This section is from the book "Meals Medicinal", by W. T. Fernie. Also available from Amazon: Meals Medicinal: With "Herbal Simples" Curative Foods From the Cook in Place of Drugs From the Chemist.
The throat gland (Thymus) of the calf is the true Sweetbread; but what is known anatomically as the Pancreas, or Stomach-bread, passes likewise commonly under the name of Sweetbread as supplied by the butcher. Bach of these is good for invalids as a light food, easily digested, as long as the animal killed to supply them has still lived on milk, but they change their character when the calf begins to eat grass, and hay. It is the Pancreas, or Stomach-bread, which has a function to digest starches, and fats, after they leave the stomach, and when they first reach the intestines. This Pancreas secretes a fermenting principle which may be collected from the animal, and procured through the chemist as Pancreatin, for mingling with sugar of milk, or with cane sugar, so as to digest either starches or fats outside the body; also it may be mixed with preparations of alcohol (rum, cognac, or wine), and drunk as a nutritive, stimulating beverage; but these admixtures are insidious as to their intoxicating effects, because their absorption is rapid, so that small quantities will inebriate, the taste of the alcohol becoming concealed.
Both the throat Sweetbread, and the stomach Sweetbread, of the calf, are cellular organs held together by loose connective tissue, so that when taken as delicate foods they are easily dissolved in the stomach. Nine ounces of the true Sweetbread are completely disposed of by a healthy stomach in two and a half hours, while a similar weight of beef-steak demands at least four and a half hours for its complete digestion. But the cells of these Sweetbreads are chiefly composed of nucleo-proteid, for which reason (as explained concerning kidney foods, and liver) they are likely to disagree with gouty persons.
It seems proved that the Stomach-bread (Pancreas) has to do with the occurrence of diabetic disease. If the organ is extirpated from a living dog, severe diabetes is brought about. For this reason, on the modern principle of treating with a curative aim the diseased condition, or perverted function of a human glandular organ by giving portions of the corresponding glandular organ taken freshly from a recently slaughtered, sound animal, (or extracts made therefrom by the chemist), it may be found highly useful to administer the Stomach-bread, or portions thereof, cooked or uncooked, from time to time to the diabetic patient, carefully watching the effects produced.
The Stomach-Bread Of The Sheep may be likewise experimentally employed in the same manner. The juice secreted thereby, as well as by the Stomach-bread of the calf, closely resembles our saliva, and contains a similar ferment, which can convert starch into dextrin, and dextrin into sugar (glucose), more powerfully indeed, and more completely than the saliva serves to do. "Pancreatin" is the concentrated juice of the Stomach-bread procured from animals, and prepared by the chemist for emulsifying fatty foods, and starches, before they are taken as food, thus saving the Stomach-bread from work to which in the dyspeptic person it is unequal. For making this the animal Pancreas (Stomach-bread) is rubbed down with glycerin, so that its solvent principle, "trypsin," may be actively retained. The Pancreatin does its work best when in neutral, or alkaline solutions. Within the human system the Stomach-bread is chiefly stimulated by the acid gastric juice which reaches it from the stomach. Formerly a "Sweetbread" signified also in England a bribe, or douceur. "I obtained that from the fellow with a few Sweetbreads which I gave him out of my purse." In Jane Austen's Novel (Emma) the amiable, pottering, old valetudinarian, Mr. Woodhouse, is given to propound views of rigid strictness concerning matters of the table, which views have a somewhat humorous vein; they rise, however, almost to a tragedy when poor Mrs. Bates is deprived thereby of her Sweetbread at supper, just because the accompanying asparagus is decided by him to be imperfectly cooked. "The baked apples, and biscuits" (which came after) "were excellent in their way, you know; but there was a delicate fricassee of Sweetbread, and some asparagus, brought up at first, and good Mr. Woodhouse (fastidious, and a fidget), not thinking the asparagus quite boiled enough, sent it all out again.
Now there is nothing grandmamma likes better than Sweetbread and asparagus, so she was rather disappointed; but we agreed we would not speak of it to anybody for fear of its getting round to dear Miss Woodhouse".