Pectin

“ Pectose exists in the fleshy pulp of unripe fruit; during the process of ripening it changes to pectin; by cooking, pectin is changed to pectosic acid, and by longer cooking to pectic acid. Pectosic acid is jelly-like when cold; pectic acid is jelly-like when hot or cold. Cellulose constitutes the cell-walls of vegetable life; in very young vegetables it is possible that it can be acted upon by the digestive ferments; in older vegetables it becomes woody and completely indigestible. ”

“ DOCTORS have long used apple pectin in the treatment of diarrhea—especially with young children. Good results here have led to further discoveries of the effectiveness of pectin in the treatment of many intestinal disorders and also in the dressing of wounds and burns. ”

“ Fruit that is just a little underripe contains more pectin than the mature or overripe fruits. Pectin is the substance that makes jelly harden. This fundamental jelly-making quality does not exist in all fruits. Such fruits as currants, crab apples and grapes contain much pectin and are, therefore, considered excellent jelly-making fruits. ”

“ The chief requirement of fruits that are to be used for jelly making is that they contain acid and pectin. Pectin is the real jelly-making property of fruits. When it is in the presence of acid and combined with the correct proportion of sugar and the combination is properly boiled, a desirable jelly is the result. Without pectin, however, it is impossible to make the juice solidify, or jell. Pectin is closely related to the carbohydrates, but as it does not yield heat energy nor build tissue, its food value is not considered. ”

“ Specifies the temperature of food when packed into jars for canning, or the method of sweetening fruits for freezer packs.
Pectin—A substance occurring naturally in many fruits which causes the juice to thicken or gel after heating if the proper proportions of sugar and acid are present. Natural pectins are more prevalent in underripe fruit than mature or overripe fruit. Some fruits have enough natural pectins to make high quality jams and jellies. Others require addition of commercial pectins which are made from either citrus peel or apples. ”

“ The properties of the separated pectous compounds represent certain well-known characteristics of fruits, as these are found in cooking. Moist heat, as In any mode of cooking, produces upon these substances the chief results of ripening, and, if continued long enough, the results of overripening. Unripe fruits are made more edible and wholesome by cooking, owing to its artificial (imperfect) ripening of pectose. Fruit-jellies owe their substance to pectic acid, pectine, and slightly to parapectine, the products of early maturity, with the coöperation of sugar. ”

“ The prepared fruit is put in a damp jelly bag or several thicknesses of damp cheesecloth, tied, and hung to drip. The clearest juice will be free run, but yields increase if the bag is pressed or twisted. Re-straining this juice is recommended. Do not squeeze or press.
Jams, jellies, and preserves can be made with added pectin or without it, depending on the fruit. Fruits such as raspberries, strawberries, and peaches generally need added pectin. Apples, crabapples, currants, plums, grapes, and quinces—if not overripe—contain enough pectin and acid for good gel strength. ”

“ Suspended particles of gum or pectin may be removed by cautious precipitation with tannin, of which only an exceedingly small amount is usually necessary. It combines with the gelatinous substances better with the aid of heat than in the cold. There must be no excess of tannin used.
Another method of clarifying liquids turbid from particles of gum, albumen, pectin, etc., is to add to them a definite quantity of alcohol. This causes the former substances to separate in more or less large flakes. The quantity of alcohol required varies greatly according to the nature of the liquid. ”

“ Constituents of the Carrot.—These contain crystallizable and uncrystallizable sugar, a small quantity of starch, extractive gluten, albumen, volatile oil, pectin or vegetable jelly, alts, malic acid, and a peculiar crystallizable ruby-red, odourless, and tasteless principle called carotin. Pectin exists more or less in all vegetables, and is especially abundant in those roots and fruits from which jellies are prepared. ”

“ To be satisfactory, jelly must be made from fruit juice containing pectin and acid. Pectin is a substance in the fruit which is soluble in hot water and which, when cooked with sugar and acid, gives, after cooling, the right consistency to jelly.
Fruits to be used should be sound, just ripe or slightly under-ripe, and gathered but a short time. Wash them, remove stems and cut large fruits into pieces. With juicy fruits add just enough water to prevent burning while cooking. In using fruits which are not juicy cover them with water. Cook slowly until the fruits are soft. ”

“ In addition, cane sugar is contained in the majority of fruits. Pectin is also a carbohydrate that is found in large quantities in some fruits, while in other fruits it is lacking. This substance is related to the gums and to cellulose. Although it is one of the carbohydrates from which no food value is derived, it is of considerable importance, because it is responsible for the jelly-making properties of fruits.
14. In fruits that are not fully matured, or, in other words, green fruits, the sugar has not developed to so great an extent as it has in perfectly ripe fruits. ”

“ If the fruit is a little under-ripe pectin is formed through cooking, and it is often advisable to add some green fruit to the ripe fruit in making jelly. Nearly all failures in jelly making are due either to over-ripe fruit or to the use of too much heat, because in both cases the pectin is lost. ”

“ Roselles can be grown any place as easily as tomatoes or cabbage or any vegetable. It would certainly pay any one to make the experiment. The fruit is very rich in pectin, and not only gives a beautiful color when combined with any other fruit, but also adds much to the flavor. ”

“ Pecto-Cellulose.—A generic term applied to many important fibrous materials, such as flax, straw, esparto, bamboo, phormium, ramie, &c., which on alkaline treatment yield cellulose for paper-making, and a non-fibrous soluble residue of complex composition. These soluble derivatives are known as pectin (C32H48O32) , pectic acid (C32H44O30) , and metapectic acid (C32H28O36) . Although the soluble constituents of the pecto-celluloses amount to 50 per cent. by weight in most cases, no process for the recovery of the product in a commercial form has yet been devised. ”

“ Pec′tin, Pec′tine, a soluble gelatinising substance obtained from pectose; Pec′tōse, a substance yielding pectin, contained in the fleshy pulp of unripe fruit. [Gr. pēktikos, congealing—pēgnynai, to make solid.]
Pectoral, pek′tō-ral, adj. relating to the breast or chest.—n. armour for the breast: an ornament worn on the breast, esp. the breastplate worn by the ancient Jewish high-priest, and the square of gold, embroidery, &c. ”

“ Gentian root abounds in pectin; it also contains, to the extent of 12 to 15 per cent., an uncrystallizable sugar, of which advantage is taken in Southern Bavaria and Switzerland for the manufacture by fermentation and distillation of a potable spirit. [1616] This use of gentian and its consumption in medicine have led to the plant being almost extirpated in some parts of Switzerland where it formerly abounded.
The experiments of Maisch (1876) and Ville (1877) have shown tannic matters to be absent from the root. ”

“ The leaves, flowers, and roots, are employed for making ptisans. In Devonshire, this plant is termed by the farmers, "Meshmellish," also "Drunkards," because growing close by the water; and in the West of England, "Bulls-eyes"; whilst being known in Somerset as "Bull Flowers" (pool flowers) . The root of the Marsh Mallow contains starch, mucilage, pectin, oil, sugar, asparagin, phosphate of lime, glutinous matter and cellulose. An infusion made with cold water takes up the mucilage, sugar, and asparagin, then the hot water dissolves the starch. ”

“ In polarized light it is easily seen to be composed of successive layers.
Chemical Composition—It is probable that the fruits contain the same mucilage as Althæa, but we have had no opportunity of investigating the fact. Landrin [379] says it turns violet with iodine and yields no mucic acid when treated with nitric acid. Popp, who examined the green fruits in Egypt, states [380] that they abound in pectin, starch and mucilage. He found that when dried they afforded 2 to 2·4 per cent. of nitrogen, and an ash rich in salts of lime, potash and magnesia. The ripe seeds gave 2·4-2·5 per cent. ”

“ The value of a food-substance does not merely depend upon the amount and the relative proportion of its constituents, but also, and to a very great extent, upon their easy assimilability. There is but little doubt that the nutritive matters contained in the Swedish turnip when the bulb is fresh are very crude. By storing, certain chemical changes take place in the bulb, which render it more nutritious and palatable. A large proportion of the non-nitrogenous matters exist in the fresh root as pectin ”

“ Pectinatum, pectinate, is a pinnatifid leaf, whose segments are remarkably narrow and parallel, like the teeth of a comb, as the lower leaves of Myriophyllum verticillatum, and those of Hottonia palustris, Engl. Bot. t..
Inæquale, unequal, sometimes called oblique, when the two halves of the leaf are unequal in dimensions, and their bases not parallel, as in Eucalyptus resinifera, Exot. Bot. t., and most of that genus, as well as of Begonia. ”

“ The pectins more nearly approach to the composition, properties, and functions of the celluloses than do any of the other groups of organic compounds. They have been extensively studied in connection with the parasitism of certain fungous diseases which cause the soft rots of fruits and vegetables. These parasites usually penetrate the tissues of the host plant by dissolving out the middle lamella material, which may sometimes serve as food material for the fungus; but more often the parasite secures its food supply from the protoplasm of the cell contents. ”

“ Such fruits as peaches, cherries, and others containing but a small proportion of pectose, cannot be made into a firm jelly. All fruit for jelly should, if possible, be freshly picked, and before it is over-ripe, as it has then a much better flavor. The pectose, the jelly-producing element, deteriorates with age, so that jelly made from over-ripe fruit is less certain to "form." If the fruit is under-ripe, it will be too acid to give a pleasant flavor. Examine carefully, as for canning, rejecting all wormy, knotty, unripe, or partially decayed fruit. ”

“ Just as, in the germinating seed, starch, by contact with diastase, suffers fermentation with production of sugar, and as, in bruised and wetted mustard-seeds, sinigrin, by contact with myrosin, splits up into pungent oil of mustard and sugar, etc., so the crude pectose of green fruits, by contact of their pectase at the time of ripening, changes to the edible plant-jellies or pectous substances. Long boiling with water alone effects the same change. ”

“ Pectic acid, though it rarely exists ready-formed in the plant, can readily be obtained from it by the action of weak alkalis. It is best procured by boiling the pulp of turnips with a 10 per cent. solution of sodium carbonate for about half an hour. If an acid be added to the filtered liquid, pectic acid is precipitated as a transparent colourless jelly, which {29} dries up to a transparent horny mass. By the prolonged action of alkalis or acids, pectic acid is converted into metapectic acid (C8H14O9) , which may be obtained as a syrupy, strongly acid liquid. ”

“ A certain amount of waste matter is an advantage, to give bulk to our food; but persons with weak stomachs, who cannot eat certain kinds of fruit, are often able to digest the juice when taken alone.
Unripe fruits differ from ripe fruits in that they contain, starch, which during ripening is changed into sugar, and generally some proportion of tannic acid, which gives them their astringency. The characteristic constituent of unripe fruit, however, is pectose, an element insoluble in water, but which, as maturation proceeds, is transformed into pectic and pectosic acids. ”

“ Dosage: 30 Gm. or 1 ounce (U.S.P.) .
*Pepsinum (Pepsin.) , Pepsin, U.S.P.—Contains a proteolytic ferment or enzyme from the stomach of the hog.
White or yellowish scales, grains, or powder, having a slightly acid or saline taste and no offensive odor. Soluble in water (1:50) ; [Pg 156] nearly insoluble in alcohol. Digests 3000 times its own weight of coagulated egg albumen.
Action and Uses: Used to assist in the gastric digestion of proteins. Usually superfluous, since gastric juice generally contains sufficient pepsin to perform gastric digestion. ”

“ As food-materials, the pectous substances seem to be wellnigh indispensable to the health of man. They are not very nutritious; it is not known that they are fully digested into material which can be appropriated; and, being non-nitrogenous, they could scarcely yield tissue-building matter. What service they perform is not clearly understood. They may supply liquids important in digestion or assimilation. We obtain them in acidulous fruits, and in starchy tubers, and it is not clear how much of the value of each of these sorts of food is due to their pectous constituents ”