Clarence A. Smith

Is unpalatable food properly digested

It is well known that different psychic stimuli promote or retard the secretion of digestive juices. The following experiment was conducted to determine whether the ultimate return to the body from unpalatable food was different from the return from the same food palatably served. The experimental procedure was simple. A 7-day period during which the subjects were on a uniform diet, served palatably and amid pleasant surroundings, was followed by a 2-day period during which the same diet was fed in an unpalatable condition and in dirty and unpleasant surroundings. The food was rendered unpalatable and unappetizing by the following treatment. All the food ordinarily used for each meal (meat, biscuits, jelly, cornstarch pudding, oleomargarine, etc.) was stirred together in a large, flat porcelain dish. The dish itself was smeared with animal charcoal, as was the beaker used as a drinking glass. The table was dirty and strewn with dirty dishes. A little indol was sprinkled about under the table. The subjects were kept in ignorance of the constituents of the unpalatable mixture. The food was so unpalatable that one subject vomited his first meal shortly after he had eaten it. The following table shows the findings on the other subject. The differences in utilization of the palatable and unpalatable foods were quite small as were the variations in nitrogen retention. This short test indicates that flavor is not the outstanding dietetic asset that some people would have us believe.

The Addition of Yeast to a Milk Diet.

The experiments were made on white rats, one group of rats being fed a diet of pasteurized milk and a second group being fed a milk and yeast diet. The rats receiving the yeast made more satisfactory growth gains than did the rats receiving no yeast. Inasmuch as milk has been shown to be low in the water-soluble “B” vitamine, which is present in high concentration in yeast, it would seem that yeast may be found to be an important dietary adjunct for use in baby feeding.

The Antiscorbutic Potency of Strawberries.

Several guinea pigs were fed a diet of oats, milk, and hay until they were decidedly scorbutic. They were then given expressed strawberry juice, either fresh juice or juice previously boiled for five minutes. The symptoms of scurvy were overcome within seven days by the administration of ten c.c. per day of either boiled or unboiled juice. Strawberries, therefore, appear to be relatively rich in water-soluble C, and their content of this vitamine is not seriously decreased by five minutes boiling.

The nutritive value of extra-yeast bread

Eleven albino rats were placed upon a diet containing besides inorganic salts and butter fat in adequate amounts, a bread made from white flour in the ordinary manner containing the usual amount of yeast, the liquid used in preparing the dough being half milk and half water. Another group of eleven rats of the same average weights were placed upon a diet similar to the preceding, except that 5 per cent. of dried yeast was added to the flour and some extra fresh yeast added to raise the dough. The rats on the ordinary bread grew very poorly, gaining on the average only 18 grams in 9 weeks. The rats on extra-yeast bread grew much better, gaining 59 grams on the average in 9 weeks. The superior nutritive value of the extra-yeast bread was ascribed to its high content of water-soluble B and to the supplemental action of the complete protein of the yeast.

The vitamine content of honey and honeycomb

Dutcher 1 concluded from experiments on pigeons that honey contained a small but negligible amount of antineuritic vitamine. Faber 2 did not find honey to protect against scurvy in guinea pigs. The present authors carried out feeding experiments on albino rats, to determine whether the growth promoting accessories fat-soluble A and water-soluble B were present in white clover honey or in a mixed strained honey, and whether these honeys protected guinea pigs against scurvy. Rats fed a diet lacking water-soluble B when compared with rats fed the same diet except that half of the carbohydrate was replaced by an isodynamic equivalent of either of these honeys, showed in five weeks an average gain in weight of only five grams in favor of the honey-fed rats. Similar experiments on the addition of the strained honey to diets deficient in fat-soluble A showed almost similar failure of growth. The addition of comb honey, however, brought about cessation of decline and distinct gains in weight. The addition of twenty per cent. of honey to the diets of guinea pigs did not prevent, or appreciably delay, the development of scurvy in these animals.

Gastro-intestinal studies XI. Studies on the relative digestibility and utilization by the human body of lard and hydrogenated vegetable oil

Two normal men were the subjects of the experiment, which was conducted in two periods of eight days each, separated by an interval of three days. The diets were so arranged that the fat, ingested during the first period, was mostly lard, while that of the second period was mostly hydrogenated vegetable oil. The daily feces were analyzed for total fat, fatty acid, and neutral fat by the Saxon method. The average percentage of digestion of lard was 96.75, and of the hydrogenated vegetable oil, 96.3, while the average utilization percentages were 94.7 and 93.35 respectively. It is thus apparent that the hydrogenated vegetable oil used in this experiment was as satisfactorily digested and utilized by normal men as was lard.