N.F. � IRISH MOSS � CARRAGEEN
Monograph of the U.S.D. 1926
Compiled and edited by
N. F. CHONDRUS Chondr. [Irish Moss,
"Chondrus is the dried bleached plant of Chondrus
Crispus (Linne) Stackhouse or of Gigartina
et Woodard) J. Agardh (Fam. Gigartinaceae).
Chondrus contains not more than 2 per cent of foreign organic
matter." N. F.
Crispus, Pigwrack, Killeen, Pearl Moss; Hen's Dulse;
Fr. Cod.; Mousse Marine perlee, Fr.;
Carrageen, P. G.; Irlandisches Moos, Perlmoos,
Knorpeltang, G.; Fuco
carageo, Musco d'lrlanda,
Fuco crispo. It.; Caragaen,
Musgo marino perlado,
Chondrus crispus grows upon rocks and stones on the coast of
and is especially abundant on the southern and western coasts of
where it is collected. It is also a native of the
, and is gathered largely
on the coast of
where it is partly torn from the rocks and partly collected from the
beach, on which it is thrown up during storms. It is prepared for market
by spreading it out to dry and bleach in the sun. For elaborate accounts
of the plant, of its distribution on the sea coast of Massachusetts, and
of the mode of gathering and curing, see A. J. P., 1895, 596; 1899, 483.
Kraemer witnessed the methods pursued on the
coast in the collection of Irish moss at
which appears to be a particularly favorable situation. The season for
collection begins late in May and continues to September, June and July
being the best months. The moss at present is only found on rocks that are
from 15 to 20 feet below the tide, hence women no longer engage in its
collection. The men go out in their sail boats or dories at half tide,
come in at half flood. With their long rakes they scrape the moss off the
rocks, collecting thus about 50 pounds to the boat, the total for the
being about 10,000 pounds. The moss is spread out on the high beach for a
week or so, the action of the sun and dew bleaching it. It is then
enclosed in hogsheads, in which it is again saturated with sea water by
rolling them in the marshes; after which it is again spread out and
subjected to the bleaching process, this alternate treatment being
repeated four or five times, until the product is of a yellowish or white
color. The final drying is done in barns, where the moss is stored until
it is packed in 100 lb. barrels at the end of the season.
In the course of this journey he had opportunity to observe the Chondrus
growing and gathered in different localities along the coast, and found it
to consist chiefly, if not entirely, of Chondrus crispus. While it is
stated in Dr. Farlow's
" The Marine Algae of New England" that the closely
resembling Gigartina mamillosa is common from Boston northward, Kraemer is
inclined to believe that Chondrus crispus (L.) Lyngbye,
is practically the only source of the American drug. (See Proc. Perm.
Pharm. Assoc., 1899, 113-116.) Tunmann (Apoth.
Zeit., 1909, pp. 91 and 151) has given an
elaborate account of the morphology and composition of Chondrus. Gigartina
mamillosa Ag. resembles the true Irish
moss, and, growing with it upon the rocks, may be gathered with it. It
can, however, be at once distinguished by the numerous papillae which
cover the surface and margins of the fronds and bear the fruit
(cystocarps). In chemical and medicinal properties it is probably
identical with C. crispus.
The commercial supplies of Chondrus are chiefly obtained from
Irish moss when collected is washed and dried. It is probably
sometimes bleached by the use of potassium permanganate and sodium
thiosulphate by the same process as that used for bleaching sponge. Schack
was led to suspect this through discovering the presence of sulphurous
acid in a German specimen. (Ph. 'Ztg., 1886, p. 87.)
The presence of arsenic has been determined in some commercial lots, being
caused, no doubt, by the impurities in the sulphur used for bleaching
Chondrus. Some " faked " samples have
yielded as much as 35 per cent, of ash which contained a large quantity of
calcium sulphate. The gelatinizing value of specimens of this kind is
about 60 per cent, below normal. In the fresh state it is of a purplish
color, but as found in the shops, is yellowish or yellowish-white, with
occasionally purplish portions.
and Physical Properties. � "
Whole Chondrus. � Entire plants matted together, consisting of a
slender stalk from which arises a series of dichotomously branching, more
or less flattened segments, emarginate or deeply cleft at the tips; from 5
to 15 cm. in length, and 1 to 10 mm. in width; yellowish-white;
translucent, frequently coated with a calcareous deposit which effervesces
with hydrochloric acid; sometimes with fruit bodies or sporangia embedded
near the apex of the segments (in C. crispus) or with sporangia borne on
short tuberculated projections or stalks, more or less scattered over the
upper portion of the segments (in G. mamillosa); somewhat cartilaginous. Odor
slight, seaweed-like; taste mucilaginous, saline.
Boil one part of Chondrus for about ten minutes with 30 parts of water,
replacing the water lost by evaporation; the strained liquid forms a thick
jelly upon cooling. When softened in cold water, Chondrus becomes
gelatinous and transparent, the thallus remaining nearly smooth and
uniform and not swollen except slightly at the tips; a solution made by
boiling 0.3 Gm. of the drug in 100 cc. of water and filtering gives no
precipitate on the addition of tannic acid T.S. (absence of gelatin), and
when cold does not give a blue color on the addition of iodine T.S.
(absence of starch)." N. F. It swells in cold water, but does not
dissolve. Boiling water dissolves a large proportion of it, and the
solution, if sufficiently concentrated, gelatinizes on cooling. Herberger
found 79 per cent, of a mucilaginous substance
resembling pectin, and 9.5 of mucus, with fatty matter, free acids,
This gum-like substance, which is known as carrageenin, is distinguished from acacia by affording, when dissolved in water, no precipitate with
alcohol; from starch, by not becoming blue with tincture of iodine; from
pectin, by yielding no precipitate with lead acetate and from mucic acid
by the action of nitric acid. It is probably not a pure principle but a
mixture of carbohydrate derivatives. According to Sebor
(1900) it yields, when hydrolyzed, galactose, dextrose, levulose and salts
of sulphuric acid. Muther and Tollens
(1904) found also hydroxy-methylfurfuraldehyde. Blondeau
in 1865 prepared a substance which he called goemine by boiling chondrus
for several hours and precipitating the resulting mucilage with alcohol. Fucusol
is an oily liquid, isomeric with furfural, which is obtained by boiling
the seaweed with dilute sulphuric acid.
Carrageenin has been used as a substitute for acacia under the name of "
gum Arabic "; it occurs in three forms, white, pale yellow and
yellow. These differ from the true acacia not only in chemical properties,
but in being much less adhesive (Federer, Ph.
Era, 1887). The ash of chondrus amounts to from 8 to 15 per cent, and contains
traces of iodine. On oxidation with nitric acid the dry moss yields from
21.6 to 22.2 per cent, of mucic acid. There is present also about 7 per
cent, of protein material. The mucilage of Irish moss has come into
considerable use as an emulsifying agent. (Proc. A.
Ph. A., 1887; A. J. P., 1888, 170.)
� Chondrus is nutritive, and, being easy of digestion and not unpleasant
to the taste, forms a useful article of diet in cases in which the
farinaceous preparations, such as tapioca, sago, barley, etc., are usually
employed. It was formerly employed as a demulcent in chronic pectoral
affections, diarrhea, and disorders of the kidneys and bladder, but is
rarely so employed to-day. It may be used in the form of decoction, made
by boiling a pint and a half of water with half an ounce of the moss down
to a pint. Sugar and lemon juice may usually be added to improve the
flavor. It is recommended to macerate the moss for about ten minutes in
cold water before submitting it to decoction; any unpleasant flavor that
it may have acquired from the contact with foreign substances is thus
four drachms (15.5 Gm.).
Off. Prep.Mucilago Chondri,
See Also .. Demulcents.Veg.
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