Analysis of Different Branded Soft Drinks by Qualitative, Quantitative and Spectrometric Methods

Abstract

Ten brands of ready-to-drink beverages “soft-drinks” were analysed for pH, sucrose, phosphate, glucose, fructose, and caffeine contents in soft drinks by using standard biochemical procedures. The soft drinks included ‘coca-cola’ popularly referred to as “coke”, “pepsi”, “mirinda”, “fanta”, “sprite”, “mountain dew”, “7up”, “limca”, “maaza”. The result shows that the pH of the soft drinks ranged from 2.46 in pepsi to 3.72 in maaza. Most of the soft drinks have alcohol and aldehyde as the flavouring agents. The concentration of sugar was tested in different cold drinks by comparing the density of different sugar solutions, which are used as sweetener agents in soft drinks. Test of corrosiveness in soft drinks explain the effect of soft drinks on the tooth enamel by studying the effect of cold drinks on a tarnished penny or coin, soft drinks remove the tarnish from the penny; and the darker sodas tarnish off the penny faster than the lighter sodas. The amount of ascorbic acid and benzoic acid is determined by using the titrimetric method and when these acids are used they inhibit the growth of yeast in soft drinks. In the process, it was discerned that the amount of Benzoic acid was generally low in fanta (29.75 mg/ounce) and highest in mountain dew (55.65 mg/ounce). Soft drinks also contain vitamin ‘C’; a low amount of vitamin ‘C’ is present in limca and the soft drinks having the highest content of vitamin C are coca cola and pepsi. The caffeine content in soft drinks was also analysed by UV spectroscopy. Only pepsi, cola, mountain dew and thums up contain caffeine. In other samples, the presence of caffeine or absorbance under the UV spectrometer was not detected.