Abstract
This report analysed energy drinks and key components as well as investigates the rising popularity and effects of caffeinated energy drinks, particularly focusing on their impact on physical and mental health and label claim. This report included the energy drink industry generating significant revenue in the UK as well as in the global market. However, these beverages have become increasingly popular among adults and adolescents for instant energy. However, the report addressed the potential adverse effects of overconsumption, such as anxiety, insomnia, cardiovascular issues, and digestive discomfort.
The report also highlighted the global market trends and the reasons behind the increased consumption, particularly among younger populations, while stressing the importance of adhering to recommended consumption limits to avoid long-term health risks. The study focused on quantifying caffeine content in various energy drinks using HPLC and UV-visible spectrophotometry.
This study elaborately explained the lab experiments including the calibration curve and the caffeine quantification in energy drink samples. In addition, comparing observed concentrations with label claims which were comparable within 10% variation as well as calibration curves was established using caffeine standards, demonstrating excellent linearity with a slope of 59666.50465. Lastly, the HPLC method was highlighted for its effectiveness in separating and accurately quantifying caffeine.
Chapter 1
1.0. Introduction
According to the report of Ridder (2023), the energy drink industry in the UK belongs in the top ten positions and generates revenue of USD 4 billion. In addition, energy drinks have gained popularity among adults and teenagers due to their instant energy-providing features. This is a report of experiments on various caffeinated energy drinks from different companies. This report evaluates the effects of energy drinks and compares the label claim given by manufacturing company and lab results. The aim of the study is to analyse and review existing literature on caffeinated energy drinks. The purpose of the study is to gather data from lab experiments and analyse the results.
1.1. Energy Drinks
Energy drinks are becoming popular among adults and adolescents due to their exotic taste and instant energy. Furthermore, the non-alcoholic beverage industry introduced energy drinks that provide instant energy during performance (Kumstát and Vičar, 2020). Apart from that, energy drinks provide a rapid boost in concentration during performance as well as physical activity. The primary ingredient of the energy drink is caffeine as well available popular energy drinks contain 150 gm of caffeine per litre (Ambrose, 2024). In addition, energy drinks also contain added sugar or artificial sweeteners, vitamin B complex, amino acids and artificial flavours.
Figure 1: Energy Drink
(Source: Ambrose, 2024)
According to Redbull (2024), Red Bull energy drink contains 80 mg of caffeine which is less than any other popular caffeinated drinks like homemade coffee as well tea. Energy drink manufacturing companies also fortify vitamin B complexes including vitamin B12, B6, Pantothenic acids and Niacin. In addition, energy drinks contain sugar 27 gm as well as artificial sweeteners in the form of Sucralose for sugar-free drinks (Redbull, 2024). Furthermore, energy drinks contain the amino acid Taurine which is also present in various animal protein sources like fish and poultry. However, the presence of Taurine in energy drinks enhances mental and athletic performance. Energy drink also contains water, artificial colours and flavours that enhance the overall taste.
Figure 2: Sugar Content of Energy Drink
(Source: Clapp et al., 2019)
According to Statista (2023), the leading energy drink brands in the UK are Red Bull, Monster and Rockstar. Energy drinks are usually consumed for refreshment and instant energy instead of carbonated drinks. However, the high content of sugar in energy drinks impacts health badly and causes various lifestyle disorders.
Figure 3: Top Leading Brand of Energy Drinks in the UK
(Source: Statista, 2023)
1.2. Caffeine
Caffeine is a purine-based heterocyclic organic compound also known as 1,3,7-trimethyl xanthine (C8H10N4O2) (Reddy et al., 2024). Caffeine contains chemical stimulant properties due to its Alkaloid composition. In addition, these chemical stimulants are naturally occurring stimulants because of the methylxanthine chemical structure.
Figure 4: Chemical Structure of Caffeine
(Source: Reddy et al., 2024)
As per the research of Reddy et al. (2024), caffeine is found in different amounts naturally in coffee beans, cocoa beans and tea leaves as well as more or less another 60 various plant sources. For instance, different parts of plants like beans, leaves and fruits could contain caffeine with varying names including tea leaves containing theine. On the other hand, caffeine can be manufactured in the lab and is structurally similar to natural caffeine. In addition, popular dietary sources of caffeine are coffee, energy drinks, tea as well chocolates. As per the research of Ridder (2023), caffeine is very popular among adults as a form of coffee and in adolescents as a form of soft drinks or energy drinks.
1.3. Overview of Caffeine
Caffeine is a heterocyclic organic chemical compound that can occur naturally or synthetically. As per the report of Francescato et al. (2024), synthetic caffeine produced in the lab is structurally similar to natural caffeine and is used in the pharmaceuticals and beverages industry. Caffeine is an Alkaloid Methylxanthine derivative that provides instant stimulation properties in caffeinated products (Reddy et al., 2024). As per the view of Francescato et al. (2024), caffeine is consumed as a psychoactive substance worldwide and is also used instead of medicine in the treatment of headaches and respiratory depression. However, this psychoactive substance in caffeine increases alertness and enhances cognitive functions in humans. Caffeine has several positive impacts on health including enhanced metabolism and fat oxidation.
Figure 5: Source of caffeine
(Source: Rodak et al., 2021)
On the other hand, caffeinated energy drinks are manufactured with added sugars that negatively impact health (Clapp et al., 2019). In addition, caffeine is consumed as a dietary supplement, and it is used in medicine manufacturing. As per the report of Ridder (2023), an adult can consume caffeine 400 mg per day but expecting mothers and children can consume a limited amount of caffeine. Moreover, organic and synthetic caffeine contain similar structural properties and characteristics that open several paths of experiments.
1.4. Structure of caffeine
Figure 6: Molecular structure of caffeine
(Source: VectorStock, 2022)
According to Rodak et al. (2021), the molecular formula of caffeine is C8H10N4O2 which is basically a purine base. This molecular structure contains two types of ring such as a six-membered ring or pyrimidine and a five-membered ring. As per Figure 6, the molecular structure of caffeine has three methyl groups attached to a nitrogen atom (blue colour) and contains two carbonyl (C=O) (red colour) groups. This is a planer molecule with an amphiphilic nature which contains both hydrophilic and lipophilic characteristics (Rodak et al., 2021). The molecular structure contains both types of bonds single bonds and double bonds in the rings and methle groups are connecting with single bonds. However, this caffeine molecular structure can form hydrogen bonds with water molecules, contributing to its solubility.
| Physical Properties | Description |
| Texture | White, crystalline powder |
| Smell and Taste | Odourless and bitter |
| Molecular Weight | 194.19 g/mol |
| Melting Point | 235-238°C (455-460°F) |
| Boiling Point | 178°C (352°F) at 760 mmHg |
| pH | 6.9 |
| Density | 1.23 g/cm³ |
| Solubility | Highly soluble in boiling waterModerately soluble in ethanolSoluble in chloroform |
1.5. Properties of caffeine
- Physical Properties
Table 1: Physical Properties
(Source: Reddy et al., 2024)
- Chemical Properties
| Chemical Properties | Description |
| IUPAC Name | 1,3,7-trimethylxanthine |
| Weak Base | pKa = 10.4 (at 40°C) |
| UV Absorption | Maximum at 273 nm |
| Stability | Stable in normal temperature and resistant to heat |
Table 2: Chemical Properties
(Source: Reddy et al., 2024)
- Pharmacological Properties:
| Pharmacological Properties | Description |
| Stimulant | Affects the central nervous system |
| Lipophilicity | Able to cross the blood-brain barrier |
| Antagonist | Binds to adenosine receptors |
Table 3: Chemical Properties
(Source: Reddy et al., 2024)
1.6. Function of Caffeine
Caffeine is a heterocyclic organic chemical compound that has various functions in different aspects. According to Sharma et al. (2023), Caffeine acts as a stimulant that influences the CNS and creates an adenosine receptor blocking in the brain. Caffeine increases the secretion rate of dopamine also known as happy hormones as well as human neurotransmitters associated with pleasure and attention (Devi et al., 2023). Apart from that, this receptor-blocking mechanism reduces drowsiness and enhances alertness. On the other hand, Caffeine helps to boost metabolic rate and fat oxidation in the body that enhances weight reduction (Sharma et al., 2023). However, in the context of athletic performance caffeine boosts adrenaline levels that enhance performance levels as well as mood (Zheng, 2023). In addition, caffeine enhances focus and provides strengths to mental performance specifically during intense performance. Caffeine is used as an active component in different medicines such as in migraine, cold and flu treatments (Zheng, 2023). In addition, caffeine stimulant and soluble properties enhance function and chemical reactions with other chemicals and drugs.
Figure 7: Function of Caffeine in the Human Body
(Source: Guillán-Fresco et al., 2020 )
1.7. Uses of Caffeine
In recent years, Caffeine has gained popularity for its effectiveness in beverages and non-alcoholic drinks (Rodak et al., 2021). In addition, caffeine is a natural chemical compound but can be manufactured in the lab as well. This synthetic caffeine enhances its use in the pharmaceutical industry. Caffeine has various uses for consumption, industrial uses like make and cosmetic as well as pharmaceutical industry.
Beverages: Coffee, tea, soft drinks, and energy drinks contain caffeine as well as commonly consumed beverages which increase alertness and improve concentration (Ridder, 2023). In addition, non-alcoholic energy drinks contain caffeine but the ratio will differ as per the company. However, caffeinated beverages contain high levels of artificial or natural caffeine to boost energy and mental performance.
Sports: Caffeine enhances athlete’s strength and performance, and pre-workout supplements contain to improve focus and energy.
Pharmaceutical: Caffeine is a pain reliever due to its properties which effectively reduce headaches and migraines (Devi et al., 2023). As per the research of Korraa (2023), caffeine in the form of caffeine citrate is utilised in neonatal intensive care units to treat apnea of prematurity. In addition, this is a health condition where premature infants experience pauses in breathing (Korraa, 2023). Apart from that, Caffeine is used as a dietary supplement which helps to reduce body weight. On the other hand, cognitive functions like memory and reaction time are improved by caffeine.
1.8. Side Effects of Caffeine
Overconsumption of caffeine leads to various side effects in the human body and some of the effects have long-term impacts. On the other hand, overconsumption of caffeine depends on individual tolerance and body sensitivity (Luna, 2023). However, overconsumption of caffeine impacts as well as in specific health conditions like pregnancy, lactation and poor heart conditions caffeine consumption amount is restricted. According to Reddy et al. (2024), the daily recommendation of caffeine consumption for adults is 400 mg per day.
Figure 8: Side Effects of Caffeine
(Source: TheKnowledgeAcademy, 2023)
Impact on Nervous System: Caffeine has stimulant properties that impact the human central nervous system. As per Yamasaki (2023), a high amount of caffeine consumption causes anxiety and restlessness. As per the research of Grgic and Varovic (2024), 3 mg/kg or more of caffeine consumption can cause insomnia and jitters which are known as caffeine jitters. On the other hand, caffeine interrupts sleep quality and reduces sleep duration as well as dealing with the onset of sleep (Zhang et al., 2024). Furthermore, overconsumption of caffeine triggers panic attacks as well as anxiety disorders. Caffeine consumption in various types is very trendy in the world as well 175.6 million bags of coffee were consumed globally between the years 2021 to 2022 (Grgic and Varovic, 2024). On the other hand, If a daily consumer of caffeine suddenly withdraws it causes headaches, fatigue and less concentration.
Impact on Cardiovascular System: According to Marcinek et al. (2024), overconsumption of caffeine negatively impacts the cardiovascular system as well as causes a rapid heart rate and high blood pressure. In addition, excessive caffeine consumption with poor heart conditions increases the risk factors for arrhythmias.
Impact on the Digestive System: As per the research of Grgic and Varovic (2024), caffeine enhances the production of stomach acid that causes gastrointestinal discomfort and stomach ulcers. Furthermore, sometimes nausea and diarrhoea occur due to overconsumption of caffeine. In addition, overconsumption of caffeine causes dehydration if water intake is not adequate.
Impact on the Bone Density: High caffeine consumption increases risk factors for osteoporosis (Miao et al., 2024). In addition, Overconsumption of caffeine reduces calcium absorption which decreases bone density and increases the chances of osteoporosis.
1.9. Role of energy drinks in everyday life:
Energy drinks are non-essential products of our lives but modern approaches and trends include energy drinks in daily habits significantly in adults and adolescents. In addition, in the context of athletes, and professionals they often use it to enhance their performance level and boost concentration (Kumstát and Vičar, 2020). According to Ridder (2024), the non-alcoholic energy drink market continuously grows and achieves a total of 2.9 billion litres between 2023 and 2027.
Energy drinks consumed by adults and adolescents that used to enhance mental alertness and physical performance (Yamasaki, 2023). Adults to improve concentration and productivity consume caffeine. In addition, caffeine reduces sleep and delays sleep formation time which helps professionals in their jobs as well as increases alertness (Zhang et al., 2024). Furthermore, students use energy drinks to decrease fatigue and stay alert during long study hours. On the other hand, 29% of athletes use energy drinks to boost energy levels before performance (Taylor & Francis. 2024). However, energy drinks enhance performance levels and boost the concentration of students and adults.
1.10. Data on energy drinks intake worldwide
According to Statista (2024a), the global revenue of energy drinks was USD 193 billion in 2023 which can increase by USD 55 billion by 2027. As per the statistics, 52% of consumers consume energy drinks an average of 2 to 3 times a week (Elad, 2023).
In addition, the US energy drink market was top leading in 2023 and generated revenue of USD 19 billion (Statista, 2024a). Additionally, the Japanese energy drink market was an effective competitor generating USD 6 billion (Statista, 2024a). Furthermore, the UK energy drink market belongs in the top ten positions and generates revenue of USD 4 billion (Ridder, 2023). According to Statista (2024b), the United States is leading the rank with 29.19 litres of volume per capita in the energy drink market globally.
As per the report of Elad (2023), 25% of students in the United States of America consume energy drinks with alcoholic drinks. On the other hand, the United Kingdom contains 13.2 litres of volume per capita in the energy drink market globally (Statista, 2024b). In the last decades, the sale value of energy drinks has increased, and the sale value will increase by USD 159.1 billion in 2027 (Elad, 2023). Moreover, all statistics indicate the escalated market trends and the global market position.
1.11. Mechanism of energy production of energy drinks:
An energy drink is a compound chemical mixture that contains caffeine, sugar, and other fortified vitamins. This compound mixture expends energy and produces high calories in the body.
Caffeine Mechanism: Caffeine is the primary stimulant in energy drinks which blocks adenosine receptors in the brain. This blocking receptor reduces feelings of tiredness and increases alertness (Mihaiescu et al., 2024). In addition, this adrenaline can enhance physical and mental performance. Apart from that, the Adenosine and caffeine molecule structures are similar, and, in this context, caffeine replaces Adenosine and causes drowsiness. In addition, caffeine stimulates the release of neurotransmitters like dopamine that enhance mood and motivation. Furthermore, this mechanism increases alertness and temporarily boosts the physical performance of athletes.
Sugar Mechanism: Every energy drink contains sugar that enhances taste and provides energy. Sugar is a rapid source of glucose for the blood and quickly elevates blood sugar levels (Hazim et al., 2024). In addition, insulin secretion also increases the uptake of glucose in the cells rapidly providing energy (Hedrih and Staff, 2024). This lead to increased production of cortisol stress hormone that can increase alertness.
1.12. Beneficial and Adverse Effects of energy drinks
- Energy drinks contain caffeine that provides a quick boost in energy and alertness. However, this is beneficial for during periods of fatigue or highly energetic tasks.
- According to Costantino et al. (2023), energy drinks enhance cognitive functions including attention and memory and provide benefits to students and professionals during long work hours.
- Energy drinks improve physical performance in sports and exercise and seem to be beneficial for athletic performance.
- According to Jagim et al. (2023), energy drinks are an easily available instant energy source.
Adverse Effects:
Overconsumption of energy drinks leads to various side effects in the human body and some of the effects have long-term impacts.
- High-containing caffeine along with added sugar leads to increased heart rate and blood pressure and arrhythmias or other cardiovascular problems (Reddy et al., 2024).
- According to Zhang et al. (2024), energy drinks impact sleep quality and delay the onset of sleep leading to insomnia or disrupted sleep-wake cycles.
- According to Inchingolo et al. (2023), added sugar and acidic content enhance the occurrence of tooth decay and enamel erosion.
- Overconsumption of energy drinks enhances stomach upset, nausea, or diarrhoea which contribute to dehydration.
- Energy drinks impact the nervous system and cause anxiety and jitteriness in some individuals known as caffeine jitters (Grgic and Varovic, 2024).
1.13. How the body reacts when a human drinks energy drinks
Energy drinks contain caffeine and sugar both is reacted in the body rapidly and generates high energy. In addition, caffeine stimulates the central nervous system and blocks adenosine receptors that cause relaxation and sleepiness (Reddy et al., 2024). Additionally, the presence of caffeine increases urine production, which can lead to dehydration if fluids are not replenished (Costantino et al., 2023). On the other hand, high levels of sugar concentration in energy drinks provide instant energy. In addition, this high sugar content provides a quick spike in blood glucose levels (Inchingolo et al. (2023). Furthermore, high concentrations of caffeine in energy drinks lead to increased urination that contributes to dehydration and significantly water-imbalanced conditions. On the other hand, Taurine is fortified in energy drinks and helps the regulation of water and mineral salts in the blood (Santulli et al., 2023). energy drinks contain a few vitamins that help to provide various nutrients like vitamins and minerals. However, energy drinks contain caffeine that could be a cause of addiction and that leads to various types of health issues like type 2 Diabetes, weight gain and insomnia. in the view of the author Zhang et al. (2024), the stimulating effects of energy drinks disrupt sleep patterns and experience increased anxiety and restlessness due to the high caffeine content. However, caffeine has impacted heart conditions and blood pressure along with diabetes in the human body.
1.14. What hormone is released after intake of energy drinks that give energy to humans and feel energetic?
The main hormones that contribute to the feeling of increased energy and alertness after consuming a caffeinated energy drink are Adrenaline and cortisol (ud Din et al., 2024). Furthermore, caffeine stimulates the central nervous system, leading to the release of adrenaline from the adrenal glands. In addition, adrenaline is the “fight or flight” hormone that boosts blood flow to muscles and makes a person feel more alert and energetic (Pangaribuan and Batubara, 2023). Apart from that, cortisol is a stress hormone that is enhanced by caffeine consumption (ud Din et al., 2024). However, glucose availability in the blood is enhanced by cortisol which provides energy to the body in response to the stimulant. On the other hand, the consumption of energy drinks provides sugar and elevated blood glucose levels (Hazim et al., 2024). Apart from that, the pancreas releases insulin hormone that helps cells absorb glucose from the blood. Moreover, insulin manages blood sugar levels which provide a quick boost in energy (Hazim et al., 2024). Lastly, caffeine in the energy drink increases dopamine production in the brain which is a neurotransmitter associated with pleasure and reward (Gershman et al., 2024). Moreover, dopamine enhances feelings of motivation and pleasure contributing to the feeling of being enthusiastic.
1.15. Physical and mental effects of high-energy drink intake
Energy drinks temporary boost in energy and alertness but excessive consumption causes significant risks to both physical and mental health.
Physical Effects:
- Energy drinks enhance HR and BP due to their caffeine content and result into palpitations, chest pain, and arrhythmias (Marcinek et al. (2024). In addition, overconsumption of energy drinks with poor heart health increases the risk of cardiovascular events.
- High concentrations of caffeine in energy drinks lead to increased urination contribute to dehydration and significantly water-imbalanced conditions (Santulli et al., 2023).
- High consumption of energy drinks causes stomach upset, nausea, and vomiting due to high acidity and caffeine content.
- Caffeine stimulants interrupt sleep quality and reduce sleep duration as well as deal with the onset of sleep (Zhang et al., 2024).
- The added sugar in energy drinks silently gains weight and causes type 2-diabetes.
- According to Inchingolo et al. (2023), added sugar and acidic content enhance the occurrence of tooth decay and increase the risk of cavities.
- Excessive consumption has led to liver damage due to the high levels of caffeine and additives.
Mental Effects:
- According to Yamasaki (2023), caffeine in energy drinks causes anxiety and restlessness. In addition, high doses of caffeine exacerbate anxiety who already suffer from anxiety disorders.
- According to Grgic and Varovic (2024), overconsumption causes jitters which are known as caffeine jitters.
- Overconsumption of energy drinks impacts the nervous system and blocks adenosine receptors but when energy levels drop suddenly creating heightened aggression as well as irritability.
- Regular consumption of energy drinks leads to addiction to caffeine where the body requires caffeine to achieve the same effects as well as withdrawal symptoms like headaches and mood disturbances occur.
1.16. Why do young people consume these drinks more?
Energy drinks have gained popularity among adults and teenagers due to their instant energy-providing features. As per the statistics, consumers consume energy drinks an average of 2 to 3 times a week (Elad, 2023). As per the report of Elad (2023), students in the United States of America consume energy drinks with alcoholic drinks. However, energy drinks are launched with marketing propaganda where energy drinks boost energy levels and enhance alertness in a short period.
Furthermore, youth face hard schedules that require long hours of study. On the other hand, social media influences and marketing fliers enhance the popularity among peer groups that encourage consumption. Apart from that, energy drinks contain tasty flavours due to added sugars and flavours that are tastier than other traditional caffeinated beverages. The context of athletes, consume energy drinks to maintain physical performance in sports.
Moreover, nowadays energy drinks are widely available in convenience stores, supermarkets, and vending machines as well as online food delivery applications. These services are making the products easily accessible to everyone as well as the young generation. In addition, these energy drinks are very convenient no need to be prepared or cooked. Additionally, various brands are introducing different flavours whereas the excitement of exploring new taste that attracted more youth.
1.17. What CHANGES occur when a person consumes energy drinks by Age (minimum and maximum age of human)
Changes in the Body: Energy drinks conducts several physiological and psychological changes due to the ingredients like caffeine, sugar, and other additives.
- Stimulant ingredients enhance heart rate and blood pressure due to their caffeine content (Marcinek et al. (2024).
- High concentrations of caffeine in energy drinks lead to increased urination (Santulli et al., 2023).
- Caffeine stimulants interrupt sleep quality as well as deal with the onset of sleep (Zhang et al., 2024).
- The added sugar in energy drinks silently provides energy.
- Key ingredients of energy drink enhances strength and performance and improve focus and energy.
- Caffeine is providing instant stimulation and this psychoactive substance in caffeine increases alertness and enhances cognitive functions in humans (Reddy et al., 2024).
- As per the view of Francescato et al. (2024), energy drink is consumed as a psychoactive substance that used instead of medicine in the treatment of headaches and respiratory depression.
- Caffeine in energy drink has several positive impacts on health including enhanced metabolism and fat oxidation.
- Caffeine stimulates the CNS, results in increased alertness, reduced fatigue, and a temporary boost in energy levels.
- The blocking receptor of energy drink reduces feelings of tiredness and increases alertness (Mihaiescu et al., 2024). In addition, this adrenaline can enhance physical and mental performance.
- Caffeine in the energy drink increases dopamine production in the brain which is a neurotransmitter associated with pleasure and reward (Gershman et al., 2024).
- In the body, adrenaline the “fight or flight” hormone that boosts blood flow to muscles and makes a person feel more energetic (Pangaribuan and Batubara, 2023).
- Overconsumption of caffeine leads to anxiety, and panic attacks.
- High caffeine consumption increases risk factors for osteoporosis and reduces calcium absorption which decreases bone density and increases the chances of osteoporosis (Miao et al., 2024).
- The acidic nature and high levels of caffeine cause acid reflux and stomach ulcers.
Energy Drink Consumption Age Considerations:
Children and Adolescents (Under 18 Years): The consumption of energy drinks for children and adolescents is a new trend but impacted health in early age. In addition, the nervous and cardiovascular systems are developing in young age the high caffeine and sugar provide potential health risks. For instance, children could suffer from sleep disturbances, anxiety, and cardiovascular problems. Additionally, the bone health, tooth decay and cavities could occur due to added sugar and acidic content enhance (Inchingolo et al., 2023). Moreover, energy drink negatively impacted children health and strictly restricted it with strong regulatory body.
Young Adults (18-35 Years): Primary consumers of energy drinks are young adults and while consumption effect tolerated. In addition, overconsumption could lead to the adverse effects and most important to monitor their intake and be aware of the potential risks. In addition, the high-containing caffeine along with added sugar leads to increased heart rate and blood pressure and arrhythmias or other cardiovascular problems (Reddy et al., 2024). Apart from that, energy drinks impact sleep quality and delay the onset of sleep leading to insomnia or disrupted sleep-wake cycles.
Adults (35-50 Years): Adults in this age start to experience pronounced effects from energy drink consumption like hypertension or heart disease. In addition, the energy drinks enhance HR and BP due to their caffeine content and cause palpitations, chest pain, and arrhythmias in this age group (Marcinek et al. (2024).
Older Adults (50+ Years): the older adults and the associated risk with energy drink consumption increase equivalently significantly cardiovascular health. In addition, at this age overconsumption of energy drinks with poor heart health increases the risk of cardiovascular events.
1.18. Limit of energy drinks
- Energy drink generally not recommended for children and adolescents.
- Adults are mostly like energy drink and the maximum recommended daily intake of caffeine is 400 mg which is equivalent to about four cups of coffee (Reddy et al., 2024).
- Older adults should lower the intake or withdraw especially if they have any health conditions.
1.19. Summary
This chapter reviews all existing literature on energy drinks and caffeine as well as explores the growing popularity and effects of caffeinated energy drinks. In addition, this chapter analyses the global market of the energy drink industry in the UK. In addition, in this chapter detected ingredients of energy drinks and their chemical composition and chemical properties.
Chapter 2
2.0. Experimental Section
This chapter discusses the materials and methods involved with the analysis of caffeine detection from the energy drink. This chapter aims to explain all chemical material use and their measurement. In addition, this chapter’s main purpose is to describe effective methods of caffeine separation from complex solutions like energy drinks.
2.1. Instrumentation
2.1.1. High-Performance Liquid Chromatography (HPLC): According to El Deeb (2024), HPLC is an analytical technique used to separate chemical mixtures in the lab and identify and quantify components in the mixture. In addition, based on interactions with a stationary phase and a mobile phase, HPLC separates compounds (Santanatoglia et al., 2024). This analytical technique records the detector signal and processes the data to generate chromatograms and quantify results. In the context of caffeine analysis from energy drinks High-Performance Liquid Chromatography separates caffeine from other compounds in energy drinks. This analytical technique detects low concentrations of caffeine and provides accurate quantification of caffeine content. In addition, this method of analysis can analyse multiple samples with low manual involvement. Moreover, the High-Performance Liquid Chromatography analytical technique is ideal for caffeine analysis due to its accurate value and capability to handle complex mixtures like energy drinks.
2.1.2. UV-Visible Spectrophotometer:
As per the article of Kamble et al. (2024), the analytical technique UV-visible spectrophotometry is used to measure a sample’s absorption power. In addition, the absorption of light by molecules in the high-excited phase is the base of the UV-Vis spectrophotometry analytical technique. However, this method of analysis detects different chemical compounds that absorb light at different wavelengths (Ricchiuti et al., 2024). According to Kamble et al. (2024), the source of light is a 190-400 nm deuterium lamp for the UV region and a 400-1100 nm halogen lamp for the visible region. The detector of the UV-visible spectrophotometry method converts signals into absorbance values and spectra.
In this caffeine analysis from the energy drink context, UV-Vis spectrophotometry serves as a supportive technique for HPLC which generates accurate quantification of caffeine in complex energy drink matrices (Ricchiuti et al., 2024). The caffeine analysis from energy drinks sustains a 200-400 nm wavelength range and a wildly preferable wavelength range is 272 nm for caffeine (Hiremath et al., 2024). The UV-Vis spectrophotometry analytical technique scan speed is medium and utilises the mobile phase as blank.
On the other hand, the UV-Vis spectrophotometry method has limitations in analysing one product from multiple mixtures that create complications in finding caffeine in energy drinks (Ricchiuti et al., 2024). However, the similarity in wavelengths of the existing other products in the mixture can create confusion as well as provide inaccurate data. Apart from that, this analysing technique contains various limitations, but it can detect the purity and presence of caffeine as well as its standard in the sample.
2.1.3. Method for Extraction of Caffeine from Coffee Beans:
This is another method of caffeine extraction from coffee beans. According to Savić et al. (2024), a various sequence of chemical and physical processes are designed to separate caffeine from coffee beans. In addition, water, and organic solvents such as dichloromethane or chloroform are intensely involved with this method of extraction (Wale and Girma, 2023). Additionally, various processes are involved in the like alkalization and solvent evaporation to obtain crude caffeine. Lastly, purification steps extract caffeine in its higher purity. According to Wale and Girma (2023), this method is widely used in industrial experiments as well as in laboratory settings for the production of decaffeinated coffee. However, this method smooths the path of the HPLC method and its result accuracy.
2.2. Material
- Standard caffeine (Sigma Aldrich)
- Disodium hydrogen orthophosphate dihydrate (Sigma Aldrich)
- Methanol HPLC grade (Sigma Aldrich)
- Distilled water
- Phosphoric acid
- Energy drinks sample
- Redbull (coconut editions)
- Rockstar energy drinks
- Rubicon Raw energy
- Mountain Dew
- Nescafe gold coffee
Equipment:
- pH meter
- Volumetric flasks (10 mL, 50 mL, 100 mL, 1 L)
- Micropipettes and tips
2.3. Method: (Rosireddy, V. and Krishnan, M. (2024))
Standard solution preparation: Initially, prepare a standard solution with a reserve solution of caffeine 1 mg/mL by dissolving 50 mg of standard caffeine in 50 mL methanol.
Dilution: Prepare working standards by diluting the stock solution to concentrations of 0.01, 0.02, 0.03, 0.04, and 0.05 mg/mL using methanol.
- 0.1 mL in 10 mL
- 0.2 mL in 10 mL
- 0.3 mL in 20 mL
- 0.4 mL in 10 mL
- 0.5 mL in 10 mL
Mobile Phase: At first, dissolve 0.445 g of disodium hydrogen orthophosphate dihydrate in 1 L of distilled water to make a 0.01 M solution. Then, with the help of phosphoric acid adjust the pH to 7.0 and lastly filter it through a 0.45 μm membrane filter (Rosireddy, V. and Krishnan, M. (2024)).
Sample preparation: Initially, degas provided energy drink samples using the 10-minute ultrasonic bath method (Hagarová and Urík, 2024). As per the instruction, dilute samples appropriately with methanol which is determined based on the expected caffeine concentration. Lastly, the sample was filtered through a 0.45 μm membrane filter before injection
Extraction of Caffeine from Coffee Beans: Initially, prepare a sample solution with 1 gram of coffee beans and 200 mL of water in a beaker. After that, the extraction process began and the beaker on a magnetic stirrer and the mixture for a specified time of 20 minutes to allow the caffeine to dissolve in the water (Savić et al., 2024). Then, the filtration process was conducted where the solution was to remove the solid coffee particles and collect the filtered liquid (Wale, 2023). After that, add 20 mL of dichloromethane to the funnel and shake it gently to allow the dichloromethane to extract the caffeine from the water. After that, layers were separated then the dichloromethane layer which contains the caffeine as well as repeated this process with 20 mL of fresh dichloromethane. Lastly, all the collected dichloromethane layers were transferred to a rotary evaporator that extracted caffeine accurately.
UV Spectrophotometry Analysis Method:
The analytical technique UV-visible spectrophotometry is used to measure a sample’s absorption power in the high-excited phase (Kamble et al., 2024).
Process:
| Phase | Parameters |
| Wavelength scan range | 200-400 nm |
| Sampling interval | 0.5 nm |
| Scan speed | Medium |
Table 4: UV Spectrophotometry Analysis Method Parameters
(Source: Kamble et al., 2024)
- Utilising the mobile phase as blank.
- Scan standard caffeine solutions and energy drink samples.
- Analyse ranges to ensure caffeine peak
HPLC Analysis Method: According to El Deeb (2024), High-Performance Liquid Chromatography is an analytical technique used to separate caffeine from the mixture. In addition, based on interactions with a stationary phase and a mobile phase, HPLC separates compounds (Santanatoglia et al., 2024).
Process:
| Phase | Parameters |
| Column | C18 reverse-phase250 mm x 4.6 mm 5 μm particle size |
| Mobile phase | 80% methanol20% 0.01 M disodium hydrogen orthophosphate (pH 7.0) |
| Injection volume | 20 μL |
| Column temperature | 30°C |
| Detection wavelength | 272 nm |
| Run time | 10 min |
Table 5: HPLC Analysis Method Parameters
(Source: Santanatoglia et al., 2024)
- First, prepare a standard solution to create a calibration curve.
- After that, prepare energy drink samples by diluting with methanol.
- The calibration curve is essential for quantifying the caffeine in the energy drink samples.
- First, collect different fresh energy drink samples and put the drinks in the magnetic stirrer for degassed process to remove gas.
- Then, 10 mL of the energy drink sample was diluted with methanol to create a 1:5 dilution.
- Prepare a series of caffeine standard solutions in methanol at different concentrations 0.01 mg/mL, 0.02 mg/mL, 0.03 mg/mL, 0.04 mg/mL, and 0.05 mg/mL.
- Lastly, analyse the visible chromatograms to determine caffeine concentration in the solution.
2.4. Summary
As per the above scenario, these methods HPLC and UV spectrophotometry provide an exhaustive procedure for quantifying caffeine in energy drinks. However, both methods have different procedures and take different time ratios, but HPLC provides more accurate outcomes than UV spectrophotometry.
Chapter 3
3.0. Result and Discussion
3.1. Result
This chapter of the study explains all analysis reports and experiment outcomes that were achieved through practical lab experiments. In addition, this chapter aims to analyse the graphs and data achieved through the lab experiments. However, this experiment provides the caffeine quantity in the energy drink.
3.1.1. Calibration Curve:
The experimental data found in the lab constructs a calibration curve for caffeine standards. In addition, this analysis uses standard caffeine solutions to begin a calibration curve. This perfect calibration curve occurred due to perfect measurements of the sample as well as sample concentration.
Figure 9: Calibration Curve
(Source: made by author)
The linear analysis of this data yielded from the equation where y is the AUC and x is the concentration in mg/mL. In Figure 9, the perfect curve symbolised the accuracy in analysis and gradually increasing AUC with the concentration. The AUC value is documented in Table 6.
The equation is:
y = 59769x
As per Figure 9 the experimental quantitative data the calibration curve established excellent linearity with a slope of 59769.
Calibration Curve value:
| Concentration (mg/mL) | Average AUC |
| 0.01 | 615.695473 |
| 0.02 | 1236.149293 |
| 0.03 | 1722.000367 |
| 0.04 | 2374.525233 |
| 0.05 | 3024.187257 |
Table 6: Calibration Curve Value
(Source: made by author)
As per Table 6, five different concentrations range 0.01, 0.02, 0.03, 0.04 and 0.05 mg/mL were prepared and analyzed as well as represents the average area under the curve (AUC) for each concentration.
3.1.2. Caffeine Quantification in Energy Drink Samples
| Sample | Conc. Observed (mg/mL) | Label Claim (mg/mL) | Difference (%) |
| Coffee | 1785.93384 | N/A | N/A |
| Rubicon | 159.7909002 | 150 | +6.53% |
| Rockstar | 195.759264 | 200 | -2.12% |
| Red Bull | 81.1080396 | 75 | +8.14% |
| Mountain Dew | 63.57011396 | 76(Wikipedia Contributors (2019)) | +19.55% |
| Monster | 154.9574012 | 150 | +3.30% |
Table 7: Caffeine Quantification in Energy Drink Samples
(Source: made by author)
Table 7 demonstrates the outcome value of quantified caffeine concentrations in various energy drink samples. In addition, the analysis results represent a comparison of observed concentrations with the label claims. As per Table 7, the highest caffeine concentration was found in coffee which was 1785.933837 mg/mL. On the other hand, the lowest caffeine concentration was found in Mountain Dew which was 63.57011396 mg/mL.
Graph 1: HPLC concentration observed and label claim
(Source: made by author)
Graph 1 demonstrates the observed concentrations with the label claims of energy drinks. As per the HPLC concentration observed analysis coffee contains 1785.93mg/mL (for 1 gram of coffee beas) which is the highest concentration. In addition, Mountain Dew contains 63.570 mg/mL which is the lowest concentration of the analysis sample. In other energy drinks HPLC concentration observed is more or less average.
3.1.3 Obtained graphs and basic peak information:
Figure 10: HPLC chromatogram of Coffee
(Source: made by author)
Figure 10 demonstrates the HPLC analysis of coffee in wavelength 272 nm and gets four peaks 1 long and 3 shorts. The significant peak is situated at 2.241 minutes and accounts for 86.8413% of the total area. In this analysis report, 4 peaks were visible and contained one large peak along with three small peaks.
Peak segmentation:
| Ret Time (min) | Area (mAU*s) | Height (mAU) | Area (%) |
| 1.088 min | 87.14241 | 16.61483 | 4.7216 |
| 1.645 | 64.07310 | 8.01042 | 3.4716 |
| 1.732 | 91.64243 | 9.41669 | 4.9654 |
| 2.241 | 1602.75391 | 241.73425 | 86.8413 |
Table 8: Peak segmentation of HPLC chromatogram of Coffee
(Source: made by author)
The large peak is the caffein peak highlighted in Table 8, the retention time is 2.241 minutes, and the height of the peak is 241.73425 mAU. However, the caffeine peak area is 1602.75391 mAU*s which is 86.8413% of the total area.
Characteristics of Caffeine peak:
| Characteristics | Parameters |
| Retention time | 2.241 minutes |
| Peak are | 1602.75391 mAU*s |
| Peak height | 241.73425 mAU |
| Area percentage | 86.8413 of the total chromatogram area |
Table 9: Characteristics of Caffeine Peak
(Source: made by author)
Table 9, demonstrate the caffeine peak which shows the good separation of caffeine from synthetic caffeine with a symmetric peak shape.
Figure 11: HPLC chromatogram of Standard Caffeine
(Source: made by author)
Figure 11 demonstrates the HPLC analysis report of standard caffeine in 272nm wavelength. This analysis detected 2 peaks one large and one small peak. The second peak retention time is 2.259 min with 263.25797 mAU height. The area of the peak is 1722.86182 mAU*s which is 97.6843% of the total area. The total area is 1763.70447 mAU*s. The second peak is large and is considered a higher purity of caffeine which is the main component.
Characteristics of Caffeine peak:
| Characteristics | Parameters |
| Retention time | 2.259 minutes |
| Peak are | 1722.86182 mAU*s |
| Peak height | 263.25797 mAU |
| Area percentage | 97.6843 of the total chromatogram area |
Table 10: Characteristics of Caffeine Peak
(Source: made by author)
Table 10 and Figure 11, demonstrate the caffeine peak which shows the good separation of caffeine from coffee with a symmetric peak shape and established good column efficiency.
Figure 12: HPLC Chromatogram of Rubicon
(Source: made by author)
Figure 12 demonstrates the HPLC analysis report of the Rubicon energy drink in 272nm wavelength. This analysis detected 4 peaks one large and three small peaks.
Peak segmentation:
| Ret Time (min) | Area (mAU*s) | Height (mAU) | Area (%) |
| 1.102 | 178.78635 | 22.23563 | 14.7333 |
| 1.555 | 24.39023 | 2.48632 | 2.0099 |
| 1.807 | 52.17352 | 6.73373 | 4.2995 |
| 2.263 | 958.13452 | 155.49643 | 78.9573 |
Table 11: Peak segmentation of HPLC chromatogram of Rubicon energy drink
(Source: made by author)
In Table 11, The largest peak retention time is 2.263 min with 155.49643 mAU height. The area of the peak is 958.13452 mAU*s which is 78.9573% of the total area. The fourth peak is large and is considered a higher concentration of caffeine in the Rubicon energy drink.
Characteristics of Caffeine peak:
| Characteristics | Parameters |
| Retention time | 2.263 minutes |
| Peak are | 958.13452 mAU*s |
| Peak height | 155.49643 mAU |
| Area percentage | 78.9573 of the total chromatogram area |
Table 12: Characteristics of Rubicon Energy Drink Peak
(Source: made by author)
Table 12 demonstrates the caffeine peak which shows the good separation of caffeine from coffee with a symmetric peak shape on the complex solution of energy drink.
The HPLC analysis report of the Rockstar energy drink in 272nm wavelength. This analysis detected 4 peaks one large and three small peaks (Appendix 1).
Peak segmentation:
| Ret Time (min) | Area (mAU*s) | Height (mAU) | Area (%) |
| 1.124 | 131.41042 | 26.32733 | 9.4630 |
| 1.272 | 37.69490 | 8.52751 | 2.7144 |
| 1.822 | 46.3749 | 6.88696 | 3.3152 |
| 2.283 | 1173.53784 | 189.55229 | 84.5074 |
Table 13: Peak segmentation of HPLC chromatogram of Rockstar Energy Drink
(Source: made by author)
In Table 13, The fourth peak retention time is 2.283 min with 189.55229 mAU height. The area of the peak is 1173.53784 mAU*s which is 84.5074 % of the total area. The fourth peak is large and is considered a higher concentration of caffeine in the Rockstar energy drink.
Characteristics of Caffeine peak:
| Characteristics | Parameters |
| Retention time | 2.283 minutes |
| Peak are | 1173.53784 mAU*s |
| Peak height | 189.55229 mAU |
| Area percentage | 84.5074 of the total chromatogram area |
Table 14: Characteristics of Rockstar Energy DrinkPeak
(Source: made by author)
Table 14, demonstrates the caffeine peak which shows the good separation of caffeine from coffee with a symmetric peak shape on the complex solution of energy drink.
The HPLC analysis report of the RedBull energy drink in 272nm wavelength. This analysis detected 3 peaks one large and 2 small peaks (Appendix 2).
Peak segmentation:
| Ret Time (min) | Area (mAU*s) | Height (mAU) | Area (%) |
| 1.084 | 10.11989 | 1.75944 | 1.5547 |
| 1.810 | 55.84704 | 7.27796 | 8.5795 |
| 2.331 | 584.97150 | 101.62994 | 89.8659 |
Table 15: Peak segmentation of HPLC chromatogram of RedBull Energy Drink
(Source: made by author)
In Table 15, The third peak retention time is 2.331 min with 101.62994 mAU height. The area of the peak is 584.97150 mAU*s which is 89.8659 % of the total area. The third peak is large and is considered a higher concentration of caffeine in the RedBull energy drink.
Characteristics of Caffeine peak:
| Characteristics | Parameters |
| Retention time | 2.331 minutes |
| Peak are | 584.97150 mAU*s |
| Peak height | 101.62994 mAU |
| Area percentage | 89.8659 of the total chromatogram area |
Table 16: Characteristics of Rockstar Energy DrinkPeak
(Source: made by author)
Table 16 demonstrates the caffeine peak which shows the good separation of caffeine from coffee with a symmetric peak shape on the complex solution of energy drink. The HPLC analysis report of the Mountain Dew energy drink in 272nm wavelength (Appendix 3). This analysis detected 4 peaks whereas 2 large and 2 small peaks are visible.
Peak segmentation:
| Ret Time (min) | Area (mAU*s) | Height (mAU) | Area (%) |
| 1.108 | 601.84949 | 139.05128 | 42.4077 |
| 1.639 | 43.22115 | 3.23474 | 3.0455 |
| 1.834 | 11.00465 | 1.75385 | 0.7754 |
| 2.241 | 763.12323 | 127.50747 | 53.7714 |
Table 17: Peak segmentation of HPLC chromatogram of Mountain Dew Energy Drink
(Source: made by author)
In Table 17, The fourth peak retention time is 2.241 min with 127.50747 mAU height. The area of the peak is 763.12323 mAU*s which is 53.7714 % of the total area. The fourth peak is large and is considered a higher concentration of caffeine in the Mountain Dew energy drink.
The four distinct peaks were observed at retention times of 1.109, 1.597, 1.825, and 2.273 minutes. Moreover, based on the typical retention times for caffeine under similar HPLC conditions, the probable caffeine peak was 2.273 minutes peak (Appendix 4).
Peak segmentation:
| Ret Time (min) | Area (mAU*s) | Height (mAU) | Area (%) |
| 1.109 | 451.5005 | 111.41431 | 45.3910 |
| 1.597 | 32.02129 | 2.33026 | 3.2192 |
| 1.825 | 56.39380 | 8.04175 | 5.6695 |
| 2.273 | 454.77670 | 68.55531 | 45.7203 |
Table 18: Peak segmentation of HPLC chromatogram of Monster Energy Drink
(Source: made by author)
In Table 18, The fourth peak retention time is 2.273 min with 68.55531 mAU height. The first peak is large and is considered a higher concentration of caffeine in the Monster energy drink.
Characteristics of Caffeine peak:
| Characteristics | Parameters |
| Retention time | 20273 minutes |
| Peak are | 454.77670 mAU*s |
| Peak height | 68.555531 mAU |
| Area percentage | 45.7203% of the total chromatogram area |
Table 19: Characteristics of Caffeine Peak in Monster Energy Drink
(Source: made by author)
As per Table 19, the caffeine peak shows good separation from other components present in the Monster energy drink with a symmetric peak shape and established good column efficiency with a peak width of 0.1014 minutes. On the other hand, the large peak at 1.109 minutes indicates some colouring agent or impurities or other ingredients present in the samples.
3.1.3 UV Spectrophotometer
Analysis Conditions:
| Wavelength | 272.00 nm |
| Averaging time | 0.100 seconds |
| Spectral bandwidth | 2.00 nm |
| Detector | Compact UV-Vis |
Table 20: UV Spectrophotometer Analysis Conditions
(Source: made by author)
Table 20 demonstrates the analysis condition of the UV Spectrophotometer where the Wavelength was similar to HPLC analysis.
Figure 13: UV Spectrophotometer Wavelength scan
(Source: made by author)
Figure 13 demonstrates a wavelength scan of a UV-Vis spectrophotometer focusing on caffeine samples at two specific wavelengths 204.00 nm and 272.00 nm. In addition, the wavelength scan range was between 200.00 nm to 600.00 nm.
Wavelength Scan Data:
Sample 2: 272.00 nm wavelengths
| Sample (micro per litre) | Absorbance Values |
| 0.005 µL | 0.261 |
| 0.006 µL | 0.262 |
| 0.007 µL | 0.316 |
| 0.008 µL | 0.392 |
| 0.009 µL | 0.416 |
| 0.010 µL | 0.458 |
| 0.015 µL | 0.681 |
| 0.020 µL | 0.871 |
Table 21: UV Spectrophotometer Analysis
(Source: made by author)
Table 21 demonstrates the absorbance values show a gradual increase with the increase in concentration. In addition, the highest peak was created at 0.871 Abs for the highest concentration of 0.020 µL. This wavelength is considered as the peak absorbance of caffeine in the UV range. According to Table 23, the lowest peak was created at 0.261 Abs for the lowest concentration of 0.005 µL. In addition, the table displays the gradual enhancement of Absorbance Values with sample concentration.
3.2. Discussion of Results
3.2.1. Explanation of used chemicals
Methanol: In this quantitative analysis for preparing the caffeine standard solutions methanol plays a crucial role. This is an organic solvent which is commonly used in HPLC analysis due to its ability to dissolve an organic compound (Azmi et al., 2024). However, in this analysis, caffeine is an organic chemical compound and methanol easily dissolves in the solution of energy drinks (Najmi et al., 2024). Apart from that, the diluent methanol helps ensure the caffeine is fully solubilized which is crucial for data accuracy.
Mobile phase: As per the method, the mobile phase consisted of 80% methanol and 20% 0.01 M disodium hydrogen orthophosphate. The organic solvent methanol provides the organic modifier required for reversed-phase HPLC separation of caffeine from other compounds in the energy drink matrix. In this analysis, disodium hydrogen orthophosphate was an aqueous buffer which helps to maintain accurate pH in the solution (Azmi et al., 2024). However, the accuracy in pH balancing is important for the separation of caffeine in complex mixtures like energy drinks. Furthermore, in the mobile phase to adjust pH to 7.0 phosphoric acid is used which ensures the caffeine-neutral state (Najmi et al., 2024). This phosphoric acid improves the peak shape which provides an accurate outcome. On the other hand, the required polarity and solvating ability to elute caffeine from the C18 stationary phase is provided by this method-based mobile phase (Najmi et al., 2024). Apart from that, in the HPLC analysis of caffeine phosphate buffers are used for their UV detection compatibility.
3.2.2. Application of mobile phase
The mobile phase, in the caffeine detection context, consisted of 80% methanol and 20% 0.01 M disodium hydrogen orthophosphate buffer at pH 7.0. According to Alla et al., (2024), the mobile phase in High-Performance Liquid Chromatography is an essential component that directly impacts the separation of compounds. In this context, the mobile phase in the High-Performance Liquid Chromatography directly impacts caffeine solution. Apart from that, the mobile phase consists of a mixture of solvents and for caffeine analysis mobile phase contains a mixture of methanol and an aqueous buffer. In addition, the mobile phase serves as the carrier for the sample mixture and it moves through the column to separate based on its affinity for the stationary phase. In the case of caffeine, the pH of the mobile phase is controlled by the aqueous buffer disodium hydrogen orthophosphate. The application of the mobile phase along with the parameters ensures the successful separation and quantification of caffeine in HPLC analysis. Moreover, the mobile phase composition and pH, are essential to achieve high accuracy, and reproducibility in caffeine analysis.
3.2.3. UV Spectrophotometer Limitations:
In the context of caffeine analysis from the energy drink context, the UV-Vis spectrophotometer serves as a supportive technique for HPLC. This UV-Vis spectrophotometer generates accurate quantification of caffeine in complex energy drink matrices (Ricchiuti et al., 2024). On the other hand, this UV-Vis spectrophotometer has various limitations. The limitations occurred as an obstruction in the accuracy of outcome and peak formation. Apart from that, the UV-Vis spectrophotometer method has limitations in analyzing one specific product from multiple mixtures (Ricchiuti et al., 2024). However, this limitation creates complications in finding caffeine in energy drinks which was a complex mixture. After that, the similarity in wavelengths that occurred in the UV-Vis spectrophotometry created confusion in the analysis and provided inaccurate data. This inaccurate data decreases the potential importance of the data accuracy and outcome.
According to Santanatoglia et al. (2024), this UV-Vis spectrophotometer method is less complicated compared to HPLC. In addition, this process consumes less time and cost with less effective rapid results compared to HPLC. Hence, In this analysis context where energy drinks contain a complex mixture of various components UV-Vis spectrophotometry is utilised to detect the presence of caffeine. On the other hand, energy drinks contain sugars, vitamins, and additives that make a complex chemical solution. Furthermore, sugars, vitamins, and additives have the ability to UV light absorption at similar wavelengths as caffeine. Moreover, this interruption could lead to inaccuracies in the quantification of caffeine. Moreover, the chromatographic separation and specific UV detection at 272 nm qualify for more accurate quantification of caffeine.
3.2.4. HPLC Effectiveness:
High-Performance Liquid Chromatography is a highly effective method for analysing caffeine in complex mixtures like energy drinks. In addition, this method provides precision, accuracy, and sensitivity. As per the report of Santanatoglia et al. (2024), HPLC provides an excellent outcome in separating and detecting caffeine from complex components in the energy drink samples. Furthermore, HPLC offers higher accuracy in determining the caffeine content in the energy drink samples. However, this generates a calibration curve and quantifies caffeine based on peak area. Furthermore, HPLC offers separating and quantifying caffeine with high precision and ensures consistent outcomes (Marzouk et al., 2023).
Furthermore, this analysing method provides accuracy which is enhanced calibration curves and internal standards. On the other hand, HPLC’s selectivity conducted effective separation of caffeine from other components in a mixture, using a C18 reverse-phase column for optimal retention and separation. However, High-Performance Liquid Chromatography is highly sensitive in the detection of caffeine at very low concentrations with wavelengths of 272 nm. Apart from that, HPLC analyzes multiple compounds simultaneously with automation capabilities that make it appropriate for high-throughput analysis. Lastly, HPLC is utilised for industrial research for its accuracy and efficiency in quantifying caffeine in various products.
3.2.5 some important result discussion regarding energy drinks:
After finding the results and comparing with the label claim, there is a surprise element that mountain dew having unknown amount of caffeine in the bottle but there is not specific amount of caffeine declared in the packaging. As per author’s result , the amount of caffeine was found to be 63.57 mg per 500 ml of bottle. However, there should a amount of caffeine printed in the label as this drinks are consumed by the young childrens aging from 8 to 16 or teenagers. As per Wikipedia Contributors (2019), the amount of caffeine for mountain dew was found to be 76 mg.
3.3. Summary
As per the above analysis, the study focused on quantifying caffeine content in various energy drinks using HPLC. This chapter elaborately explains the result and represents the calibration curve and the caffeine quantification in energy drink samples. in addition, comparing observed concentrations with label claims as well as calibration curve was established using caffeine standards, demonstrating excellent linearity with a slope of 59666.50465 and a y-intercept of 3.7637. On the other hand, the caffeine content in different energy drinks varied significantly from that analysed in this chapter. Lastly, the HPLC method was highlighted for its effectiveness in separating and accurately quantifying caffeine.
4.0. Conclusion and Recommendation
4.1. Conclusion
As per the above analysis, it can be concluded that in caffeine direction analysis the HPLC method was more effective for quantifying caffeine content in various energy drink samples. In addition, the calibration curve showed excellent linearity that was only possible for its accuracy and exactitude of the method. As per the analysis, the pure form of coffee present in the market had the highest caffeine concentration at 785.93 mg/mL(for 1 gram of coffee beans) remarkably higher than the energy drink samples. In addition, the HPLC method could separate caffeine from other components in the complex energy drink matrices and create distinct caffeine peaks in the chromatograms. On the other hand, UV spectrophotometry was also utilised in this caffeine detection analysis but its result was less effective than the HPLC method. The UV spectrophotometry is a useful complementary technique but contains limitations in accurately quantifying caffeine in complex mixtures like energy drinks. However, this inaccuracy happens due to potential interference from other UV-absorbing components in the analysis. Also, there was no label claim for mountain dew drinks in the packaging and the amount of caffeine found was 63.57 mg which is much more for small children If they drink. So, the company should claim amount of caffeine present in the bottles as it is consumed by the small children’s and teenagers.
On the other hand, this report has analysed the multifaceted aspects of energy drinks which focused on the chemical composition of caffeine, and its effects on the human body. Apart from that, this quantitative research study highlights the primary composition of energy drinks which contributes to the stimulation of mental and physical performance. Caffeine was the featured ingredient of the study which coupled with the sugar produced quick energy through rapid glucose absorption. However, this mechanism gives consumers the sensation of heightened energy and improved performance. Lastly, the analysis report concludes that energy drinks often offer temporary rapid benefits to consumers but conduct severe risk factors with excessive intake.
4.2. Recommendations
Here, significant recommendations are highlighted that potentially better regulate caffeine content in energy drinks. In addition, improves consumer awareness and decreases potential health problems associated with excessive caffeine consumption from beverages like energy drinks.
- Should develop clear guidelines on the maximum recommended daily caffeine intake from energy drinks.
- As in mountain dew there was no information provided for the caffeine content so they should write amount of caffeine in the bottle so that people will be aware of the content of caffeine in the bottle.
- Established strong regulatory management given the interpretations between measured and labelled caffeine content. In addition, raised regulatory management may be certified to guarantee accuracy in the labelling of caffeine content in energy drinks.
- Established an educational campaign to inform consumers about the caffeine content in energy drinks and the potential health impacts of excessive caffeine consumption.
- Should sustain investigation on the long-term health effects of regular energy drink consumption.
- Should analyze a wider range of energy drink brands and flavours.
- Sustaining experiments with caffeine content with other ingredients in energy drinks.
- In the process of caffeine quantitation analysis here optimize the HPLC method to maintain accuracy but try another analytical technique like LC-MS/MS which is more accurate than the HPLC method.
- Appoint a regular monitoring program which follows caffeine content in energy drinks and assures compliance with labelling requirements.
- Motivate energy drink manufacturers to sustain research on low-containing caffeinated products that can be an alternative energy-boosting ingredient.
- Regulatory bodies should implement age restrictions on the sale of high-caffeine energy drinks when especially presented their popularity among youth.
Top Assignment Samples
References
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