View Full Version : Maple Seeds

05-09-2009, 02:34 PM
It's that time of year (here anyway) when maple seeds are falling by the thousands. I have a two part question for you.

1. Can anyone reference a reliable source that says they are edible? None of my books say you can eat them.
2. Does anyone collect them and eat them?

05-09-2009, 03:55 PM


(From the Chemical Laboratory, New York Agricultural Experiment Station, Geneva.)

(Received for publication, April 22, 1918.)


The food shortage in various European countries has necessitated not only careful conservation of available food supplies but
also has compelled the utilization of many plant constituents not ordinarily classed as foodstuffs. A similar condition is impending
in this country. In order to conserve our stores of food products the exercise of the greatest economy will be necessary.

In this connection it might be pointed out that numerous plant products not previously. considered as food might be used to
replace, in part at least, many of the more expensive and essential articles of food and thus aid in conservation.

The object of this paper is to call attention to one such substance possessing high food value which has not been utilized
heretofore. We refer to .the seed of the silver maple (Acer sacchar & urn). So far as we are aware this product has not been either used or analyzed previously; at least there is no record in the chemical literature of any earlier analysis. We have, therefore, undertaken an investigation of the constituents of this seed.

Silver maple is thickly planted in many parts of the country for shade and ornamental purposes.

The trees are prolific producers of seeds which mature and fall early in the summer; about the middle of June in Western New York. The seeds can be easily harvested by raking them off the ground because they are usually carried only a short distance by the wind.

The seed or samara consists of two principal parts;

(1) the winged pericarp, and (2), the seed surrounded by a brown seed coat or testa. The seed, after removal of the pericarp and testa, consists of two green-colored cotyledons, separated by a thin white membrane. When dry, the wing or pericarp is brittle and can be easily separated from the seed. The testa is a very thin, brown-colored, brittle membrane which can be removed from the seed by scrubbing.

The investigation is incomplete. We have been unable to make any digestibility experiments and are therefore unable to
state the nutritional value of the globulin. An organic phosphorus compound has been isolated. This substance appears to
be very similar to if not identical with phytin. A globulin has also been separated in pure form but it has not been analyzed.
Certain other soluble constituents require further study. The completion of the investigation has been indefinitely postponed
by the war. It seems advisable, however, to publish this preliminary analysis at this time and to call attention to the food
value of maple seed.


The ripe samaras were picked by hand, allowed to dry in the air for several days, and then dried in a current of air at a temperature of 40 or 50” until of constant weight. The seeds were then separated from the wings or pericarp. The loss in weight on drying, was 55.34 per cent. Of the dry samara, the seed or cotyledons represented 70.00 per cent and the wings 30.00 per cent.

The outer brown seed coat was removed by rubbing the seeds together in a cloth bag and sifting through a coarse sieve. The
percentage of the seed coat or testa could not be determined because the plumule and other small particles of the cotyledons
broke off in the process of rubbing and became mixed with the testa.

05-09-2009, 03:56 PM
The cotyledons, separated and prepared as described above,were powdered and analyzed. They had the following composition,
calculated to the water-free basis.

per cent
Starch............................................ ........ 41.94
Protein (N X 6.25). . . . . . . . . . . . . . . . . . . 27.50
Sucrose........................................... ........ 15.78
Pentosans......................................... ........ 4.07
Galactan.......................................... ........ 1.08
Crude fiber.. . . . . . . . . . . . . . . . . . . . . . . . 2.36
Crude fat.. . . . . . . . . . . . . . . . . . . . . . . . . .3.55
Ash. . . . . . . . “ “ “ . . ‘ . . . . . . . . . . . ......... 5.01

The soluble constituents of the seed were separated as follows:

1. The powdered seed was extracted with ether which removed practically all of the green color in addition to the fat. A thick green-colored oil was obtained on evaporating the ether. This oil contained a volatile substance which possessed an extremely pungent odor. It is our intention to isolate and study this substance as soon as possible.

2. After the ether had evaporated, the seed residue was extracted with 70 per cent alcohol. This extract contained from 16 to 17 per cent of solids. It contained no weighable quantity of invert sugar but after inversion it strongly reduced Fehling’s solution. Estimated by this method, the sugar was equal to 15.78 per cent of sucrose. In order to confirm the presence of sucrose in the extract, the sugar was isolated in pure form and twice recrystallized from alcohol and water. , Judging by its properties and specific rotation, this substance was undoubtedly pure sucrose.

3. After extracting with 70 per cent alcohol, the seed residue was dried in vacuum over sulfuric acid. It was then extracted with 5 per cent sodium chloride solution to which sufficient barium hydroxide had been added to maintain a neutral reaction. The dissolved globulin was precipitated by ammonium sulfate. It was freed as much as possible from the mother liquor by the centrifuge, dissolved by adding a little water, filtered, and the solution dialyzed. The globulin which separated was suspended in
water and dissolved by adding a little ammonium sulfate, the solution filtered, and again precipitated with ammonium sulfate to & saturation. It was then centrifugalized, the precipitate dissolved in water, filtered, and again dialyzed. After filtering, dehydrating with alcohol, and drying over sulfuric acid in vacuum the substance was obtained as a nearly white heavy powder. The globulin showed no crystalline structure. Under the microscope it appeared to consist of small uniform globules. This globulin will be more fully studied and described in a subsequent publication.

4. The residue, after extracting with the dilute salt solution, was extracted with 2 per cent hydrochloric acid for the purpose of removing the soluble phosphorus compounds. The organic phosphorus compound in the extract was purified by repeated alternate precipitation, with barium hydroxide and alcohol, from dilute hydrochloric acid solution. It was finally obtained as a pure white barium salt. Lack of time has prevented the identification of this substance. In reaction and appearance, however,
it seems to be very similar to the barium salt of inosite hexaphosphoric acid or phytin. We hope to study this substance more fully and will report upon it in a later publication.

Distribution of the Phosphorus.

The total phosphorus, as determined in the ash and by the Neumann method, was the same. The total soluble and the inorganic
phosphorus were determined in 2 per cent hydrochloric acid extracts of the powdered seed. The time of extraction was
3 hours. The organic phosphorus is the difference between the inorganic and the total soluble phosphorus.


Attention is called to the high food value of the seed of the silver maple. The analysis shows that the chief constituents are
starch, protein, and sucrose. The principal protein is a globulin. The ash contains much potassium and phosphorus. In the seed,
the phosphorus is present chiefly in organic combination.

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05-09-2009, 04:17 PM
The flowers of some maples are edible, too:


05-09-2009, 04:26 PM
Thanks! I may have to go chomp on some.