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 much for the old valuations; let us now attempt by modern methods to estimate the food value of cacao and its preparations.
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:
Calories per lb.
|Protein (total nitrogen 2.3%)||11.9||=||221|
Other Digestible Carbohydrates, etc.
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:
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.
Calories per lb.
Other Digestible Carbohydrates, etc.
("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:
|Kind of Beverage||Water||Protein||Fat||Carbohydrates||Fuel value per lb.|
(0.5 oz. to 1 pt. water)
(1 oz. to 1 pt. water)
(0.5 oz. to 1 pt. water)
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."
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.
We have noted above the high percentage of nutrients which cocoa contains, and the research conducted by J. Forster 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 (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.
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."
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.
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).
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.
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:
Calories per lb.
|Protein (total nitrogen 78%)||4.1||=||76|
Other Digestible Carbohydrates, etc.
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:
|Bread (average white)||1,180|
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.
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|
|Milk Sugar and Cane Sugar||50.0||=||930|
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!