Аспартам химические свойства, назначение, производство
Описание
Aspartame is the most popular artificial sweetener in the United States. It is sold as sweeteners such as NutraSweet and Equal, but it is also incorporated into thousands of food products.
Химические свойства
Aspartame (N-L-aspartyl-L-phenylalanine-1-methyl ester, 3-amino-N-(a-carbomethoxy-
phenethyl)-succinamic acid-N-methyl ester) is an intense sweetener widely
used in foods and beverages. Its solubility in water is approximately 10 g/L at room
temperature. Aspartame is not fully stable under common processing and storage
conditions of foods and beverages with the highest stability around pH 4.3.
Aspartame is about 200 times sweeter than sucrose with a clean, but slightly
lingering sweetness. It is used as the single sweetener, but often also in blends with other intense sweeteners owing to synergistic taste enhancement and taste quality
improvement often seen in such blends.
In the European Union, aspartame is approved as E 951 for a large number of
food applications. In the United States, it is approved as a multipurpose sweetener
for food and beverage uses and it is also approved in many other countries.
История
Aspartame was discovered accidentally in 1965 during a search for drugs to treat gastric ulcers. James M. Schlatter, an organic chemist working for G. D. Searle & Company, was using aspartyl-phenylalanine methyl ester (aspartame) in a synthesis procedure and inadvertently got some of the compound on his hands.
Использование
Aspartame is a high-intensity sweetener that is a dipeptide, provid-
ing 4 cal/g. it is synthesized by combining the methyl ester of
phenylalanine with aspartic acid, forming the compound n-l-alpha-
aspartyl-l-phenylalanine-1-methyl ester. it is approximately 200
times as sweet as sucrose and tastes similar to sugar. it is compara-
tively sweeter at low usage levels and at room temperature. its mini-
mum solubility is at ph 5.2, its isoelectric point. its maximum
solubility is at ph 2.2. it has a solubility of 1% in water at 25°c. the
solubility increases with temperature. aspartame has a certain insta-
bility in liquid systems which results in a decrease in sweetness.
it decomposes to aspartylphenylalanine or to diketropiperazine
(dkp) and neither of these forms is sweet. the stability of aspartame
is a function of time, temperature, ph, and water activity. maximum
stability is at approximately ph 4.3. it is not usually used in baked
goods because it breaks down at the high baking temperatures. it
contains phenylalanine, which restricts its use for those afflicted
with phenylketonuria, the inability to metabolize phenylalanine.
uses include cold breakfast cereals, desserts, topping mixes, chew-
ing gum, beverages, and frozen desserts. the usage level ranges from
0.01 to 0.02%.
Определение
ChEBI: A dipeptide composed of methyl L-phenylalaninate and L-aspartic acid joined by a peptide linkage.
Подготовка
By coupling the amino acids L-phenylalanine and L-aspartic acid, and the esterification of the carboxyl group of the
phenylalanine moiety to produce the methyl ester. This esterification can occur before or after coupling. The crystallized slurry is
centrifuged and the resulting “wet-cake” is washed to remove impurities.
Методы производства
Aspartame is produced by coupling together L-phenylalanine (or Lphenylalanine
methyl ester) and L-aspartic acid, either chemically or
enzymatically. The former procedure yields both the sweet aaspartame
and nonsweet β-aspartame from which the α-aspartame
has to be separated and purified. The enzymatic process yields only
α-aspartame.
Общее описание
Asp-Phe methyl ester (aspartame, APM, ASP), a dipeptide ester, is made up of phenyl alanine and aspartic acid. Its genotoxic effects have been investigated. Its interaction with certain hydrocolloids has been studied.
Фармацевтические приложения
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.
Unlike some other intense sweeteners, aspartame is metabolized
in the body and consequently has some nutritive value: 1 g provides
approximately 17 kJ (4 kcal). However, in practice, the small
quantity of aspartame consumed provides a minimal nutritive
effect.
Профиль безопасности
Human systemic effects byingestion: allergic dermatitis. Experimental reproductiveeffects. When heated to decomposition it emits toxicfumes of NOx.
Экологическая судьба
Aspartame is nontoxic. However, individuals with the rare,
genetic disease, phenylketonuria (PKU), cannot properly
metabolize phenylalanine. Such individuals are detected by
testing at birth and placed on special low-phenylalanine diets
to control their blood phenylalanine concentrations. Thus,
PKU individuals need to be aware that aspartame is a source of
phenylalanine.
Метаболический путь
The rate of aspartame degradation is faster in a
phosphate buffer solution than in a citrate buffer
solution at the same pH and buffer concentration. The
primary mechanism by which aspartame degrades, the
formation of diketo piperazine, involves the
nucleophilic attack of carbonyl by the free amine,
which requires proton transfer.
хранилище
Aspartame is stable in dry conditions. In the presence of moisture,
hydrolysis occurs to form the degradation products L -aspartyl-Lphenylalanine
and 3-benzyl-6-carboxymethyl-2,5-diketopiperazine
with a resulting loss of sweetness. A third-degradation product is
also known, β-L-aspartyl-L-phenylalanine methyl ester. For the
stability profile at 258℃ in aqueous buffers.
Stability in aqueous solutions has been enhanced by the addition
of cyclodextrins, and by the addition of polyethylene glycol 400
at pH 2. However, at pH 3.5–4.5 stability is not enhanced by the
replacement of water with organic solvents.
Aspartame degradation also occurs during prolonged heat
treatment; losses of aspartame may be minimized by using processes
that employ high temperatures for a short time followed by rapid
cooling.
The bulk material should be stored in a well-closed container, in
a cool, dry place.
Несовместимости
Differential scanning calorimetry experiments with some directly
compressible tablet excipients suggests that aspartame is incompatible
with dibasic calcium phosphate and also with the lubricant
magnesium stearate. Reactions between aspartame and sugar
alcohols are also known.
Регуляторный статус
Accepted for use as a food additive in Europe and in the USA.
Included in the FDA Inactive Ingredients Database (oral powder for
reconstitution, buccal patch, granules, syrups, and tablets).
Included in nonparenteral medicines licensed in the UK. Included
in the Canadian List of Acceptable Non-medicinal Ingredients.
Аспартам препаратная продукция и сырье
сырьё
препарат