Sweetening agents aspartame

The —CO—NH - link shown in the red box is called a peptide bond, and each monomer used to form a peptide is called a residue. A typical protein is a polypeptide chain of more than a hundred residues joined through peptide bonds and arranged in a strict order. When only a few amino acid residues are present, we call the molecule an oligopeptide. The artificial sweetening agent aspartame is a type of oligopeptide called a dipeptide because it has two residues. 

In nature, the amino acids are combined to give proteins with hundreds or even thousands of amino acids in each one. Small assemblies of amino acids are known as peptides and die amide bond that links them is called a peptide bond. One important dipeptide is the sweetening agent aspartame, whose synthesis was discussed in Chapter 25. It is composed (and made) of the amino acid aspartic acid (Asp) and the methyl ester of phenylalanine. Only this enantiomer has a sweet taste and it is very sweet indeed—about 160 times as sweet as sucrose. 

In the synthesis of peptides such as bradykinin the use of the configurationally correct aminoacid is obligatory and semi-synthesis and total synthesis here become indistinguishable. By contrast the unnatural dipeptide sweetening agent, aspartame (ref. 106) illustrates the scope for semi-synthesis. 

The next example has two interesting features. An intermediate for the synthesis of the sweetening agent Aspartame has been synthesised from Z—Asp(OBzl)—OH... 

In addition to sucrose, a number of other sweetening agents have been utilized in foods and pharmaceuficals over the years, including dextrose, mannitol, sorbitol, aspartame, saccharin, and others. Some sweeteners, such as sucrose, aid in preserving the product. 

Aspartame, discovered by Mazur in 1969 (5), is 200 times sweeter than sucrose. Aspartame has a large commercial market as an artificial sweetening agent. It is apparent that the sweetness exhibited by aspartame requires amino (AH, electropositive) and carboxyl (B, electronegative) groups of aspartic acid moiety and the hydrophobic side chain (X) of the phenylalanine moiety (4). The sweetness of aspartame is exhibited by the trifunctional units AH, B, and X. It is thought that when the trifunctional units of aspartame, X, AH, and B, fit the corresponding receptor sites, a sweet taste is produced. 

Aspartame (a-L-aspartyl-L-phenylalanine 1-methyl ester) is a sweetening agent that is roughly 200 times sweeter than sucrose. Routes for preparing this compound are described in U.S. 3,492,131, U.S. 4,440,677 (both to G. D. Searle Co.), and U.S. 5,476,961 (to the NutraSweet Company). Determine which route gives the lowest cost of production. 

Aspartame is used as an intense sweetening agent in beverage products, food products, and table-top sweeteners, and in pharmaceutical preparations including tablets, powder mixes, and vitamin preparations. It enhances flavor systems and can be used to mask some unpleasant taste characteristics the approximate sweetening power is 180-200 times that of sucrose. 

Amino-N-(a-methoxycarbonylphenethyl) succinamic acid 3-Amino-N-(a-carboxyphenethyl)succinamic acid N-methyl ester APM Asp-phe-ome Aspartam Aspartame Aspartame, L,L-a- Aspartamo Aspartamum Aspartylphenylalanine methyl ester L-Aspartyl-L-phenylalanine methyl ester Canderel CCRiS 5456 DIpeptide sweetener EINECS 245-261-3 Equal HSDB 3915 Methyl aspartylphenylalanate Methyl L-aspartyl-L-phenylalanine Methyl L-a-aspartyl-L-phenylalanate Methyl N-L-a-aspartyl-L-phenylalaninate 1-Methyl N-L-a-aspartyl-L-phenylalanate Nutrasweet L-Phenylalanine, L-a-aspartyl-, 2-methyl ester L-Phenylalanine, N-L-a-aspartyl-, 1-methyl ester SC 18862 Succinamic acid, 3-amino-N-(a-carboxyphenethyl)-, N-methyl ester, Sweet dipeptide Tri-sweet, A sweetening agent Crystals mp = 246-247° [a]8 = -2,3° (IN HCI). Searte 6.D. Co. 

Among the food science developments helpful to diabetics have been the discovery and commercial distribution of several synthetic noncarbohydrate sweetening agents. Three that have been approved by the American Diabetes Association are saccharin, acesulfame-K, and aspartame ... 

The use of foods containing artificial sweetening agents such as saccharin and aspartame, and the use of polyols like mannitol, soibitol, and xylitol, may decrease the incidence of caries, since bacteria of the mouth cannot ferment these sweeteners to acids. 

At least 10 of jujube s saponins (e.g. ziziphin, jujubasaponins, and jujuboside B) are sweetness inhibitors that reduce the sensation of sweet taste (elevate the sweetness threshold) of glucose, fructose, aspartame, and other sweetening agents. No taste modifying effect was observed with bitter, salty, or sour flavors. 

Saccharin also comes into this category and so would other sweetening agents such as cyclamates and aspartame if and when they are permitted to be used. 

Nowadays a wide variety of food ingredients are already produced in an encapsulated form. These comprise artificial sweeteners (aspartame), flavouring agents such as oils or spices (with desirable flavour but possibly undesirable odour), natural colorants (e.g., p-carotene, turmeric), preservatives, acids (citric, lactic and ascorbic), bases, buffers, enzymes, lactic acid bacteria, and some antioxidants (Kirby, 1991 Gibbs et al, 1999 Chen et al, 2006b Ubbink and Kruger, 2006 Augustin and He-... 

Flavoring agents -food toxicants m [FOOD TOXICANTS, NATURALLY OCCURRING] (Vol 11) -for pharmaceuticals [PHARMACEUTICALS] (Vol 18) -reactions with aspartame [SWEETENERS] (Vol 23) -for tea [TEA] (Vol 23)... 

Aspartame contains a free Af-terminal amino group. In its deprotonated form, this could be expected to react with carbonyl compounds, forming Schiff base compounds. Some evidence has been obtained for this type of reaction, involving aspartame and flavoring agents [41]. A similar explanation might also apply to the interactions with ascorbic acid and carbohydrate sweeteners described in the previous paragraph. 

L-Aspartic acid (12) is an industrially important, large volume, chiral compound. The primary use of aspartic acid in the fine chemical arena is in the production of aspartame, a high potency sweetener (Chapter 31). Other uses of L-aspartate include dietary supplements, pharmaceuticals, production of alanine (by decarboxylation), antibacterial agents, and lubricating compounds. There have been a number of reviews on L-aspartate production.53 56... 

There has been considerable interest from both academics and industry in this reaction since 1980. There are a wide number of uses for the amido acid products surface-active agents and specialty surfactants (Cio-Cie amido acids), intermediates for aspartame sweeteners (phenylalanine), food additives (monosodium glutamate), and chelating agents (iminoacetic acid and polyamido acids). Knifton (Texaco) has done extensive studies of this reaction, as have Ojima and coworkers. ... 

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