. Determination of acetate ester content by alkaline hydrolysis followed by distillation and titration of the liberated acetic acid. In Methods in Carboydrate Chemistry, Vol. 5 (R.L. Whistler, ed.) pp. 187-189. Academic Press, New York. 

Test kit for the determination of acetic acid (R-Biopharm GmbH, Darmstadt, Germany)... 

The test kit for the determination of acetic acid released is used according to the manufacturer s protocol (see also below). Spectropho to metric determination of NADH concentration is performed at 340 nm in the milliliter scale, e. g., in an Ultrospec 3000 photometer, and on the microliter scale in a fluorimeter, e. g. FLUOstar. 

Acetic Acid. On-line measurement of acetic acid concentrations is required in fermentation processes. The microbial sensor for ethyl alcohol described above could be used for the determination of acetic acid(8). 

Gibson, L.T., Cooksey, B.G., Littlejohn, D. and Tennent, N.H. (1997b) A diffusion tube sampler for the determination of acetic acid and formic add vapours in ambient air. Analytica Chimica Acta, 341, 11-19. 

E. Chulik has assisted in the foregoing work by developing analytical means for quantitative determination of acetate salts as modifications of the method of D. Ceausescu (17). 

From 1964, a method deseribed by Winter (1960) using an autoanalyzer (Teehnieon, USA) system was evaluated. The method is based on determination of acetic acid... 

Determination of acetic acid, vinyl ester in food simulants Determination of acrylamide in food simulants Determination of 11-aminoundecanoic acid in food simulants Determination of 1,3-benzenedimethanamine in food simulants... 

The DA of chitin can be determined by different hydrolytic techniques including chitin hydrolysis followed by determination of acetic acid or amino sugars produced. These methods have no requirement for the sample to be soluble. 

Table 169. Reproducibility of the determination of acetic acid in a sample...

J. W. Hall et al., Near-Infrared Spectroscopic Determination of Acetate, Ammonia, Biomass, and Glycerol in an Industrial Escherichia coli Fermentation, Appl. Spectrosc., 50(1), 26 (1996). 

A carbonate-free NaOH solution was found to be 0.05118 M immediately after preparation. Exactly 1.000 L of this solution was exposed to air for some time and absorbed 0.1962 g CO2. Calculate the relative carbonate error that would arise in the determination of acetic acid with the contaminated solution if phenolphthalein were used as an indicator. 

A NaOH solution was 0.1019 M immediately after standardization. Exactly 500.0 mL of the reagent was left exposed to air for several days and absorbed 0.652 g of CO2. Calculate the relative carbonate error in the determination of acetic acid with this solution if the titrations were performed with phenolphthalein. 

Figure 10 Calibration data and hardcopies for determination of acetic acid in mustard by potentiometric titration...

Virtually all of the methods for determining acyl groups developed up to now are based on re-esterification of the initial compound with sulphuric acid, a mixture of methanol with hydrochloric or p-toluenesulphonic acid, or with a mixture of p-toluene-sulphonic acid and its methyl ester [165—170]. The esters formed in the reaction were determined by analysing an aliquot of the reaction solution or by blowing-off the reactor with a carrier gas. Alkaline hydrolysis with subsequent determination of acetic acid has also been used for identifying acyl groups [167]. 

Morie, G.P. A method for determination of acetic acid and higher ahphatic acids in cigarette smoke 24th Tobacco Chemists Research Conference, Program Booklet and Abstracts, Vol. 24, Paper No. 13, 1970, p. 9. 

Hall J W, McNeil B, Rollins M J, Draper I, Thompson B G, Macaloney G (1996). Near-infrared spectroscopic determination of acetate, ammonium, biomass and glycerol in an industrial Escherichia coli fermentation. Appl. Spectroscopy 50 102-108. 

Immobilized Trichosporon brassicae cells have been used for the ampero-metric determination of acetic acid. Some properties of Zygosaccharomyces lactis cells immobilized on a modified hydroxyalkyl methacrylate gel have been reported. ... 

DS/EN ISO 1597 1999 Plastics - Unplasticized cellulose acetate - Determination of acetic acid yield... 

Rapid Gas Chromatographic Determination of Acetate in Human Plasma and Hemodialysis Baths... 

Gas Chromatographic Determination of Acetate in Biological Material Z. Klin. Chem. Klin. Biochem. 6(4) 277-280 (1968) CA 69 57369f... 

A Gas Chromatographic Method for Determination of Acetate Levels in Body Fluids... 

Determination of Acetic Acid in Blood and Other Tissues by Vacuum Distillation and Gas-Liquid Chromatography... 

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