SIMULTANEOUS ESTIMATION OF CAFFEINE AND BENZOIC ACID IN SOFT DRINKS BY USING UV VISIBLE SPECTROSCOPY

SIMULTANEOUS ESTIMATION OF CAFFEINE AND BENZOIC ACID

IN SOFT DRINKS BY USING UV-VISIBLE SPECTROSCOPY

Vasubabu Padarthi*, Dr. K. N. Vidyadhar, Pudi Durgasyam, Yasarapu Manoj, Meka Jhansy Saranya and Mokara Laxmi Priya

Department of Pharmaceutical Analysis, V. J’S College of Pharmacy, Rajahmundry.

ABSTRACT

Five brands of soft drinks were analyzed for benzoic acid and caffeine

content by using simultaneous estimation method. The soft drink

includes Thums up, Limca, Coca cola, Sprite and Mountain dew. The

result shows that the pH of soft drinks ranges from 1.8 to 2.8. The

amount of benzoic acid and caffeine is determined by using

simultaneous estimation method. In this process, it was found that

amount of benzoic acid was low in Mountain dew. The caffeine

content in soft drinks was only found in Thums up, Coca cola and

Mountain dew and remaining other samples the presence of caffeine

absorbance under UV spectrophotometry are not detected.

KEYWORDS: Soft drinks, Benzoic acid, Caffeine, Simultaneous equation, UV Spectrophotometry.

INTRODUCTION

A soft drink is a drink that typically contains carbonated water, a sweetener and a natural or

artificial flavoring. The sweetener may be sugar, high-fructose corn syrup, fruit juice, sugar

substitutes (in the case of diet drinks) or some combination of these. Soft drinks may also

contain caffeine, colorings, preservatives and other ingredients.

Benzoic acid and its salts are used as a preservative, represented by the E-numbers E210,

E211, E212 and E213. Benzoic acid inhibits the growth of mould, yeast and some bacteria. It

is used either directly or as its sodium, potassium or calcium salt.

Volume 6, Issue 5, 749-755. Research Article ISSN 2277–7105

Article Received on 25 Feb. 2017,

Revised on 17 March 2017, Accepted on 06 April 2017

DOI: 10.20959/wjpr20175-8328

*Corresponding Author’

Vasubabu Padarthi

Department of

Pharmaceutical Analysis,

V. J’S College of

Caffeine which is chemically know as 1,3,7-Trimethylpurine-2,6-dione. Caffeine is a central nervous system (CNS) stimulant, having the effect of temporarily warding off drowsiness and

restoring alertness.

It increases calcium permeability in sarcoplasmic reticulum, inhibiting phosphodiesterase

promoting accumulation of cyclic AMP. The most prominent is that it reversibly blocks the

action of adenosine on its receptor and consequently prevents the onset of drowsiness

induced by adenosine. Caffeine also stimulates certain portions of the autonomic nervous

system.

BENZOIC ACID CAFFEINE

MATERIALS AND METHODS

The materials used are Hydrochloric acid (Molychem), Distilled water, Caffeine (Spectrum

% purity: 98.5 %), Benzoic acid (Merck% purity: 99.9%). Which are brought from the local

store of Siri scientific, Rajahmundry.

Preparation of solutions

Preparation of stock solution of benzoic acid

Weigh 0.010 gm of benzoic acid and transferred with DI water in a 500ml volumetric flask. It

may be difficult to get the solid to dissolve, so you may want to start by putting the solid in a

500ml Erlenmeyer flask (not a volumetric flask), adding about 400ml of water, and heating

on a heat plate. You will then have to make a quantitative transfer of the entire solution to the

volumetric flask. Once the solid is dissolved in the volumetric flask, fill the flask to the mark

with DI water.

Preparation of stock solution of caffeine

Prepare a stock solution of caffeine by dissolving 0.022gm caffeine (accurately weighed and

Sonicator to help dissolve the caffeine).Once the solid is dissolved fill the flask to the mark

with DI water.

Preparation of sample solutions: (Thums up, Limca, Sprite, Mountain dew, Coca cola) Pour exactly 20 ml of sample into a 125 ml Erlenmeyer flask, then Sonicator the sample for 5

minutes to remove dissolved CO2 .Using the micro pipette (with a new tip) take 2 ml of

sample in 50 ml volumetric flask and make up the volume with 0.01M Hcl.

RESULTS AND DISCUSSIONS THUMS UP

Fig no 1: Determination of caffeine and benzoic acid in Thums up.

λ for benzoic acid : 227 λ for caffeine : 272

Table no 1: λ max an absorbance values for caffeine and benzoic acid in Thums up. WAVELENGTH CAFFEINE BENZOIC

ACID THUMSUP A

1%

1cmCAFFEINE

A1%1cmBENZOIC

ACID

227 0.093 0.311 0.463 93 311

272 0.398 0.016 0.636 398 18

C1= a2λ2A1-a2λ1A2 b(a1λ1a2λ2-aλ1a1λ2)

C1=18 0.463-398 0.636 93 18-398 311

=8.334-253.128 1674-123778 = 0.002 C1= 20 mg

=93 0.636-311 0.463 93 18-398

=840.845 122104 = 0.0069; C2=69mg

SPRITE

Fig no 2: Determination of caffeine and benzoic acid in sprite.

Table no 2: λ max and absorbance value for caffeine and benzoic acid in sprite.

COCO-COLA

Fig no 3: Determination caffeine and benzoic acid in coco-cola. WAVELENGTH CAFFEINE BENZOIC

ACID SPRITE

A1%1cm

CAFFEINE

A1%1cmBENZOIC

ACID

227 0.093 0.311 0.421 93 311

Table no 3: λ max and absorbance values for caffeine and benzoic acid in coco cola.

MOUNTAIN DEW

Fig no 4: Determination of benzoic acid and caffeine in mountain dew.

Table no 4: λ max and absorbance values for caffeine and benzoic acid in mountain dew.

WAVELENGTH CAFFEINE BENZOIC ACID

MOUNTAIN DEW

A1%1cm

CAFFEINE

A1%1cm

BENZOIC ACID

227 0.093 0.311 0.625 93 311

272 0.398 0.018 0.346 398 18

LIMCA

Fig no: 5 Determination of benzoic acid and caffeine in Limca WAVELENGTH CAFFEINE BENZOIC

ACID COCACOLA

A1%1cm

CAFFEINE

A1%1cmBENZOIC

ACID

223 0.093 0.311 1.427 93 311

Table no 5: λ max and absorbance values for caffeine and benzoic acid in Limca.

Benzoic acid and Caffeine

Table no 6: Amount of benzoic acid and caffeine in soft drinks.

Company Benzoic acid concentration (mg/l) Caffeine concentration (mg/l) Company standards for benzoic acid(mg/l) Company standards for caffeine (mg/l)

[24 25 26 27 28]

Thumsup 20.0 69 70 52

Mountain dew 10.3 13.2 54 54

Limca 11.9 0.09 70 0

Coca-cola 19.8 31.2 46 46

Sprite 10.6 0.33 70 0

CONCLUSION

The analytical determination of benzoic acid and caffeine is not only important for quality

assurance purpose but also for consumer interest and protection. This work used is simple,

fast, and accurate UV-Visible spectroscopic method for the simultaneous determination of

benzoic acid and caffeine in five marketed samples of soft drinks Coca-cola, Thums up,

Sprite, Mountain dew, Limca. The results showed that the benzoic acid was found in all the

five soft drinks which are within the company standards. Whereas caffeine was found only in

Coca-cola, Thums up and Mountain dew which are also in company standards. So regular

checking of soft drinks should be done.

REFERENCES

1 H. Beckett, J. B. Stenlake. Simultaneous equations method: Practical pharmaceutical

chemistry. 4th edition part 2., New Delhi; CBS Publishers, 2007; 284-286.

2 Sandor Gorog. Multi component systems: Ultraviolet- visible spectrophotometry in

pharmaceutical analysis. Pharma Med press, 2011; 104-105.

3 Amos-Tautua, W. Bamidele Martin and E.R.E. Diepreye. Ultra-violet Spectrophotometric

Determination of Caffeine in Soft and Energy Drinks Available in Yenagoa, Nigeria.

Advance Journal of Food Science and Technology, 2014; 6(2): 155-158.

4 Doreen Amponsah. Determination of the amount of caffeine and benzoic acid in

selected soft drinks. International journal of scientific & engineering research, June 2014;

5: 1375.

WAVELENGTH CAFFEINE BENZOIC

ACID LIMCA

A1%1cm

CAFFEINE

A1%1cmBENZOIC

ACID

230 0.093 0.311 0.486 93 311

5 Zaifa Pan, Lili Wang, Weimin Mo, Wei Hu, Juan juan Zhang. Determination of

benzoic acid in soft drinks by gas chromatography with on-line pyrolytic methylation

technique. Analytica Chimica Acta, 2005; 545: 218–223.

6 M. A. Ford. The quantitative determination of benzoic acid in soft drinks by ion-exchange

chromatography. Analyst, 1966; 91: 15-22.

7 James K. Kusi, Samuel O. Levels of benzoic acid in soft drinks and fruit juices in Ghana.

IOSR Journal of Environmental Science, Toxicology and Food Technology

(IOSR-JESTFT) e-ISSN: 2319-2402, p- ISSN: 2319-2399, Dec 2014; 8: 36-39.

8 C.M. Lino , A. Pena .Occurrence of caffeine, saccharin, benzoic acid and sorbic acid in

soft drinks and nectars in Portugal and subsequent exposure assessment. Food Chemistry,

July 2010; 121: 503–508.

9 Qing-Chuan Chen, Jing Wang. Simultaneous determination of artificial sweeteners,

preservatives, caffeine, theobromine and theophylline in food and pharmaceutical

preparations by ion chromatography. Journal of Chromatography A, Dec 2001; 937: 1–2,

57–64.

10 Igelige Gerald1, David Ebuka Arthur1, Adebiyi Adedayo2. Paper Open Access

Determination of CaffeineIn Beverages. American Journal of Engineering Research

(AJER) e-ISSN : 2320-0847 p-ISSN ; 2320-0936, 2014; 3: 124-137.

11 Kathryn R. Williams, Alejandra Rodriguez Haralambides. Analysis of Soft Drinks: UV

Spectrophotometry, Liquid Chromatography and Capillary Electrophoresis. Journal of

chemical education, Feb 1966; 625: 15-22.

12 Pauline Maes, Yulia B. Monakhova, Thomas Kuballa, Helmut Reusch and Dirk W.

Lachenmeier. Qualitative and Quantitative Control of Carbonated Cola Beverages Using

1H NMR Spectroscopy. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY,

2012 Mar 21; 60(11): 2778-2784.

13 Nancy Karreman and Tom Zuzelski. Simultaneous Determination of Benzoic Acid and

Caffeine Concentrations by Single Wavelength. Isocratic High-Pressure Liquid

Chromatography. The Journal of experimental secondary sciences.

14 James k. kusi, Samuel o.Acquaah. Levels of benzoic acid in soft Drinks and Fruit Juices