Carrageenan Chemische Eigenschaften,Einsatz,Produktion Methoden
Chemische Eigenschaften
Carrageenan, when extracted from the appropriate seaweed source,
is a yellow-brown to white colored, coarse to fine powder that is
odorless and tasteless.
Occurrence
Irish moss is a seaweed found in Europe and on the coasts of Canada.
Verwenden
Carrageenan is a gum that is a seaweed extract obtained from red
seaweed chondrus crispus (also known as irish moss), gigartina, and
eucheuma species. chondrus crispus yields kappa and lambda carra-
geenans. gigartina yields kappa and lambda carrageenans. eucheuma
yields kappa and iota carrageenans. it exists as various salts or mixed
salts of a sulfate ester. it is classified mainly as kappa, iota, and
lambda types which differ in solubility and gelling properties. the
kappa and iota types require hot water (above 71°c) for complete
solubility and can form thermally reversible gels in the presence of
potassium and calcium cations, respectively. the kappa gels are brit-
tle with syneresis while the iota gels are more elastic without synere-
sis. the lambda type is cold-water soluble and does not form gels.
kappa and iota carrageenan are very reactive with milk protein
products. carrageenan is used to stabilize milk protein at 0.01–0.05%
and to form water gels at 0.5–1.0%. its uses include dairy products,
water gel desserts, and low-calorie jellies. a typical use level in water
systems is 0.2–1.0% and milk systems is 0.01–0.25%. also termed
chondrus extract.
Definition
A sulfur phycocolloid: the aqueous, usually gel-
forming, cell-wall polysaccharide mucilage found
in red algae (Chondrus crispus and several other
species). It is water-extracted from a seaweed called
carrageen or Irish moss (east coast of southern
Canada, New England, and south to New Jersey). It
is a mixture of polysaccharide fractions: (1) The λ
fraction is cold-water soluble, contains d-galactose
and 35% esterified sulfate, and does not gel. (2) The
κ fraction contains d-galactose and 3,6-anhydro-d-
galactose (1.4:1 ratio) and 25% esterified sulfate.
The κ form does not gel without addition of a solute;
the properties of the gel depend on the amount and
nature of the added solute. Another species of sea-
weed produces 100% κ from North Carolina to the
tropics. Carrageenan is a hydrophilic colloid that
absorbs water readily and complexes with milk pro-
teins.
Allgemeine Beschreibung
Carrageenans are mucopolysaccharides from the cell walls of the red algae. They are anionic linear polymers composed of 1,3α-1,4β-galactans having one (κ-), two (ι-) or three (λ-) sulfates per disaccharide unit. In ionic solutions, κ- and ι-carrageenans self-associate into helical structures that form rigid or flexible gels, respectively. λ-carrageenans do not form helices and are non-gelling. Carrageenans are used commercially as thickeners and stabilizing agents.
Hazard
Questionable carcinogen.
Landwirtschaftliche Anwendung
Carrageenans are naturally occurring hydrophilic
colloids found in various species of red seaweeds.
They perform a role similar to cellulose in terrestrial
plants.
Carrageenans are a highly sulphated galactan. Due
to this they are a strongly anionic polymer which makes
them useful commercially. They are commercially
extracted for their use as water soluble gums.
Carrageenans may be compared with furcellaran
extracted from agars (furcellarans have a smaller
proportion of half-ester sulphate). Agars, in contrast, are
commonly considered non-ionic
Sicherheitsprofil
Poison by intravenous
route. Questionable carcinogen with
experimental neoplastigenic and tumorigenic
data. When heated to decomposition it
emits acrid smoke and fumes.
Sicherheit(Safety)
Carrageenan is widely used in numerous food applications and is
increasingly being used in pharmaceutical formulations. Carrageenan
is generally regarded as a relatively nontoxic and nonirritating
material when used in nonparenteral pharmaceutical formulations.
However, carrageenan is known to induce inflammatory
responses in laboratory animals, and for this reason it is frequently
used in experiments for the investigation of anti-inflammatory
drugs. Animal studies suggest that degraded carrageenan
(which is not approved for use in food products) may be associated
with cancer in the intestinal tract, although comparable evidence
does not exist in humans.
The WHO has set an acceptable daily intake of carrageenan of
‘not specified’ as the total daily intake was not considered to
represent a hazard to health. In the UK, the Food Advisory
Committee has recommended that carrageenan should not be used
as an additive for infant formulas.
LD
50 (rat, oral): >5 g/kg
LD
50 (rabbit, skin): >2 g/kg/4 h
LC
50 (rat, inhalation): >0.93 mg/L
Lager
Carrageenan is a stable, though hygroscopic, polysaccharide and
should be stored in a cool, dry place.
Carrageenan in solution has maximum stability at pH 9 and
should not be heat processed at pH values below 3.5. Acid and
oxidizing agents may hydrolyze carrageenan in solution leading to
loss of physical properties through cleavage of glycosidic bonds.
Acid hydrolysis depends on pH, temperature and time. The acid
hydrolysis takes place only when the carrageenan is dissolved, and
the hydrolysis is accelerated as the processing temperature and/or
the processing time is increased. However, when the carrageenan is
in its gelled state the acid hydrolysis no longer takes place.
läuterung methode
This D-galactose-anhydro-D or Lgalactoside polysaccharide is precipitated from 4g of Carrageenan in 600mL of water containing 12g of KOAc by addition of EtOH. Collect the fraction that precipitates between 30 and 45% (v/v) of EtOH and dry them in vacuo. [Pal & Schubert J Am Chem Soc 84 4384 1962.]
Inkompatibilitäten
Carrageenan can react with cationic materials. If complexation of
cationic materials, with associated modification of the active
compound’s solubility, is undesirable, the use of carrageenan is
not recommended.
Carrageenan may interact with other charged macromolecules,
e.g. proteins, to give various effects such as viscosity increase, gel
formation, stabilization or precipitation.
Regulatory Status
GRAS listed. Accepted as a food additive in Europe. Included in the
FDA Inactive Ingredients Database (dental; oral capsules, granules,
powders and syrups; topical; transdermal preparations; and
controlled-release film preparations). Included in the Canadian
List of Acceptable Non-medicinal Ingredients. Included in nonparenteral
medicines (oral granules, capsules (shells), and orodispersible
tablets) licensed in the UK.
Carrageenan Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
