Abstract:
Coffee is one of the most popular stimulant beverages in the world, as it is highly rich
source of an alkaloid component known as caffeine. On the other hand, people are using
an ease and simplified preparation of coffee known as instant coffee, it also called
soluble coffee, coffee crystals and coffee powder. This study aims to determine the level
of caffeine in instant coffee samples randomly collected from Addis Ababa markets of
Ethiopia by using UV-Vis spectrophotometer and high performance liquid
chromatography (HPLC) techniques. Using these calibration curves the content of
caffeine in the collected coffee samples; Nescafe, Abyssinia and Mac coffee determined
in mg/g were 28.80 ± 1.91, 22.33± 0.21, and 13.20 ± 0.66 respectively, while using
HPLC, caffeine content for those samples in mg/g were also 6.33 ±0.01, 3.99 ± 0.03, and
3.25 ± 0.12 in respective way. From the measured caffeine contents of each samples the
content claimed by the manufacturer and the other research work reported were
comparable with the analytical results obtained from HPLC method .From this work the
amount of caffeine was also explained in dry weight analyzed using UV-Vis method was
included in the range of 1.32 ± 0.07% - 3.92± 0.13%, and using HPLC was also in the
range of 0.32± 0.012% - 0.63± 0.001%; this included in the range of the values of
WHO and FAO stated. In general, the caffeine concentration (mg/g) in each coffee
samples analyzed was in the order of Nescafe > Abyssinia coffee > Mac coffee using
both UV-Vis and HPLC techniques.