Determination of Caffeine in Soft and Energy Drinks Available in Market by
using UV/Visible Spectrophotometer
Asma Khalid, Sohail Ahmad, Huma Raza, Madiha Batool, Rida Khan Lodhi, Qura Tul Ain and Faiza Naseer
*
Department of Chemistry, Government Post Graduate Islamia College for Women, Cooper Road, Lahore, Lahore College for Women University Lahore, Pakistan
*
Corresponding author: Naseer F, Department of Chemistry, Government Post Graduate Islamia College for Women, Cooper Road, Lahore, Lahore College for Women
University, Lahore, Pakistan, Tel: 92 305 9386217; E-mail: faiza.naseer@ymail.com
Received date: 20 Jul 2016; Accepted date: 27 Jul 2016; Published date: 03 Aug 2016
Copyright: © 2016 Khalid A, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
This experiment did to determine the pH, levels of caffeine concentration in five soft drinks and four energy drinks
available in local market of Pakistan. pH were measured by pH meter. Quantitative estimation of caffeine
concentration in drinks was performed by a simple and fast standard UV spectrophotometric method (Perkin Elmer
lambda 35 UV/Vis spectrometer) using carbon tetrachloride as the extracting solvent at 270 nm wavelengths. The
minimum caffeine level of soft drinks was observed in Brand-3(10.69 mg/serving), while Brand-5 showed the highest
caffeine content (42.17 mg/serving) showing a range from 10.6 to 42.17 mg/serving. The concentration of caffeine in
all energy drink samples are well below the maximum allowable limits set by the food regulatory bodies, except E2.
The E2 has greater calculated concentration then the labelled concentration. The minimum caffeine level of energy
drinks was observed in E4 (32.04 mg/L) while E2 showed highest caffeine level in energy drinks (101.705 mg/
serving) showing range from 32.04 mg/serving to 101.705 mg /serving . And the pH range of these soft drinks were
(2.29 to 3.02) and in energy drinks (2.85 to 3.28).
Keywords: Caffeine; UV spectrophotometer; Comparison of soſt and
energy drinks
Introduction
Caffeine is a most common ingredient of energy drinks. It is added
as a flavouring agent and to make the drinks addictive [1]. Caffeine is a
bitter in taste, white crystalline xanthine alkaloid that acts as a
psychoactive stimulant drug and a mild diuretic. Almost sixty plant
species are known to contain caffeine [2]. Common sources of caffeine
are the "bean" (seed) of the coffee plant; in the leaves of the tea bush;
and in kola nuts. Some other sources include yaupon holly leaves,
South American holly yerba mate leaves, seeds from Amazonian maple
guarana berries [3]. Columbia In 1819, the German chemist Friedrich
Ferdinand Runge first time isolated pure caffeine in laboratory [4]
Caffeine is one of the world’s most widely used drugs. Many
anthropologists believe people used caffeine start from Stone Age.
Caffeine was first extracted from coffee in 1821 [5]. Caffeine is a
naturally occurring substance found in the leaves, seeds or fruits of
over 63 plants species worldwide and is part of a group of compounds
known as methyl xanthine's. e most commonly known sources of
caffeine are coffee, cocoa beans, cola nuts and tea leave [6]. Caffeine is
a naturally occurring substance found in humans, caffeine is a central
nervous system (CNS) stimulant [7]. It has the effect of temporarily
warding off drowsiness and restoring alertness. Beverages containing
caffeine, such as coffee, tea, soſt drinks and energy drinks, enjoy great
popularity [8]. Caffeine is the world's most widely consumed
psychoactive substance. Adults receive nearly three quarters of their
daily caffeine from coffee. Children receive one half of their caffeine
from soſt drinks Energy drinks represent a fast-growing beverage
market.
Different energy drinks having different amount of caffeine and its
range is from 50-300 mg. Most people experience no behavioural
effects with less than 300 mg caffeine. Sleep is more sensitive and can
be disrupted by 200 mg caffeine [9]. e caffeine content in your
average cup of coffee is around 100 mg. Decaffeinated coffee isn't
actually caffeine-free, and can contain up to 12 mg of caffeine. Your
average cup of tea contains 85 mg of caffeine. A single can of
commercially available energy drink can have anywhere between 80
and 280 mg of caffeine depending on the can size. Green tea is close
behind with 60 mg of caffeine, followed by white tea with 55 mg. Slim-
fast chocolate drinks come in at 20 mg of caffeine in a single serving
[10]. Caffeine is metabolized in the liver into three primary
metabolites: Para xanthine (84%), eo bromine (12%), and
theophylline (4%) [11] Caffeine is metabolized in the liver by the
cytochrome P450 oxidase enzyme system (specifically, the 1A2
isoezyme) into three metabolic dimethyl xanthine's (Figure 1) which
each have their own effects on the body [12].
Figure 1: Caffeine and its metabolites.
Family Medicine & Medical Science
Research
Khalid et al., Fam Med Med Sci Res 2016, 5:4
DOI: 10.4172/2327-4972.1000206
Research Article Open Access
Fam Med Med Sci Res, an open access journal
ISSN:2327-4972
Volume 5 • Issue 4 • 1000206