It had been recognized by many scientists in the early 1700s that the gas produced by brewery fermentation, combustion of wood and addition of acids to chalk/marble was one and the same. The most economical means of commercial production was by action of sulphuric acid on marble chippings or at the later date, on sodium bicarbonate. Crushed marble was cheap and readily available in a large quantity. However, the purity of the marble was critical to the quality of the CO2. Impurities would cause noticeable ‘off flavor’ in the finished drink. This forced manufacturers to introduce filters and scrubbers to remove taints. Bubbling the CO2 though olive oil was a commonly used method of removing organic taints. The purification of CO2 introduced complexity and hence cost to the production process.
Although more expensive than marble, sodium bicarbonate could be obtained in commercial quantities at consistently high purity and was preferred by some manufacturer. The product of action of sulphuric acid on marble is calcium sulphate, which is insoluble in water. Large quantities of the resulting sludge were difficult to dispose off, particularly when the United Kingdom municipal authorities introduced controls in 1890s. Problems of effluent emissions are not new. The liquefaction of CO2 by means of high pressure was reported by Michael Faraday in 1823 and the first practical manufacturing equipment was patented in Holland in 1877.The commercial manufacture and use of liquid CO2 for the carbonation of drinks began in Germany and in the United Sates of America in the 1889. The production of solid CO2 was discovered in 1835, and a patent for production and use of solid of CO2 was granted in 1897. The handling and transportation of solid block was much easier than for heavy metal cylinders containing liquid CO2. Though use of liquid or solid CO2 increased in the late nineteenth and early twentieth century, it was not until the 1950s that transportation of liquid CO2 by low pressure bulk rood tankers became commonplace.
Production of carbonated drinks was traditionally carried out by means of adding concentrated syrup to the bottle and then topping up with carbonated water. A considerable improvement in speed was achieved on 1937, when the Mojonnier Brothers Corporation of Chicago introduced a continuous blending/cooling/carbonating system.
Technology Development of Carbon Dioxide in Softdrinks
