Aspartame with saccharin

The main utihty of saccharin had been in beverages and as a table-top sweetener. Upon the approval of aspartame for carbonated beverages in 1983, aspartame displaced saccharin in most caimed and bottied soft drinks. However, saccharin is stiU used, usually blended with aspartame, in carbonated soft drinks dispensed from soda fountains. 

Intake estimates and calculations have been performed repeatedly for intense sweeteners for which probably the most extensive database among food additives exists. All studies and all calculations starting from reasonable assumptions indicate that only a minute proportion of consumers may come close to the ADI which may only seldom be exceeded by persons having food habits substantially different from the majority of the population. The best available data originate from a biomarker study on acesulfame and saccharin in which even the highest consumers among children consumed only a fraction of the ADI.29 Several intake studies were carried out on aspartame with the uniform result that no appreciable risk to exceed the ADI was found.14... 

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. 

Currently, aspartame is used in tabletop sweeteners (Equal in the U.S. F.ga in Quebec, Canada and Canderal in Europe and the tJK,). Aspartame currently is incorporated as the exclusive sweetening ingredient in nearly all diet soft drinks in the United States. In other countries, it may be blended, with saccharin at a level close to 50% of the saccharin level. Soft-dnnk manufacturers have taken some measures to enhance stability by raising pH slightly and by more closely controlling the inventory for carbonated soft drinks Notable differences in sweetness are perceived at a 40% loss in aspartame level. 

Neohesperidin dihydrochalcone has also been determined by ion-pair chromatography on LiChrospher 60 with a gradient of 15-95% methanol in 10 mM tetrabutylammonium hydrogen sulfate. No interference was observed from acesulfame-K, aspartame, and saccharin (66). 

Acesulfame-K, aspartame, cyclamate, saccharin LiChrosorb RP-18 0-20% Acetonitrile in H3P04 pH 2.34 with pentane-sulfonate (2 g/L) UV—254 nm 52... 

Acesulfame-K, aspartame, dulcin, saccharin /uBondapak C 18 10 gm, 300 X 3.9 mm Methanol 85% phosphoric acid, pH 6 with 34 mM tetra-ethylammonium hydroxide (2 8, v/v) UV—210nm 47... 

The taste profile of aspartame is similar to sucrose sweetness (Ripper et al., 1985). It is approximately 200 times as sweet as sucrose. It is synergistic with saccharin, cyclamate, stevioside, acesulfame K and many sugars, in particular fructose, but has little sweetness intensity synergy with sucralose. 

The increasing market demand for sweeteners resulted in the development of a number of chemicals. The major artificial sweeteners in the present market include acesulfame-K, alitame, aspartame, cyclamate, saccharin, and sucralose. Sweetness-intensity factors of several sweeteners compared with sucrose are given below ... 

Many excipients have been associated with adverse reactions in those ingesting drugs and vitamin/mineral formulations containing these compoundsJ78 79 Antioxidants (e.g., sodium sulfite, sodium and potassium bisulfites, and metabisulfites), bacterial preservatives (e.g., benzyl alcohol and benzalkonium chloride), artificial sweeteners (e.g., aspartame and saccharine), coloring agents (e.g., FD C yellow 5, blue 2, and red 40), and propylene glycol. A few examples of the toxic effects of these follow. 

Gas chromatography Acesulfame-K, aspartame, cyclamate, saccharin, and stevioside are determined by gas chromatography, but the main drawback of this technique is that a derivatization is required. Acesulfame-K is methylated with ethereal diazomethane, aspartame is converted into its N- 2-methylpropoxycarbonyl) methyl ester derivative, menthol and isobutyl chloroformate are used to convert aspartame to 3-[(isobutoxycarbonyl)amino]-4-[[a-(methoxycarbonyl)phenethyl]amino]-4-oxobutyric acid, cyclamate is determined as cyclohexene resulting from the reaction with nitrite, saccharin is converted to N-methylsaccharin, and stevioside is hydrolyzed. Detection is carried out utilizing flame-ionization, flame-photometric electron-capture detectors or nitrogen-phosphorus detection. 

CE with capacitively coupled contactless was used for the simple, rapid, and simultaneous determination of aspartame, cyclamate, saccharin, and acesulfame-K in commercial samples of soft drinks and tabletop sweetener formulations [37]. A buffer solution containing 100 mM tris(hydroxymethyl)aminomethane and 10 mM histidine was used as BGE. A complete separation of the analytes could be attained in less than 6 min. The detection limit was considered to be better than those usually obtained by CE with photometric detection. Recoveries ranging from 94% to 108% were obtained for samples spiked with standard solutions of the sweeteners. 

Bergamoa, A.B., Silvaa, J. A.F and Jesusa, D.P. (2011) Simultaneous determination of aspartame, cyclamate, saccharin and acesulfame-K in soft drinks and tabletop sweetener formulations by capillary electrophoresis with capacitively coupled contactless conductivity detection. Food Chem., 124, 1714-1717. 

Some sweeteners (aspartame, cyclamate, saccharin, and acesulfame K) were determined by CE-SIA with contactless conductivity detection (Stojkovic et al., 2013). The analyses were carried out in an aqueous running buffer consisting of 150 mM 2-(cyclo-hexylamino)ethanesulfonic acid and 400 mM tris(hydroxymethyl)aminomethane at pH 9.1 in order to render all analytes in the fully deprotonated anionic form. The four compounds were determined successfully in food samples the experimental set-up and typical analysis results are illustrated in Figure 2.9. Another SIA system combined with solenoid valves was used to automate an enzymatic method for the determination of aspartame in commercial sweetener tablets. The method involves the enzymatic conversion of aspartame to hydrogen peroxide by the chymotrypsin-alcohol oxidase system, followed by the use of 2,2-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ARTS) as electron donor for peroxidase. Chymotrypsin and alcohol oxidase enzymes were immobilized on activated porous silica beads (Pena et al., 2004). 

Bitencourt-Mendes et al. [90] described a method for saccharin determination in liquid sweetener products. The method is based on the precipitation reaction of Ag(I) ions with saccharin in aqueous medium (pH 3.0), using a FIA system with merging zones, the suspension was stabilized with 5 g/L Triton X-100. Based on interference studies performed with the substances commonly found in liquid sweeteners, such as sodium cyclamate, methylparaben, sodium aspartame, and benzoic and citric acids, at the analyte-to-interferent mole ratio of up to 1 10 no interference with the saccharin determination was observed. The presence of chloride ions interferes with the method, but a preceding liquid-liquid saccharin extraction with ethyl acetate was successfully employed to overcome this drawback. 

Capitan-Vallvey et al. [92] proposed an integrated solid-phase spectrophotometry FIA method for the simultaneous determination of the mixture of saccharin and aspartame. The procedure is based on online preconcentration of aspartame on a Cjj silica gel minicolumn and separation from saccharin, followed by measurement at 210 nm of the absorbance of saccharin, which is transiently retained on the adsorbent Sephadex G-25 placed in the flow-through cell of a monochannel FIA setup using pH 3.0 orthophospho-ric acid-dihydrogen phosphate buffer, 3.75 x 10 M, as carrier. Subsequent desorption of aspartame with methanol enables its determination at 205 nm. 

Sucrose occupies a unique position in the sweetener market (Table 3). The total market share of sucrose as a sweetener is 85%, compared to other sweeteners such as high fmctose com symp (HFCS) at 7%, alditols at 4%, and synthetic sweeteners (aspartame, acesulfame-K, saccharin, and cyclamate) at 4%. The world consumption of sugar has kept pace with the production. The rapid rise in the synthetic sweetener market during 1975—1995 appears to have reached a maximum. 

Saccharin imparts a sweetness that is pleasant at the onset but is followed by a lingering, bitter aftertaste. Sensitivity to this bitterness varies from person to person. At high concentration, however, most people can detect the rather unpleasant aftertaste. Saccharin is synergistic with other sweeteners of different chemical classes. For example, saccharin—cyclamate, saccharin—aspartame, saccharin—sucralose, and saccharin—aUtame combinations all exert synergy to various degrees. The blends, as a rule, exhibit less aftertaste than each of the component sweeteners by themselves. 

Finally, some amphiphilic sweeteners, eg, aspartame, saccharin, and neohesperidin dihydrochalcone, have been shown to be capable of stimulating a purified G-protein direcdy in an in vitro assay (136). This suggests some sweeteners may be able to cross the plasma membrane and stimulate the G-protein without first binding to a receptor. This type of action could explain the relatively longer response times and the lingering of taste associated with many high potency sweeteners. 

The artificial sweeteners erythritol, sodium saccharin, and aspartame (Fig. 25) were also studied. Figure 26 shows potential oscillation in the presence of these artificial sweeteners [22]. The oscillation modes of these substances differed considerably. For erythritol above 10 mM, Fa.sds slightly shifted to more negative potentials. and Fb.sds were essentially unaffected by this sweetener. Erythritol thus induces change in the oscillation mode in much the same way as sugars. At 1 mM-1 M sodium saccharin, E and Fa.sds shifted to more negative values with increase in its concentration. For aspartame at less than 10 mM, there was no change in potential. 

Instant tea is also marketed with lemon flavor and with flavor and sweetener. The latter may be sugar, saccharin, or aspartame. 

Chen et al. (1997a) analysed sodium saccharin in soft drinks, orange juice and lemon tea after filtration by injection into an ion-exclusion column with detection at 202 nm. Recoveries of 98-104% were obtained. They reported that common organic acids like citric and malic and other sweeteners did not interfere. Qu et al. (1999) determined aspartame in fruit juices, after degassing and dilution in water, by IC-PAD. The decomposition products of aspartame, aspartic acid and phenylanaline were separated and other sweeteners did not interfere. The recoveries of added aspartame were 77-94%. Chen et al. (1997b) separated and determined four artificial sweeteners and citric acid. 

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. 

Fig. 3.138. Electropherogams showing the separation of caffeine (1), aspartame (2), brilliant blue FCF (3), green S (4), sorbic acid (5), benzoic acid (6), saccharin (7), acesulfame K (8), sunset yellow FCF (9), quinoline yellow (10), carmoisine (11), ponceau 4R (12), black PN (13), using 20 mM carbonate buffer, pH 9.5 containing (a) no SDS, (b) 50 mM SDS, (c) 75 mM SDS. A 48.5 X 50 /tm I.D. fused-silica capillary was used and absorbance was measured at 200 nm. Reprinted with permission from R. A. Frazier et al. [184],...

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