изомальт химические свойства, назначение, производство
Описание
Isomalt is an equimolar mixture of oc-D-glucopyranosyl-1,6-
D-sorbitol (GPS) and α-D-glucopyranosyl-l,l-D-mannitol (GPM).
The production process of isomalt involves two essential steps. In
the first step, the 1,2 -glycosidic linkage between the glucose and
the fructose moiety of sucrose is rearranged by an immobilized
enzyme system to a 1,6 -glycosidic linkage, which is more stable
and characteristic for the cross linkage in the amylopectin fraction
of native starch. In the second step, the rearranged sucrose molecule, i.e., isomaltulose, is hydrogenated to the corresponding sugar
alcohols. Isomalt is commercially available as a dry, white crystalline powder which is about half as sweet as sucrose.
In vitro studies with intestinal disaccharidases from mammals
demonstrated that isomalt is cleaved much more slowly than
sucrose or maltose. A slight inhibitory effect on maltose hydrolysis
and on the active transport on glucose has also been observed.
Ingested isomalt is partly hydrolyzed in the small intestine and
slowly absorbed in the form of glucose, sorbitol, and mannitol.
The intact portion of isomalt, as well as some unabsorbed sorbitol
and mannitol, reaches the distal parts of the gut where these
products are fermented to volatile fatty acids.
Химические свойства
Isomalt is a more or less equimolar mixture of 1-O-a-D-glucopyranosy-D-mannitol-
dihydrate and 6-O-a-D-glucopyranosyl-D-sorbitol. Different production
conditions, however, allow variations in the ratio of the two products. The solubility
in water is about 24.5 % (w/w) at room temperature, but varies with the
composition and increases with increasing temperature. In addition to the dry
isomalt, a syrup is available.
Isomalt is, depending on the concentration, approximately 45–60 % as
sweet as sucrose, stable under normal processing conditions of foods, and
noncariogenic.
In the European Union, isomalt is approved as E 953 for a large number of food
applications. It is GRAS in the United States and also approved in many other
countries.
Owing to its low glycemic index, isomaltulose, an intermediate of the production,
has found increasing interest as a food ingredient in recent years.
История
It is claimed that isomalt is odorless, white, crystalline, and sweet tasting without the accompanying taste or aftertaste. Sweetening power is from 0.45 to 0.6 that of sucrose. A synergistic effect is achieved when isomalt is combined with other artificial sweeteners and sugar substitutes. Principal applications are in confections, pan-coated goods, and chewing gum. The substance was approved for use in most European countries in 1985. Classification of isomalt as a GRAS substance was petitioned in the United States. (GRAS = generally regarded as safe.)
Использование
analgesic, NSAID
Методы производства
Isomalt is produced from food-grade sucrose in a two-stage process.
Beet sugar is converted by enzymatic transglucosidation into the
reducing disaccharide isomaltulose. This undergoes catalytical
hydrogenation to produce isomalt.
Фармацевтические приложения
Isomalt is a noncariogenic excipient used in a variety of
pharmaceutical preparations including tablets or capsules, coatings,
sachets, and suspensions, and in effervescent tablets. It can also be
used in direct compression and wet granulation.
In buccal applications such as chewable tablets it is commonly
used because of its negligible negative heat of solution, mild
sweetness, and ‘mouth feel’. It is also used widely in lozenges,
sugar-free chewing gum, and hard-boiled candies, and as a
sweetening agent in confectionery for diabetics.
Безопасность
Isomalt is used in oral pharmaceutical formulations, confectionery,
and food products. It is generally regarded as a nontoxic,
nonallergenic, and nonirritant material.
Toxicological and metabolic studies on isomalt have been
summarized in a WHO report prepared by the FAO/WHO Expert
Committee (JECFA), resulting in an acceptable daily intake of ‘not
specified’.
The glycosidic linkage between the mannitol or sorbitol moiety
and the glucose moiety is very stable, limiting the hydrolysis and
absorption of isomalt in the small intestine. There is no significant
increase in the blood glucose level after oral intake, and glycemic
response is very low, making isomalt suitable for diabetics. The
majority of isomalt is fermented in the large intestine. In general,
isomalt is tolerated very well, although excessive consumption may
result in laxative effects.
Isomalt is not fermented by bacteria present in the mouth;
therefore no significant amount of organic acid is produced that
attacks tooth enamel.
хранилище
Isomalt has very good thermal and chemical stability. When it is
melted, no changes in the molecular structure are observed. It exhibits considerable resistance to acids and microbial influences.
Isomalt is non-hygroscopic, and at 25°C does not significantly
absorb additional water up to a relative humidity (RH) of 85%;
paracetamol (acetaminophen) tablets based on isomalt were stored
for 6 months at 85% RH at 20°C and retained their physical
aspect.
If stored under normal ambient conditions, isomalt is chemically
stable for many years. When it is stored in an unopened container at
20°C and 60% RH, a re-evaluation after 3 years is recommended.
Регуляторный статус
GRAS listed. Accepted as a food additive in Europe.
изомальт препаратная продукция и сырье
сырьё
препарат