Sweetener intense

Fmctose is sweeter than sucrose at low temperatures (- S C) at higher temperatures, the reverse is tme. At 40°C, they have equal sweetness, the result of a temperature-induced shift in the percentages of a- and P-fmctose anomers. The taste of sucrose is synergistic with high intensity sweeteners (eg, sucralose and aspartame) and can be enhanced or prolonged by substances like glycerol monostearate, lecithin, and maltol (19). 

A chlorination process (20,21,44—46) converts sucrose into sucralose [56038-13-2] (4,l, 6 -trichloro-4,l, 6 -trideoxy-galactosucrose), a heat-stable, noncariogenic, noncaloric, high intensity sweetener. Sucralose is approved for food use in Canada, Australia, and Russia. It is not yet approved for use in the United States. 

Examination of several classes of intense sweeteners showed the existence of potential x sites whose relation to the AH,B unit is identical to the Kier proposal (9-13) (Fig. 11). 

The metabolic and pharmacokinetic profile of sucralose (this is a novel intense sweetener with a potency about 600 times that of sucrose) in human volunteers was studied by Roberts and coworkers [82]. Part of this study was realized using PLC in the following chromatographic system in which the stationary phase was silica gel and the mobile phase was ethyl acetate-methanol-water-concentrated ammonia (60 20 10 2, v/v). Separated substances were scraped off separately, suspended in methanol, and analyzed by filtration, scintillation counting, or enzymatic assay. It was shown that the characteristics of sucralose include poor absorption, rapid elimination, limited conjugative metabolism of the fraction absorbed, and lack of bio-accumulative potential. 

FDA Approves New High-Intensity Sweetener Sucralose. FDA Talk Paper T98-16, April 1,1998, The Diabetes Monitor, http //www.diabetesmonitor.com/sucralos.htm... 

Synthesis of (—)-monatin (524), a high-intensity sweetening agent, was achieved by chelation-controlled cycloaddition of chiral oxazinone-derived nitrone (16 ) to allyl alcohol (520) in the presence of MgBr2 OEt2 (Scheme 2.248) (746). 

High intensity induced-roll magnetic separators, 15 453—454 High intensity sweeteners, 12 38, 41—43 High internal-efficiency structures, 14 844-845... 

HPLC method for simultaneous determination in intense sweeteners in foodstuffs. 

Work programme of CEN TC 275 Working Group 2 Intense Sweeteners Published standards... 

Sweeteners can be roughly divided into two groups bulk and intense sweeteners. Prodolliet (1996) and Gloria (2000) reviewed thoroughly the analysis and properties of intense sweeteners acesulfame-K, alitame, cyclamate, aspartame, glycyrrhizin, neohesperidin DC, saccharin, stevioside, sucralose and thaumatin. They are generally used in low calorie products such as diet... 

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. 

Enzymatic assay techniques have been developed for several additives by Merck. BIOQUANT kits are available for aspartame (intense sweetener) and nitrate (preservative). Gromes et al. (1995) applied the Bioquant kit to determination of aspartame in yoghurt, quark and confectionery. For low concentrations of aspartame a blank correction procedure was necessary. Recoveries of aspartame were in the range 93-102%. 

Sweetness free, or at least virtually free, from calories establishes the need for intense sweeteners while suitability for diabetics, absence of carcinogenicity with functionality similar to sucrose and related carbohydrates form the basis for application of bulk sweeteners. 

Because of their non-metabolism or insignificant contribution to the calorie content of a diet, intense sweeteners seem to be an ideal means to lower calorie intake in sweet-tasting foods and beverages. Such a simple approach, however, would not take into consideration that function and properties of bulk sweeteners determine characteristics of many sweet-tasting products, e.g. texture, appearance and shelf stability amongst others.3... 

Intense sweeteners are characterised by a high sweetness intensity on a weight basis. Sweetness intensity values differ for general comparisons standard sweetness intensity values are often used with sucrose being the standard with a sweetness intensity of 1. Sweetness intensities depend on a number of factors, e.g. concentration and presence of flavours or taste components. They are therefore not a suitable tool for calculation of use concentrations except for very preliminary approaches. 

Taste characteristics in general determine applicability of intense sweeteners. A time-intensity profile of sweetness perception similar to sucrose is desirable, and a delay in sweetness onset or a lingering sweetness are generally perceived as less pleasant. Side-tastes like bitter, liquorice or metallic taste are disadvantages which limit the applicability of some sweeteners. 

Intense sweeteners have low functionality besides their sweet taste. Therefore intense sweeteners cannot be used as the only sweetening agents whenever at least one of the mentioned functions is important for a product. Combinations of intense and bulk sweeteners will come close to sucrose and other sweet carbohydrates in functionality and taste, and can therefore be considered as an interesting alternative to sugar in applications requiring functional properties. They are often used in addition to bulk sweeteners in the typical application of these. 

Many sweet-tasting foods and beverages, however, do not require the functionality of sucrose and sweet carbohydrates. These products are the typical fields of application of intense sweeteners. As bulk sweeteners are used for taste reasons rather than functionality these products offer possibilities to reduce calories without sacrificing any important product characteristic. Intense sweeteners are used as the sole sweetening agents in beverages, table-top sweeteners like powder or tablets, desserts and dairy products besides a variety of further areas of lesser importance. 

The available intense sweeteners belong to very different structural classes of sweeteners (Table 10.1). They were normally discovered by chance. All internationally important sweeteners are produced synthetically and only two less important products are isolated from plants. 

Metabolism via normal metabolic pathways or fast excretion without metabolism are desirable characteristics. Some intense sweeteners are excreted unchanged while others are metabolised. Bulk sweetener absorption is lower and slower than for carbohydrates and results in reduced caloric availability which is partly due to metabolites formed by intestinal bacteria. Such metabolites and osmotic effects of not fully absorbed bulk sweeteners can cause laxative effects. Generally, the calorific value of bulk sweeteners is lower than for carbohydrates. Intense and bulk sweeteners are, as far as they are metabolised, not dependent on insulin. They are therefore acceptable for diabetics as part of a suitable diet. 

Saccharin is l,2-benzisothiazol-3(2H)-on-1,1-dioxide, often also called o-benzoic acid sulfimide. Discovered in 1878, it is the oldest available intense sweetener. 

Other than the sweeteners discussed so far thaumatin is a polypeptide consisting of amino acids commonly found in food proteins. It is quickly and completely digested like proteins and did, after demonstration of its metabolic characteristics, only require a rather limited set of safety data. In contrast to the other intense sweeteners the ADI of thaumatin is not specified , as for substances of similar composition.27 It is approved in many countries but, owing to its flavour enhancing properties, is often used as a flavour enhancer rather than a sweetener. 

The intake of food additives in general and of intense sweeteners in particular has been discussed in the course of the last few years. Interest has focused on intense sweeteners, although the database for sweeteners and possibilities to exclude excess intake above the acceptable levels on the basis of calculations and estimates are much better than for most other components. 

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... 

The applicability of bulk and intense sweeteners is determined by their regulatory status. Bulk and intense sweeteners require food additive approval in many countries. 

An important step and for some countries even a prerequisite before food additive approval is endorsement for food use by international scientific bodies like the JECFA or the European SCF. These committees evaluate the safety data, identify a no-observed-effect level and allocate an ADI, usually by applying a safety factor of 100 to the ADI. While numerical values have been allocated for all intense sweeteners, the ADIs for bulk sweeteners are normally not specified as any numerical limitation would not be reasonable for these substances. 

In the USA the available bulk sweeteners are listed under different provisions, like food additive, interim status, GRAS (Generally Recognised As Safe) or GRAS by self-determination or self-affirmation of the manufacturers. Intense sweeteners require food additive approval which includes a listing of the approved fields of use or may be a listing as a general purpose sweetener.32... 

Beyond national approvals the Codex Alimentarius is developing a General Standard for Food Additives which will be the applicable basis for international trade. All and only sweeteners endorsed for food use by JECFA are/or will be listed in this standard. For bulk sweeteners the standard has progressed to permanent while the part dealing with intense sweeteners is still under discussion. 

Table 10.3 Approved use levels for intense sweeteners in some categories of sugar-free or calorie-reduced products in the European Union (values in mg/kg or mg/1)... 

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