THE COMPOSITION AND FOOD VALUE OF COCOA AND CHOCOLATE
Before the Spaniards made themselves Masters of Mexico, no
other drink was esteem'd but that of cocoa; none caring for
wine, notwithstanding the soil produces vines everywhere in
great abundance of itself.
John Ogilvy's _America_, 1671.
The early writers on chocolate generally became lyrical when they wrote
of its value as a food. Thus in the _Natural History of Chocolate_, by
R. Brookes (1730), we read that an ounce of chocolate contains as much
nourishment as a pound of beef, that a woman and a child, and even a
councillor, lived on chocolate alone for a long period, and further:
"Before chocolate was known in Europe, good old wine was called the milk
of old men; but this title is now applied with greater reason to
chocolate, since its use has become so common, that it has been
perceived that chocolate is, with respect to them, what milk is to
infants."
A more temperate tone is shown in the following, from _A Curious
Treatise of the Nature and Quality of Chocolate_, by Antonio Colmenero
de Ledesma, a Spaniard, Physician and Chyrurgion of the city of Ecija,
in Andaluzia (printed at the Green Dragon, 1685):
So great is the number of those persons, who at present do
drink of Chocolate, that not only in the West Indies, whence
this drink has its original and beginning, but also in
Spain, Italy, Flanders, &c., it is very much used, and
especially in the Court of the King of Spain; where the great
ladies drink it in a morning before they rise out of their
beds, and lately much used in England, as Diet and Phisick
with the Gentry. Yet there are several persons that stand in
doubt both of the hurt and of the benefit, which proceeds
from the use thereof; some saying, that it obstructs and
causes opilations, others and those the most part, that it
fattens, several assure us that it fortifies the stomach:
some again that it heats and inflames the body. But very many
steadfastly affirm, that tho' they shou'd drink it at all
hours, and that even in the Dog-days, they find themselves
very well after it.
So much for the old valuations; let us now attempt by modern methods to
estimate the food value of cacao and its preparations.
_Food Value of Cacao Beans._
In estimating the worth of a food, it is usual to compare the fuel
values. This peculiar method is adopted because the most important
requirement in nutrition is that of giving energy for the work of the
body, and a food may be thought of as being burnt up (oxidised) in the
human machine in the production of heat and energy. The various food
constituents serve in varying degrees as fuel to produce energy, and
hence to judge of the food value it is necessary to know the chemical
composition. Below we give the average composition of cacao beans and
the fuel value calculated from these figures:
AVERAGE COMPOSITION AND FUEL VALUE OF FRESHLY ROASTED CACAO BEANS
(NIBS).
_Composition._ _Energy-giving power_
_Calories per lb._
Cacao Butter 54.0 = 2,282
Protein (total nitrogen 2.3%) 11.9 = 221
Cacao Starch 6.7 } = 472
Other Digestible Carbohydrates, etc. 18.7 }
Stimulants { Theobromine 1.0
{ Caffein 0.4
Mineral Matter 3.2
Crude Fibre 2.6
Moisture 1.5
------ -----
100.0 2,975
------ -----
[Illustration: COCOA AND CHOCOLATE DESPATCH DECK AT BOURNVILLE.]
It will be seen from the above analysis that the cacao bean is rich in
fats, carbohydrates and protein, and that it contains small quantities
of the two stimulants, theobromine and caffein. In the whole range of
animal and vegetable foodstuffs there are only one or two which exceed
it in energy-giving power. If expressed in quite another way, namely, as
"food units," the value of the cacao bean stands equally high, as is
shown by the following figures taken from Smetham's result published in
the Journal of the Royal Agricultural Society, 1914:
"FOOD UNITS."
Turnips 8
Carrots 12
Potatoes 26
Rice 102
Corn Flour 104
Wheat 106
Peas 113
Oatmeal 117
Coconut 159
Cacao Bean 183
These figures indicate the high food value of the raw material; we will
now proceed to consider the various products which are obtained from
it.
_Food Value of Cocoa._
AVERAGE COMPOSITION AND FUEL VALUE OF UNTREATED COCOA.
_Composition._ _Energy-giving power_
_Calories per lb._
Cacao Butter 28.0 = 1,183
Protein 18.3 = 340
Cacao Starch 10.2 } = 718
Other Digestible Carbohydrates, etc. 28.4 }
Stimulants {Theobromine 1.5
{Caffein 0.6
Mineral Matter 5.0
Crude Fibre 4.0
Moisture 4.0
----- -----
100.0 2,241
----- -----
("Soluble" Cocoa, _i.e._, cocoa which has been treated with alkaline
salts, is almost identical in composition, save that the mineral matter
is about 7.5 per cent.).
As cocoa consists of the cacao bean with some of the butter extracted--a
process which increases the percentage of the nitrogenous and
carbohydrate constituents--it will be evident that the food value of
cocoa powder is high, and that it is a concentrated foodstuff. In this
respect it differs from tea and coffee, which have practically no food
value; each of them, however, have special qualities of their own. Some
of the claims made for these beverages are a little remarkable. The
Embassy of the United Provinces in their address to the Emperor of China
(Leyden, 1655), in mentioning the good properties of tea, wrote: "More
especially it disintoxicates those that are fuddl'd, giving them new
forces, and enabling them to go to it again." The Embassy do not state
whether they speak from personal experience, but their admiration for
tea is undoubted. Tea, coffee, and cocoa are amongst our blessings, each
has its devotees, each has its peculiar delight: tea makes for
cheerfulness, coffee makes for wit and wakefulness, and cocoa relieves
the fatigued, and gives a comfortable feeling of satisfaction and
stability. Of these three drinks cocoa alone can be considered as a
food, and just as there are people whose digestion is deranged by tea,
and some who sleep not a wink after drinking coffee, so there are some
who find cocoa too feeding, especially in the summer-time. These
sufferers from biliousness will think it curious that cocoa is
habitually drunk in many hot climates, thus, in Spanish-speaking
countries, it is the custom for the priest, after saying mass, to take a
cup of chocolate. The pure cocoa powder is, as we saw above, a very rich
foodstuff, but it must always be remembered that in a pint of cocoa only
a small quantity, about half an ounce, is usually taken. In this
connection the following comparison between tea, coffee and cocoa is not
without interest. It is taken from the _Farmer's Bulletin_ 249, an
official publication of the United States Department of Agriculture:
COMPARISON OF ENERGY-GIVING POWER OF A PINT OF TEA, COFFEE AND COCOA.
Fuel value
Kind of Beverage Water Protein Fat Carbohydrates per lb.
--------------------------------------------------------------------------
% % % % Calories
_Tea_
(0.5 oz. to 1 pt. water) 99.5 0.2 0 0.6 15
_Coffee_
(1 oz. to 1 pt. water) 98.9 0.2 0 0.7 16
_Cocoa_
(0.5 oz. to 1 pt. water) 97.1 0.6 0.9 1.1 65
These figures place cocoa, as a food, head and shoulders above tea and
coffee. The figures are for the beverages made without the addition of
milk and sugar, both of which are almost invariably present. A pint of
cocoa made with one-third milk, half an ounce of cocoa, and one ounce of
sugar would have a fuel value of 320 calories, and is therefore
equivalent in energy-giving power to a quarter of a pound of beef or
four eggs.
Cocoa is stimulating, but its action is not so marked as that of tea or
coffee, and hence it is more suitable for young children. Dr. Hutchison,
an authority on dietetics, writes: "Tea and coffee are also harmful to
the susceptible nervous system of the child, but cocoa, made with plenty
of milk, may be allowed, though it should be regarded, like milk, as a
food rather than a beverage properly so called."
_How to Make a Cup of Cocoa._
Tea, coffee and cocoa are all so easy to make that it is remarkable
anyone should fail to prepare them perfectly. Whilst in France everyone
can prepare coffee to perfection, and many fail in making a cup of tea,
in England all are adepts in the art of tea-making, and many do not
distinguish themselves in the preparation of coffee. Cocoa in either
country is not always the delightful beverage it should be. The
directions below, if carefully followed, will be found to give the
character of cocoa its full expression. The principal conditions to
observe are to avoid iron saucepans, to use boiling water or milk, to
froth the cocoa before serving, and to serve steaming hot in thick cups.
[Illustration]
The amount of cocoa required for two large breakfast cups, that is one
pint, is as much as will go, when piled up, in a dessert spoon. Take
then a heaped dessert-spoonful of pure cocoa and mix dry with one and a
half times its bulk of fine sugar. Set this on one side whilst the
boiling liquid is prepared. Mix one breakfast cup of water with one
breakfast cup of milk, and raise to the boil in an enamelled saucepan.
Whilst this is proceeding, warm the jug which is to hold the cocoa, and
transfer the dry sugar-cocoa mixture to it. Now pour in the boiling
milk and water. Transfer back to saucepan and _boil_ for one minute.
Whisk vigorously for a quarter of a minute. Serve without delay.
_Digestibility of Cocoa._
We have noted above the high percentage of nutrients which cocoa
contains, and the research conducted by J. Forster[1] shows that these
nutrients are easily assimilated. Forster found that the fatty and
mineral constituents of cocoa are both _completely_ digested, and the
nitrogenous constituents are digested in the same proportion as in
finest bread, and more completely than in bread of average quality. One
very striking fact was revealed by his researches, namely, that the
consumption of cocoa increases the digestive power for other foods which
are taken at the same time, and that this increase is particularly
evident with milk. Dr. R.O. Neumann[2] (who fed himself with cocoa
preparations for over twelve weeks), whilst not agreeing with this
conclusion, states that: "The consumption of cocoa from the point of
view of health leaves nothing to be desired. The taking of large or
small quantities of cocoa, either rich or poor in fat, with or without
other food, gave rise to no digestive troubles during the 86 days which
formed the duration of the experiments." He considers that cocoas
containing a high percentage of cacao butter are preferable to those
which contain low percentages, and that a 30 per cent. butter content
meets all requirements. It is worthy of note that 28 to 30 per cent. is
the quantity of butter found in ordinary high-class cocoas.
[1] _Hygienische Rundschau_, 1900, p. 305.
[2] _Die Bewertung des Kakaos als Nahrungs- und Genussmittel_,
1906.
As experts are liable to disagree, and it is almost possible to prove
anything by a judicious selection from their writings, it may be well to
give an extract from some modern text book as more nearly expressing the
standard opinion of the times. In _Second Stage Hygiene_, by Mr. Ikin
and Dr. Lyster, a text book written for the Board of Education Syllabus,
we read, p. 96: "... in the better cocoas the greater part of the fat is
removed by heat and pressure. In this form cocoa may be looked upon as
almost an ideal food, as it contains proteids, fats, and carbohydrates
in roughly the right proportions. Prepared with milk and sugar it forms
a highly nutritious and valuable stimulating beverage."
_Stimulating Property of Cocoa._
The mild stimulating property which cocoa possesses is due to the
presence of the two substances, theobromine and caffein. The presence of
theobromine is peculiar to cocoa, but caffein is a stimulating principle
which also occurs in tea and coffee. Whilst in the quantities in which
they are present in cocoa (about 1.5 per cent. of theobromine and 0.6
per cent. of caffein) they act only as agreeable stimulants, in the pure
condition, as white crystalline powders, they are powerful curative
agents. Caffein is well known as a specific for nervous headaches, and
as a heart stimulant and diuretic. Theobromine is similar in action, but
has the advantage for certain cases, that it has much less effect on the
central nervous system, and for this reason it is a very valuable
medicine for sufferers from heart dropsy, and as a tonic for senile
heart. That its medicinal properties are appreciated is shown by its
price: during 1918 the retail price was about 8 shillings an ounce, from
which we can calculate that every pound of cocoa contained nearly two
shillingsworth of theobromine.
_"Soluble" Cocoa._
Whilst Forster states that treated cocoa is the most digestible, experts
are not in agreement as to which is the more valuable foodstuff, the
pure untouched cocoa, or that which is treated during its manufacture
with alkaline salts. The cocoa so treated is generally described as
"soluble," although its only claim to this name is that the mineral
salts in the cocoa are rendered more soluble by the treatment. It is
also sometimes incorrectly described as containing alkali, but actually
no alkali is present in the cocoa either in a free state or as
carbonate; the potassium exists "in the form of phosphates or
combinations of organic acids, that is to say, in the ideal form in
which these bodies occur in foods of animal and vegetable origin"
(Fritsch, _Fabrication du Chocolat_, p. 216).
[Illustration: BOXING CHOCOLATES.]
_Food Value of Chocolate._
I ate a little chocolate from my supply, well knowing the
miraculous sustaining powers of the simple little block (from
_Mr. Isaacs_, by F. Marion Crawford).
Whilst the food value of cocoa powder is very high the drink prepared
from it can only be regarded as an accessory food, because it is usual
to take the powder in small quantities--just as with beef-tea it is
usual to take only a small portion of an ox in a tea-cup--but chocolate
is often eaten in considerable quantities at a time, and must therefore
be regarded as an important foodstuff, and not considered, as it
frequently is considered, simply as a luxury.
The eating of cacao mixed with sugar dates from very early days, but it
is only in recent times that it has become the principal sweetmeat. What
would a "sweetshop" be to-day without chocolate, that summit of the
confectioner's art, when the rich brown of chocolate is the predominant
note in every confectioner's window? What would the lovers in England do
without chocolates, which enable them to indulge their delight in giving
that which is sure to be well received?
As a luxury it is universally appreciated, and because of this
appreciation its value as a food is sometimes overlooked.
During the war chocolate was valued as a compact foodstuff, which is
easily preserved. Dr. Gastineau Earle, lecturing for the Institute of
Hygiene in 1915 on "Food Factor in War," said: "Chocolate is a most
valuable concentrated food, especially when other foods are not
available; it is the chief constituent of the emergency ration." Its
importance as a concentrated foodstuff was appreciated in the United
States, for every "comfort kit" made up for the American soldiers
fighting in the war contained a cake of sweet chocolate.
There are a number of records of people whose lives have been preserved
by means of chocolate. One of the most recent was the case of Commander
Stewart, who was torpedoed in H.M.S. "Cornwallis" in the Mediterranean
in 1917. He happened to have in his cabin one of the boxes of chocolate
presented to the Army and Navy in 1915 by the colonies of Trinidad,
Grenada, and St. Lucia, who gave the cacao and paid English
manufacturers to make it into chocolate. He had been treasuring the box
as a souvenir, but being the only article of food available, he filled
his pockets with the chocolate, which sustained him through many trying
hours.[3]
[3] See _West India Committee Journal_, p. 55, 1917.
We have already seen the high food value of the cacao bean: what of the
sugar which chocolate contains? Sugar is consumed in large quantities in
England, the consumption per head amounting to 80-90 lbs. per year. It
is well known as a giver of heat and energy, and Sir Ernest Shackleton
reports that it proved a great life preserver and sustainer in Arctic
regions. Our practical acquaintance with sugar commences at birth--milk
containing about 5 per cent. of milk sugar--and when one considers the
amazing activity of young children one understands their continuous
demand for sugar. Dr. Hutchison, in his well-known _Food and the
Principles of Dietetics_, says: "The craving for sweets which children
show is, no doubt, the natural expression of a physiological need, but
they should be taken with, and not between, meals. Chocolate is one of
the most wholesome and nutritious forms of such sweets."
Both the constituents of chocolate being nourishing, it follows that
chocolate itself has a high food value. This is proved by the figures
given below.
As with cocoa, we have first to know the composition before we can
calculate the food value. The relative proportions of nib, butter and
sugar, vary considerably in ordinary chocolate, so that it is difficult
to give an average composition: there are sticks of eating chocolate
which contain as little as 24 per cent. of cacao butter, whilst
chocolate used for covering contains about 36 per cent. of butter.
As modern high-class eating chocolate contains about 31 per cent. of
butter, we will take this for purposes of calculation:
AVERAGE COMPOSITION AND FUEL VALUE OF ENGLISH EATING CHOCOLATE.
_Composition_ _Energy-giving power_
_Calories per lb._
Cacao Butter 31.4 = 1,327
Protein (total nitrogen 0.78%) 4.1 = 76
Cacao Starch 2.3 } = 162
Other Digestible Carbohydrates, etc. 6.4 }
Stimulants { Theobromine 0.3
{ Caffein 0.1
Mineral Matter 1.2
Crude Fibre 0.9
Moisture 1.0
Sugar 52.3 = 973
----- -----
100.0 2,538
In Snyder's _Human Foods_ (1916) the official analyses of 163 common
foods are given. They include practically everything that human beings
eat, and only three are greater than chocolate in energy-giving power.
The result (2,538 calories per lb.) which we obtain by calculation is
lower than the figure (2,768 calories per lb.) for chocolate given by
Sherman in his book on _Food and Nutrition_ (1918). Probably his figure
is for unsweetened chocolate. The table below shows the energy-giving
value of cocoa and chocolate compared with well-known foodstuffs. The
figures (save for "eating" chocolate) are taken from Sherman's book, and
are calculated from the analyses given in Bulletin 28 of the United
States Department of Agriculture:
FUEL VALUE OF FOODSTUFFS.
_Foodstuff as _Calories
Purchased._ per lb._
Cabbage 121
Cod Fish 209
Apples 214
Potatoes 302
Milk 314
Eggs 594
Beef Steak 960
Bread (average white) 1,180
Oatmeal 1,811
Sugar 1,815
Cocoa 2,258
Eating Chocolate 2,538
[Illustration: PACKING CHOCOLATES AT BOURNVILLE.]
_Food Value of Milk Chocolate._
The value of milk as a food is so generally recognised as to need no
commendation here. When milk is evaporated to a dry solid, about 87.5
per cent. of water is driven off, so that the dry milk left has about
eight times the food value of the original milk. Milk chocolate of good
quality contains from 15 to 25 per cent. of milk solids. Milk chocolate
varies greatly in composition, but for the purpose of calculating the
food value, we may assume that about a quarter of a high-class milk
chocolate consists of solid milk, and this is combined with about 40 per
cent. of cane sugar and 35 per cent. of cacao butter and cacao mass.
ANALYSIS AND FUEL VALUE OF MILK CHOCOLATE.
_Energy-giving
power._
_Calories per lb._
Milk Fat and Cacao Butter 35.0 = 1,480
Milk and Cocoa Proteins 8.0 = 149
Cacao Starch and Digestible Carbohydrates 3.0 = 56
Stimulants (Theobromine and Caffein) 0.2
Mineral Matter 2.0
Crude Fibre 0.3
Moisture 1.5
Milk Sugar and Cane Sugar 50.0 = 930
----- -----
100.0 = 2,615
----- -----
It will be noted that the food value of milk chocolate is even greater
than that of plain chocolate. It is highly probable that milk chocolate
is the most nutritious of all sweetmeats. It is not generally recognised
that when we purchase one pound of high-class milk chocolate we obtain
three-quarters of a pound of chocolate and two pounds of milk!