Part 13

3 × 4.1 = 12.3 3.5 × 9.3 = 32.55 4.5 × 4.1 = 18.45 12.3 + 32.55 + 18.45 = 63.30 1966.57 × 63.30 = 124483.88 124483.88 ÷ 100 = 1244, the No. of calories or energy (heat units) contained in two quarts of milk.

THE NEW OR "VIENO" SYSTEM

To a unit of food-energy which is equal to one hundred calories (see last paragraph on "Energy"), I have given the name of Vieno, derived from "vital" and "energy," and pronounced vi-eń-o. The Vieno system, therefore, will measure all foods by vi-en-os, or units of energy equal to one hundred of the chemist's calories. One vieno of milk is one-sixth of a quart, or two-thirds of an ordinary glass. From this it is readily seen that two quarts of milk will give twelve vienos of energy, or, if we wish to express it in the chemist's term, twelve hundred calories.

The table also states that milk has a nitrogen factor of .8. Therefore, if we wish to know the amount of nitrogen in the two quarts of milk, all we need do is to multiply the number =of= vienos by the nitrogen factor; 12 x .8 = 9.6, which figure represents the nitrogen consumption expressed in grams. (See explanation of fourth column of table.) These results are practically the same as those obtained by the old system of computation, but expressed in simpler terms. Thus we see that the vieno system of computing food values is unique in its simplicity, and will be a very material aid in putting Food Science on a practical basis.

NECESSITY FOR A SIMPLE SYSTEM

Things are commonly measured by volume, or by weight. That volume could not be made sufficiently accurate in the measurement of food values is evident. A bushel of lettuce leaves would contain much less food value than a bushel of wheat. Weight would seem to be a fairer way to compare foods, but all foods contain water, which may vary from five to ninety-five per cent. A pound of turnips, which is nine-tenths water, would not be comparable with sugar, which has scarcely any water.

Even if it were not for the water, weight would not be a fair method of comparison because some foods are of more value per pound than others, owing to their difference in chemical composition. For instance, a pound of butter gives about two and one-fourth times as much heat to the body as sugar.

As before mentioned, the two chief food factors which we ought to measure are energy-producing and tissue-building power.

All true foods when assimilated in the body produce some energy. In fact, only such substances as produce bodily energy, when combined with the oxygen taken in through the lungs, can be correctly termed food.

I have taken this energy-producing power of food as the best basis for measurement and comparison. The nitrogen could have been taken as a unit, and the energy figured by a table, but it is simpler to use energy as a unit (as given in column 3, p. 655), and figure the nitrogen in the various foods by means of a table which gives the amount of nitrogen per unit of energy. (Column 4, p. 655.)

Multiplication of units of energy (column 3) by the nitrogen factor (column 4) is necessary because the ratio of nitrogen to energy is different in each food.

EXPLANATION OF TABLE

In the table that follows, I have attempted to give in the simplest way the amount of each particular food that one vieno equals.

The second column shows, in the plainest language possible, what one vieno of food equals--as, one vieno of barley equals one ounce; or, one vieno of nuts equals one rounded tablespoonful, etc. This method is, of course, only approximate, as in some foods it is impossible to find a simple term to express the amount of one vieno. This is especially true of cooked foods because of the varied amounts of water contained. In such cases the way for the student to become familiar with a vieno is to weigh one pound of the raw material, and, after it is cooked, weigh it again, and then calculate the water content.

The definition given in the second column in the case of milk, butter, eggs, and cheese is fairly accurate. The description given in the case of cereals and bread is also fairly accurate. In the list of fresh vegetables, no attempt has been made to describe one vieno by volume, as, vegetables being loose and bulky, it is practical to measure them only by weight.

In the case of fresh fruits, one vieno has been defined as "one large orange" or "six plums," etc. In such cases allowance for the non-edible portion has been made; all weights given in the table consider only the edible portion.

In the case of nuts, the definition of a vieno in so many spoonfuls is fairly accurate. This is done only as an illustration, and not continued throughout the table. The student should use only the second column of the table for rough work, and to help him figure the approximate amount of one vieno.

The third column of the table, which gives the number of vienos or the amount of heat-energy in one pound, is the column to which the student should refer in his work. A pound of food referred to in this column invariably means one pound of the edible portion.

The way for the student to calculate the amount of food in one vieno is to take a pound of the food that he is to use and divide it equally into as many portions as the number in the third column. For example: If one pound of wheat is given as equal to sixteen vienos, the student should weigh a pound of wheat and divide it into sixteen portions, and each of these portions will equal one vieno.

The fourth column of the table gives the approximate nitrogen factor; that is, the percentage of nitrogen by weight in one vieno. This column is to be used for computing the amount of nitrogen in the diet under all ordinary circumstances. The student should take the total number of vienos of each food and multiply this number by the nitrogen factor. The product will be the approximate amount of the nitrogen consumed, expressed in grams. This is the direct method of ascertaining the amount of available nitrogen in food.

If in reading other works, the student finds the amount of nitrogen given in decigrams, he needs only to divide by ten in order to reduce it to this system, as a decigram is one-tenth of a gram. Likewise, protein can be reduced to grams, or decigrams, by a simple process of multiplication and division, as follows: Sixty grams of protein contains practically ten grams (one hundred decigrams) of nitrogen. Divide the amount of protein by six to change protein to the nitrogen unit. That is (Protein ÷ 6) = amount of nitrogen in grams.

The old-fashioned food table gave the amount of protein in per cent by weight, making it necessary to weigh the food, figure the amount of protein by multiplying the weight by the per cent, and then reducing this according to the rule given above. I explain this so that the student may be able to compare results expressed in the old table, with the vieno method, but in all practical work the student should use only this direct method which is much more simple and accurate.

The fifth column of the table gives the weight of one vieno in grams. This adds no new information, but only gives the weight of one vieno in the metric system. It should be used by those who wish to be accurate in their work, or by those who take a scientific interest in their dietary.

The last column of the table gives the actual amount of nitrogen in one vieno of food expressed in grams. This is the accurate figure from which the approximate nitrogen factor for ordinary use has been derived. For example: The actual amount of nitrogen in one vieno of chestnuts is .396. If this number is multiplied by the number of vienos of chestnuts eaten, we would have the actual number of grams of nitrogen consumed. Suppose ten vienos of chestnuts are eaten; we would multiply .396 by ten, which would give us 3.96 grams of nitrogen. For ordinary purposes, I use the nearest decimal, which is .4, and which I give in the fourth column as the nitrogen factor. Those who wish to figure the nitrogen with scientific accuracy should use the figures given in the last column of the table, as in the example I have given.

The Vieno system of food measurement is new, and is intended to give to the practitioner and to the housewife the greatest aid in balancing or proportioning the diet. I have therefore included in the following tables, all classes of foods, many of which I do not recommend or use in my scientific work.

TABLE OF FOOD MEASUREMENTS

DIRECT METHOD OF CALCULATING AVAILABLE NITROGEN IN FOOD

Multiplying the number of vienos (column 3) by the nitrogen factor (column 4) will give the amount of available nitrogen in the various foods, expressed in grams