Carbonation of beverages

Carbon dioxide has extensive commercial applications. Some important applications of this compound include carbonation of beverages as a fire extinguishing agent in the manufacture of carbonates as dry ice (solid CO2) for refrigeration as an aerosol propellant as a shielding gas for welding as... 

Membrane contactor offers potential solution in a wide range of gas/liquid and liquid/liquid applications gas adsorption and stripping, liquid/liquid extraction, dense gas extraction, fermentation and enzymatic transformation, pharmaceutical applications, protein extraction, wastewater treatment, chiral separations, semiconductor manufacturing, carbonation of beverages, metal ion extraction, protein extraction, and VOCs removal from waste gas [55]. 

One familiar application of Henry s law is in the carbonation of beverages. If the partial pressure of CO2 above a solution is increased, the amount dissolved in the solution increases proportionately. When the beverage can is opened, dissolved gas bubbles out of solution in response to the lower CO2 pressure outside. Henry s law is important in biology, where gases such as oxygen dissolve in blood and other bodily fluids, and in environmental chemistry, where volatile pollutants can move between bodies of water and the atmosphere. 

In addition to its role in natural processes, carbon dioxide has many commercial and industrial applications. One of the most important uses is in the carbonation of beverages. Although beers and sparkling wines contain carbon dioxide from natural sources (the fermentation of sugars by yeasts), nearly all carbonated beverages have their carbon dioxide added artificially. The carbon dioxide adds a zesty taste to the beverage and helps to preserve it. 

The laboratory will focus on the operational aspects of pH measurement. It is appropriate that we start this course with pH because this parameter is so fundamental to the physical-chemical phenomenon that occurs in aqueous solutions. The pH of a solution which contains a weak acid determines the degree of ionization of that weak acid. Of environmental importance is an understanding of the acidic properties of carbon dioxide. The extent to which gaseous CO2 dissolves in water and equilibrates is governed by the Henry law constant for CO2. We are all familiar with the carbonation of beverages. The equilibrium is... 

CO2 Carbon dioxide Carbonation of beverages, fire extinguishers, propellant in aerosols, dry ice... 

CO2 Carbon dioxide Fire extinguishers, dry ice, propellant in aerosols, carbonation of beverages... 

Carbonation can be measured ia terms of volumes of carbon dioxide dissolved ia one Hter of beverage at a standard temperature and pressure (0°C, 101.3 kPa = 1 atm). One Hter of carbon dioxide dissolved ia one Hter of beverage has a carbonation volume of one. 

Carbon dioxide gas is added to either the water used to prepare beverages or the symp and water mixture, depending on the type of manufactuting equipment. In both manufactuting processes, the carbon dioxide gas is iatroduced under pressure to the system. The carbonation of the beverage is dependent on the carbon dioxide pressure and the temperature of the mixture. 

Carbon dioxide used in carbonated beverages must be food-grade and must meet the Compressed Gas Association commodity specifications for carbon dioxide. In addition, carbon dioxide is tested for purity, taste, and odor before being used in the production of beverages. 

Our studies of the absorption, permeation, and extraction properties of containers produced from high nitrile barrier resins have demonstrated that they meet or surpass the basic criteria established for retention of taste and odor characteristics of carbonated soft drinks. Sensory tests, which can isolate and identify end results as well as integrate collective effects, have confirmed this judgement and have established the general compatibility of these containers with a variety of beverage products from a taste and odor standpoint. Furthermore, these materials have the excellent physical properties required for containers which will find wide use in food and beverage packaging. 

Non-carbonated RTD beverages have shown some considerable growth in recent years mainly because of the availability of aseptic packaging forms. Still drinks that rely on chemical preservation or hot-pack/in-pack pasteurisation suffer from a number of potential problems, including rapid flavour and colour deterioration. 

There are particular problems in the manufacture of non-carbonated RTD beverages that are not aseptically packed. These relate to microbial contamination. Products that have no carbon dioxide in their head space are particularly vulnerable to contamination by moulds and certain types of bacterial infection. For many years it was possible to control such potential contamination by the use of low levels of sulphur dioxide (50 ppm). Changes in European Preservative Regulations now make the use of this preservative in RTD formulations (but not dilutables) illegal unless it is carried over from a fruit component, when up to 20 ppm SO2 may be present. Even at this level, the gaseous preservative is rapidly lost and is quickly ineffective. 

The European Industrial Gases Association working with the Compressed Gases Association of America and the International Association of Beverage Technologists has prepared a specification for liquid carbon dioxide for use in foods and beverages. This is shown as Table 7.1. It is to this minimum standard that all carbon dioxide to be delivered to soft drinks and aerated mineral water bottles is manufactured. 

Giles, G.A. (ed.) (1999) Handbook of Beverage Packaging, Sheffield Academic Press, Sheffield. Mitchell, A.J. (ed.) (1990) Formulation and Production of Carbonated Soft Drinks, Blackie, Glasgow and London. 

First, with constraints on resources always an issue, there is usually a need to balance effectively the range of pesticide residues screened for and the number of samples analysed. The sampling plan for the NZTDS was devised to look closely at foods that were more likely to contain pesticide residues. For example, previous NZTDSs had indicated that carbonated cola beverage was unlikely to contain pesticide residues and so only two composite samples were analysed. By contrast, bread often contains residues of organophosphorus pesticides and so eight samples of each of three different types of bread were analysed. 

Further high quality wines are traditionally matured in oak cashs for several months. Maturation reactions are complex and like in spirit beverages, dissolution of wood components is of prime importance (8-9-10). Extracted wood components have secondary effect other than their direct flavor contribution. They appear to be necessary for correct maturation of the beverage. The effect of wood components on the maturation of beverages was clearly investigate in distilled alcoholic beverages only. The addition of oak extract to a model spirit solution reduced the extractability of ethyl esters with chain lengths of 10-20 carbons by the dichloromethane (9-10). The increase in solubility reflects a reduction in the activity of the ester in the aqueous ethanol solution, relative to the dichloromethane and indictes that an interaction between components of the wood extract and esters takes place. 

Carbon dioxide occurs in the atmosphere at 0.033%. It is produced by burning carbonaceous materials. It is used in the carbon-ation of beverages in fire extinguishers, in the manufacture of carbonates, as dry ice for refrigeration, and as a propellant for aerosols. 

Pasqualino M, Meneses EC. The carbon footprint and energy consumption of beverage packaging selection and disposal. J Food Eng 2011 103 (2011) 357-365. 

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