By J. STEINER, F.C.S.
Rice contains much more starch, but on the other hand, much less
albuminous matter and ash, than maize and barley. The compositions of
different kinds of dried rice do not vary very much, but as the amount
of moisture in the raw grain ranges from 5 to 15 per cent., no brewer
ought to buy rice without having first of all inquired with the
assistance of a chemist as to the percentage of water present in the
sample.
Another point requiring attention is that of taking notice of the
acidity, which also varies a good deal for different sorts of rice. In
comparing the nutritive values of the three kinds of grain before us,
Pillitz obtained the following numbers:
Barley. Maize. Rice.
-------------- ------------- ------------------
Air Dried at Air Dried at Air Dried at With
Dry. 100° C. Dry. 100° C. Dry. 100° C. Husk.
Moisture. 13.88 --- 13.89 --- 12.51 --- 12.00
Starch. 54.07 62.65 62.69 73.27 74.88 85.41 74.50
Dextrin and
sugar. 5.66 6.67 3.57 4.14 1.12 1.26 ---
Total albumen
matter. 14.00 16.28 10.63 12.35 9.19 10.40 7.80
Mineral matter. 2.33 2.70 1.48 1.71 0.84 0.94 2.30
Fatty matter. 2.30 2.68 4.36 5.03 0.78 0.88 0.30
Cellulose
matter. 7.76 9.02 3.38 4.50 0.68 1.11 3.10
-----------------------------------------------------------
100.00 100.00 100.00 100.00 100.00 100.00 100.00
On looking over this table, we notice that rice contains by about 20 per
cent, more starch than barley, and by about 10 to 12 per cent, more than
maize.
But on the other hand, barley and maize are richer in albuminous matter
and in ash. The extractive matter, _i. e._, the part which is soluble in
cold water, is also much greater in barley and maize than in rice. The
extractive matter is for barley 8.7 per cent., for maize 6.3 per cent.,
while rice contains only 2.1 per cent., and it consists in each case of
dextrin, sugar, the soluble part of the ash, and of some nitrogenous
matter (soluble albumen).
The amount of woody fiber or cellulose is considerable for rice with its
husk, but only slight for samples without husk. The seat of the mineral
matter of the grain of rice is mainly in the husk, and as this ash is
very valuable as nourishment for the yeast plant, it is an open question
whether it would not be preferable to use for brewing purposes rice with
its husk. The comparatively largest amount of fat is contained in
maize; and as such oil is not desirable for brewing purposes, different
recommendations have been advanced for freeing the grain from it. In the
following table some of the mineral constituents of the three kinds of
grain are compared with each other. These data refer to 100 parts of
ash, and are taken from analysis given by Dr. Emil Wolf.
100 parts of
Potash Lime Magnesia Phosphoric Silica grain contain
acid ash.
Barley. 21.9 2.5 8.3 32.8 27.2 2.55 p. ct.
Rice with
husk. 18.4 5.1 8.6 47.2 0.6 7.84 "
Rice without
husk. 23.3 2.9 13.4 51.0 3.0 0.39 "
Maize. 27.0 2.7 14.6 44.7 2.2 1.42 "
The excessive amount of ash in rice with its husk is very remarkable,
and as this mineral matter consists to a great extent of phosphoric acid
and potash, the larger part of it is soluble in water. Consequently
on using rice with its husk for brewing purposes, the yeast will be
provided with a considerable amount of nutritive substance.
In conclusion it need hardly be mentioned that the use of rice with its
husk would also be of considerable pecuniary advantage. There is very
little oil in the husk of rice, as shown above by analysis, and it is
not likely that the flavor of the brew would suffer by it.--_London
Brewers' Journal._
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