Organic Acids In Beer Research Articles

Determination of Organic Acids in Special Beers and Beer-Based Beverages Using Capillary Isotachophoresis

Organic acids in beer affect beer quality, including organoleptic properties and colloidal stability. A large proportion of the total organic acids in beer comes from the wort, while the rest is produced or transformed by yeast metabolism. Concentrations of five organic acids were determined in selected types of beer. Malic, succinic, citric, acetic and lactic acids were quantified. The concentration of acids varies according to the type of beer. The determination was made by the capillary isotachophoresis.

Dual-Opposite Injection Capillary Electrophoresis for Simultaneous Determination of Minerals and Aliphatic Organic Acids in Beer: Development, Validation, and Application

Dual-Opposite Injection Capillary Electrophoresis for Simultaneous Determination of Minerals and Aliphatic Organic Acids in Beer: Development, Validation, and Application

Determination of inorganic anions and organic acids in beer by replacement-ion chromatography with ultraviolet detection

Determination of inorganic anions and organic acids in beer by replacement-ion chromatography with ultraviolet detection

Changes in Organic Acids during Beer Fermentation

The profiles of seven kinds of organic acids (citric acid, malic acid, fumaric acid, succinic acid, lactic acid, formic acid, and acetic acid) of worts made from different proportions of rice adjuncts and corresponding beers were analyzed, and the changes in these organic acids during beer fermentation were studied. Results showed that rice proportions had a huge effect on the profiles of organic acids of wort and beer. The total content of these seven organic acids in the cooked rice mash was less than one-fifth of that in the all-malt wort when the extract was the same. The major organic acid in the cooked rice mash was acetic acid, which constituted about 40% of the total organic acids. The abundant organic acids in worts except for the cooked rice mash were citric acid, malic acid, lactic acid, and acetic acid, but the contents of fumaric acid and succinic acid were low. In comparison with the corresponding wort, the content of organic acids in beer obviously increased after fermentation, mainly owing to the excretion of succinic acid, acetic acid, and lactic acid. According to the change characteristics of organic acids during fermentation and their initial levels in wort, these seven organic acids were classified into three groups, namely, groups A, B, and C. Citric acid, malic acid, fumaric acid, and formic acid belonged to group A, for which excretion quantity was little during fermentation. Group B comprised lactic acid and acetic acid; the initial contents of these two organic acids were not low, and they were greatly formed during fermentation. Group C just had succinic acid, for which initial concentration in wort was low, but it was largely formed during fermentation.

Quantification of organic acids in beer by nuclear magnetic resonance (NMR)-based methods

The organic acids present in beer provide important information on the product's quality and history, determining organoleptic properties and being useful indicators of fermentation performance. NMR spectroscopy may be used for rapid quantification of organic acids in beer and different NMR-based methodologies are hereby compared for the six main acids found in beer (acetic, citric, lactic, malic, pyruvic and succinic). The use of partial least squares (PLS) regression enables faster quantification, compared to traditional integration methods, and the performance of PLS models built using different reference methods (capillary electrophoresis (CE), both with direct and indirect UV detection, and enzymatic essays) was investigated. The best multivariate models were obtained using CE/indirect detection and enzymatic essays as reference and their response was compared with NMR integration, either using an internal reference or an electrical reference signal (Electronic REference To access In vivo Concentrations, ERETIC). NMR integration results generally agree with those obtained by PLS, with some overestimation for malic and pyruvic acids, probably due to peak overlap and subsequent integral errors, and an apparent relative underestimation for citric acid. Overall, these results make the PLS-NMR method an interesting choice for organic acid quantification in beer.

Analysis of Non-Aromatic Organic Acids in Beer by CE and Direct Detection Mode with Diode Array Detection

A method for the analysis of the main non-aromatic organic acids in beer using capillary electrophoresis is presented. In this work, malic, citric, succinic, pyruvic, acetic and lactic acids are separated using a sodium hydrogen phosphate background electrolyte with direct detection mode with a diode array detector. The separation exhibits lower sensitivity than equivalent methods with indirect detection mode, however, the risk of co-migration with unknown compounds in beer matrixes is significantly reduced. This is due to (i) a higher efficiency (250,000–400,000 theoretical plates), (ii) a higher selectivity than any equivalent method using an indirect detection mode, and (iii) the possibility to monitor other wavelengths in parallel (260 nm for example) to check for possible co-migration with phenolic or benzoic acids. This was critical when working with beer samples as an unknown compound absorbing at 200 and 260 nm was detected in the neighbourhood of malic, citric and succinic acids. Such co-migration will not have been detected using single wavelength detection below 200 nm or indirect detection mode.

Organic Acids of Commercial Beers in China: A Chemometric Study

The concentration of six organic acids (acetic acid, lactic acid, pyruvic acid, malic acid, citric acid, and succinic acid) and pH were determined in 45 beer samples (23 from China and 22 from other countries) with the intention of associating the “moderate to very sour” character of Chinese local beers with particular acids. The content of acetic, lactic, and total organic acids in Chinese lagers was significantly higher, while citric acid was much lower, than that of foreign brands (P < 0.05). Using discriminant analysis, both stepwise and with all variables included, moderately strong classifications were obtained using the magnitude of the original gravity (low, medium, and high), the origin of the beer (Chinese or foreign), and the sourness intensity (slightly, moderately, and very sour) as the classification categories. These analyses supplied more information about organic acids in beer and its associated effect on the properties of lager beer.

Modeling the flavor thresholds of organic acids in beer as a function of their molecular properties

A mathematical model of the flavor thresholds of organic acids in beer as a function of their physical and chemical properties was constructed. Principal components analysis (PCA) was applied to 11 properties for 17 acids; this resulted in four significant principal components (PCs), which accounted for 93% of the variance in the property data. The PCs were dominated by the number of polar groups, the number of double bonds, molecular size, and solubility in non-polar solvents, respectively. PC scores indicating each acid's location along each of four scales were obtained. Literature data for acid flavor thresholds in beer were modeled as a function of the principal components using multiple linear regression and partial least squares (PLS) regression. The best-fit and best prediction equations were identical, with an R 2 of 0·905. ©

Simultaneous determination of carbohydrates and organic acids in beer and wine by ion chromatography

The simultaneous determination of mono-organic acids and carbohydrates by ion chromatography with both conductometric and pulsed amperometric detection is described. The carbohydrates, such as mannitol, arabinose, glucose, fructose, lactose, sucrose, raffinose, and maltose, as well as monoorganic acids including acetate, glycolate, formate, pyruvate, and fluoride are separated as anions by ion-exchange chromatography with 0.080 mol/L sodium hydroxide eluent at 1 mL/min within 12 min. Carbohydrates are determined by pulsed amperometric detection and mono-organic acids are determined by suppressed conductivity detection. The species in beverages are determined.

Determination of Organic Acids in Beer by Capillary Electrophoresis

The article includes details of a quantitative method for the analysis of malic, citric, succinic, pyruvic, acetic, and lactic acids in beer by capillary electrophoresis. The results of an experiment that tracked the levels of these 6 organic acids from cold wort to packaged beer are also presented

Determination of Organic Acids in Beer by Capillary Electrophoresis

A simple and rapid method for the determination of six prominent organic acids in beer by capillary electrophoresis was developed. Sample preparation involved dilution and pH adjustment. In less than 15 min, the levels of malic, citric, succinic, pyruvic, acetic, and lactic acids were determined. Separation was based on both size and charge. Reversed polarity and vacancy chromatography were utilized. The method was applied to track the levels of organic acids in a pilot brew from wort through to packaged beer.

Determination of Organic Acids in Beer After Extraction with an Anion-Exchange Resin

The organic acids in beer were recovered with an anion-exchange resin and then were converted to their methyl esters by treatment of the resin with boron trifluoride-methanol. More than 50 compound...

Determination of Organic Acids in Beer After Extraction with an Anion-Exchange Resin

Determination of Organic Acids in Beer After Extraction with an Anion-Exchange Resin

STUDIES ON YEAST DIFFERENTIATION USING ORGANIC ACID METABOLITES PART 1. DEVELOPMENT OF METHODOLOGY USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

The separation of organic acids on the column Aminex HPX-87H from Bio-Rad is described. The relationship between column temperature and retention time was studied for both sulphuric and phosphoric acid eluants and an analytical scheme using 0.2% (v/v) phosphoric acid was developed. While the procedure is designed for the commonly occurring non-volatile acid metabolites it was demonstrated that conditions could be established for the analysis of fatty acids to C10. Difficulties in the qualitative and quantitative analysis of organic acids in beer are discussed.

The Isolation and Identification of Organic Acids in Beer

(1968). The Isolation and Identification of Organic Acids in Beer. Proceedings. Annual meeting - American Society of Brewing Chemists: Vol. 26, Proceedings of the Annual Meeting 1968, pp. 113-119.