Fermentation, alcoholic monitoring

In another very recent paper (Son et al., 2009b), the fermentative performances of yeast strains used for grape must fermentation were monitored by NMR and multivariate statistical methods. Characterization of the properties of wine yeasts is important because they affect wine quality. In this paper, the changes of metabolites in must during alcoholic... 

Tkac et al. [16] Ethanol Off-line monitoring of S. cerevisiae batch fermentation Alcohol oxidase (AOx) in Gluconobacter oxydans cells/covered with a cellulose acetate (CA) membrane Glassy carbon electrode/ +300mV vs. SCE Ferricyanide... 

The formation of hydrogen is accompanied with VFAs or solvent production during an anaerobic digestion process. Therefore, the distribution of VFA concentrations and their finctions is a usefiil indicator for monitoring hydrogen production. Fig. 3 shows the variations in alcohol and VFAs. Most of the VFAs were analyzed as acetate and butyrate, and most of the alcohols were analyzed as ethanol. The propionate concentration was below the analytical limit. It indicates that the anaerobic pathway in the reactor is not propionic-type fermentation but but5nrate-type fermentation. Clostridium butyricum is considered to be the dominant... 

Fayolle et al. used a remote system to monitor on-line fermentations.15 Both the substrates (glucose, fructose, lactose, and galactose) and the metabolites (ethanol and lactic acid) were monitored. The equations used were built with PLS. The reference method was HPLC. For the alcohol fermentation, glucose, fructose, and ethanol had SEPs (in g/1) of 3.5, 4.5, and 3.8, respectively. For the lactic acid fermentation, the SEPs for lactose, galactose, and lactic acid were 4.1, 1.4, and 2.0, respectively. 

A. Picard, I. Daniel, G. Montagnac and P. Oger, In situ monitoring by quantitative Raman spectroscopy of alcoholic fermentation by Saccharomyces cerevisiae under high pressure, Extremophiles, 11, 445 52 (2007). 

Chemical Analysis. It is suggested that a set procedure be established for running specific analyses according to a specific timetable. For example, a visual and taste inspection of all wines every two weeks (two months for wines in barrels), malic and lactic acid analyses at weekly intervals during the malo-lactic secondary fermentation, and S02 and color analyses of white wines at least every two weeks until the wine is bottled. Basic analyses to monitor are V.A., S02, alcohol, pH, and T.A. 

Quality control and analysis in the agro-food industry by the low resolution NMR was reviewed by D. N. Rutledge [83], in which NMR method is described as faster, more precise, simpler and cheaper technique than those traditionally used. For on-line monitoring of wine fermentation, EtOH and sugar alcohol beverage and fermenting musts were determined to a precision of 0.005-0.1% for EtOH and 4 8g/L for sugar by low resolution NMR [84]. 

D. Compagnone, M. Esti, M.C. Messia, E. Peluso and G. Palleschi, Development of a biosensor for monitoring of glycerol during alcoholic fermentation, Biosens. Bioelectron., 13(7-8) (1998) 875-880. 

M. Niculescu, T. Erichsen, V. Sukharev, Z. Kerenyi, E. Csoregi and W. Schuhmann, Quinohemoprotein alcohol dehydrogenase-based reagentless amperometric biosensor for ethanol monitoring during wine fermentation, Anal. Chim. Acta, 463(1) (2002) 39-51. 

On-line MIR ZnSe ATR analysis of microbial cultures has been used primarily for non-invasive monitoring of alcoholic or lactic fermentations. Alberti et al. [76] reported the use of a ZnSe cylindrical ATR crystal to monitor accurately substrate and product concentrations from a fed-batch fermentation of Saccharomyces cerevisiae. Picque et al. [77] also used a ZnSe ATR cell for monitoring fermentations and found that whereas NIR spectra obtained from alcoholic or lactic fermentation samples contained no peaks or zones whose absorbance varied significantly, both transmission and ATR MIR could be used successfully to measure products. Fayolle et al. [78] have employed MIR for online analysis of substrate, major metabolites and lactic acid bacteria in a fermentation process (using a germanium window flow-through cell), and... 

For bioprocess monitoring, the ET was employed in the assay of penicillin in fermentation broth, using /1-lactamase or penicillin acylase [28]. Also, ethanol generated in alcohol fermentation by yeast was monitored using alcohol oxidase. Other metabolites that were monitored during fermentations include lactate, glycerol, acetaldehyde, sucrose and glutamine [29]. 

Employing L-ascorbate oxidase, vitamin C (ascrobic acid) was determined in food samples between 0.05-0.6 mM [44]. In order to measure ethanol in beverages and blood samples, alcohol oxidase from Candida boidinii had been employed. Linearity was obtained between 0.01 and 1 mM. These measurements were also found to be useful in monitoring fermentation [47,48]. 

Rossignol, T., Dulau, L., Julien, A., and Blondin, B. 2003. Genome-wide monitoring of wine yeast gene expression during alcoholic fermentation. Yeast 20,1369-1385. 

These examples indicate the in situ applicability of enzyme electrodes however, numerous problems have still to be solved. At present, coupling of enzyme sensors for fermentation control in a bypass arrangement appears to be more favorable [412]. Following this concept, an invertase thermistor incorporating a sterilizable filter unit has been developed [413] for the monitoring of alcoholic fermentation by immobilized yeast cells. Another thermistor has been successfully used for on-line glucose measurement under real cultivation conditions of Cephalosporium acremonium [414]. Similar calorimetric devices are suitable for other fermentation processes and in environmental analysis. 

Ethanol is a common chemical material in the indnstry for alimental mannfactnring, cosmetic prodnction, and organic synthesis [107]. The ethanol sensors find application in various areas, such as drunken driving, monitoring of fermentation, and other processes in chemical indnstries [108,109], Ethanol is also one of the major canses of traffic accidents in the advanced conntries, so the laws and regnlations are made to improve the fitness of their people by changing the allowed alcohol level from time... 

Currently, the assay of carbohydrates is a very important criterion for the quality control of drinks and foodstuffs, especially in dietary products. Assay of carbohydrates is also very important in the fields of monitoring of food-labeling claims, analysis of sweeteners, bulking agents, and fat substitutes as well as for establishing authenticity and in the fermentation monitoring in the production of alcoholic beverages. 

A sensitive method for determining the C-14 content of ethanol is potentially attractive not only for age determination of certain alcoholic beverages, but also for environmental monitoring of this radionuclide. Ethanol is available in many areas surrounding sources of C-14 releases or can be obtained by rapid fermentation of various plant materials growing in these areas. 

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