Soft drinks, caffeinated

Caffeine is derived by extraction of coffee beans, tea leaves, and kola nuts. It is also prepared synthetically. Much of the caffeine of commerce is a by-product of decaffeinized coffee manufacture. The compound is purified by a series of recrystallizations. Caffeine finds use in medicine and in soft drinks. Caffeine is also available as the hydrobromide and as sodium benzoate, winch is a mixture of caffeine and sodium benzoate, containing 47-50% anhydrous caffeine and 50-53% sodium benzoate. This mixture is more soluble in water than pure caffeine. A number of nonprescription (pain relief) drugs contain caffeine as one of several ingiedients. Caffeine is a known cardiac stimulant and in some persons who consume significant amounts, caffeine can produce ventricular premature beats. 

As with the other additives used in soft drinks, caffeine and quinine can be, and often have been, detected using the same HPLC method used for other materials, such as in the method published by Williams (1986). This method separates most of the major additives used in soft drinks in a short time (4-5 min). Although some of the resolutions are not quite baseline, as would be expected in such a short analysis time, and not all of the synthetic colours are separated from each other, this is still a very impressive method. 

Additive stimulant effects of caffeine Caffeine is present in many products that contain ephedra alkaloids, and those who take these products might also be consuming considerable quantities of caffeine in coffee, tea, and soft drinks. Caffeine can enhance the undesirable effects of ephedrine on the heart, blood supply system, and brain function. 

In some cases, small amount of caffeine is added to soft drinks. Caffeine has a classic bitter taste that enhances other flavors. UV spectrometry, HPLC, and CE are used for the determination of caffeine in beverages. All of the above methods require sample preparation. FTIR spectroscopy with chemometrics, using partial least squares first derivative spectrum in the region between 2800 and 3000 cm have been developed to directly determine the caffeine in soft drinks. 

Caffeine, benzoic acid, and aspartame in soft drinks are analyzed by three methods. Using several methods to analyze the same sample provides students with the opportunity to compare results with respect to accuracy, volume of sample required, ease of performance, sample throughput, and detection limit. 

Diet soft drinks contain appreciable quantities of aspartame, benzoic acid, and caffeine. What is the expected order of elution for these compounds in a capillary zone electrophoresis separation using a pH 9.4 buffer solution, given that aspartame has pJC values of 2.964 and 7.37, benzoic acid s pfQ is 4.2, and the pfQ for caffeine is less than 0. 

Colas represent the largest segment of the U.S. soft drink market followed by lemon—lime brands. Pepper-type, juice-based, toot beer, and orange flavored soft drinks represent two to five percent of the total soft drink market (Fig. 4). Diet and caffeine-free categories represent the fastest growing segments of the market. 

Most soft drinks are characterized by carbonated water, sugar, and caffeine. Variations in soft drinks generally advertise either flavor differences, or the absence of one or more of the three main ingredients. 

Caffeine is added as a stimulant, but it has a bitter taste that is a component in many soft drinks. 

Caffeine is an addictive drug used in soft drinks as a stimulant. It occurs naturally in coffee, tea, and chocolate. 

The basic process outline is depicted in Figure 5.2 moist un-roasted coffee beans and CO2 are fed counter-currently into the extractor under supercritical conditions. Caffeine is selectively extracted into the CO2 and this stream is led to a water-wash column to remove caffeine at a reduced pressure, the CO2 being recycled back to the extraction column. Extraction of the caffeine into water is necessary to avoid dropping the CO2 pressure too low, since compression is energy-intensive. There is now the problem of separating the caffeine (which is used in soft drinks and pharmaceu-... 

Determination of caffeine in soft drinks was undertaken using the aerosol alkali flame ionization detector.24 Soft drinks studied were Coke, Diet Coke, Pepsi, Diet Pepsi, Dr. Pepper, and Mountain Dew. A sample clean-up and concentration procedure is employed followed by GC separation with alkali flame ionization detection. Results showed that Coke, Diet Coke, Pepsi, Diet Pepsi, Dr. Pepper, and Mountain Dew contained 41 2, 52 2, 43 4, 35 9, 46 6, and 60 15 mg caffeine per 355-ml serving. These values compared favorably with levels reported in the literature. 

Significant scientific attention has focused on caffeine and its health effects. However, limited data is available for the actual dietary consumption of caffeine or theobromine from individual foods. Even less data exists on the contribution of cocoa and chocolate foods to methylxanthine intake. In children and teenagers, the major dietary source of caffeine was found to be tea, followed by soft drinks and coffee, respectively. Although chocolate foods and beverages ranked the lowest of these dietary sources to provide caffeine, they do constitute the major source of dietary theobromine. In order to gain a better insight into the amount of methylxanthines consumed via the diet, more studies on the methylxanthine content of chocolate foods, as well as beverages, are needed. 

This chapter will cover the production of coffee, tea, and cocoa, which comprise the primary crops that account for the majority of worldwide caffeine consumption. Caffeine-containing crops and products comprise a large share of the international market and are primary commodities for many national economies.3 4 Trade of such products is also important in the understanding of availability, market demand, and overall exposure to caffeine from various sources. Information is presented to a lesser degree for soft drinks, many of which do contain caffeine and are consumed primarily in the industrialized nations. Another source of caffeine exposure which contributes less than any beverages and foods under consideration are prescription and non-prescription medications, which are described in lesser detail. 

Caffeine consumption is primarily due to coffee, tea and soft drinks. In the U.S., it is estimated that coffee contributes to 75% of the total caffeine intake, tea is 15%, and soda with caffeine accounts for 10% 5 chocolate and other caffeine-containing foods and medications contribute relatively little to overall caffeine exposure. Caffeine also varies by sources tea leaves contain 1.5 to 3.5% caffeine kola nuts contain 2% caffeine and roasted coffee beans contain 0.75 to 1.5% caffeine.6 Coffee varies in caffeine content some analyses have estimated that caffeine may range from 0.8 to 1.8%, depending on the type of coffee.7 Crops of coffee, tea, and cocoa are very similar in their production periods and their useful life in production. Typically coffee, tea, and cocoa trees can be productive with crops every 5 years for a total period of 40 years,8 or an estimated 8 yields per tree. 

Caffeine The psychostimulant found in colfee, tea and a wide variety of carbonated soft drinks. Chemically related to the purine neurotransmitter adenosine, the drug blocks adenosine receptors in the nervous system. 

There is a recent trend towards simultaneous CE separations of several classes of food additives. This has so far been applied to soft drinks and preserved fruits, but could also be used for other food products. An MEKC method was published (Lin et al., 2000) for simultaneous separation of intense sweeteners (dulcin, aspartame, saccharin and acesulfame K) and some preservatives (sorbic and benzoic acids, sodium dehydroacetate, methyl-, ethyl-, propyl- and isopropyl- p-hydroxybenzoates) in preserved fruits. Ion pair extraction and SPE cleanup were used prior to CE analysis. The average recovery of these various additives was 90% with good within-laboratory reproducibility of results. Another procedure was described by Frazier et al. (2000b) for separation of intense sweeteners, preservatives and colours as well as caffeine and caramel in soft drinks. Using the MEKC mode, separation was obtained in 15 min. The aqueous phase was 20 mM carbonate buffer at pH 9.5 and the micellar phase was 62 mM sodium dodecyl sulphate. A diode array detector was used for quantification in the range 190-600 nm, and limits of quantification of 0.01 mg/1 per analyte were reported. The authors observed that their procedure requires further validation for quantitative analysis. 

Use most widely used stimulant in the world Source coffee, tea, cola and other soft drinks, chocolate Recommended daily intake the US Food and Drug Administration (FDA) advised pregnant women to avoid caffeine-containing foods and drugs, if possible, or consume them only sparingly ... 

How many hours elapse before you reach for that second cup of coffee Many of us have learned by practice that when our blood caffeine levels decline too far, we need to boost them back up with a second cup of coffee, tea, or a can of soft drink. 

Many people start consuming caffeine at an early age. It is not uncommon for schools to have soft drink machines and even coffee stands at and certainly near schools. Middle and high school students are well aware of the stimulant properties of caffeine. Is it appropriate to have soft drink machines in schools, which encourages caffeine consumption ... 

Caffeine is the most widely consumed stimulant drug in the world. It occurs naturally in coffee, tea, and the cola nut and is added to many soft drinks. Many of us consume coffee and soft drinks because of the desirable stimulatory effects produced by caffeine many of us have consumed too much caffeine and felt the consequences. The undesirable effects of caffeine, the agitation, the inability to concentrate, the mild tremors, and the general unpleasantness, are a form of neurotoxicity. Literally your brain, and more specifically, the adenosine receptors in your brain, has too much caffeine. These effects are a reversible form of neurotoxicity. Fortunately, we metabolize caffeine quickly and the undesirable effects end. By experience we have learned how to moderate our caffeine consumption to avoid the unpleasant side effects. A great deal of money is made from the neuroactive and physiological effects of caffeine. You can learn more about this fascinating drug in the chapter on caffeine. 

For the analysis and separation of benzoic acid, caffeine, aspartame, and saccharin in dietetic soft drinks, a HPLC system consisting of a Varian MCH-5N-CAP 150 x 4.6 mm column and a variable wave length UV/VIS detector was recommended [32]. The mobile phase is a gradient, beginning with 90% 0.01 M KH2PO4 (pH = 2) and methanol, and ending in 25 minutes with 60 % buffer / 40 % methanol. 

Asa Griggs Chandler, another, more astute pharmacist who saw the potential in Coca-Cola as a soft drink rather than a tonic. In the next 15 years, he made a fortune from the Coca-Cola company and founded what was to become the world s best known multinational. The formula of Coca-Cola has chtmged over the years and the coca extract was removed in the early twentieth century and many decades later caffeine-free versions became available. Competitors produced their own versions of what became known as cola drinks, nearly always containing caffeine and a variety of natural and synthetic flavouring (Figure 2.7). 

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