Chemistry and Confectionery'

In the following article a general outline of raw materials, manu- ary but necessary to keep remains a but the factured products, and attendant chemic...
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I N D CSI'RIAL AlVD &ENGINELFRING CHE'IIIISTIZ Y

Vol. IF, KO.4

Chemistry and Confectionery' By Stroud Jordan 3S2 PARKSIDE AvE., BROOKLYW, N.Y.

E' OKE searches the The manufacture of confectionery is fast becoming a specialized 'There should also be apliterature he industry, depending upon the careful selection and usc of all raw . pended to this outline the find that is the Oldest materials. Solution, evaporation, crystallization, dehydration, little used materials and madisintegration, blending, coloring, and flavoring-each plays a part. teriak whose use is secondform of confectiollerY Just how 01 when its In the following article a general outline of raw materials, manuary but necessary to keep began remains a but the factured products, and attendant chemical problems is giuen. up production. Above all, a clean and adequate supply one outstanding fact is that of water is a vital factor. from its discovery the confectionery industry dates its inception. The discovery of ~IANUFACTURED PRODUCTS honey led our early ancestors to seek the sources of raw mateA general classification of the more familiar lines of goods rial gathered by the bee and to attempt to make this confection will be given an$ an abstract that will cover the general on a larger scale. It was then learned that flowers, fruits, and grasses containedthis raw material,but manhad not heen manufacture will be outlined, although it will not be possible each item endowed by Nature with the special form of apparatus used by to FRUITS-Candied, crystallized, and preserved fruits may the bee in gathering these juices, he had to resort to expression of the whole material instead of removing the desired juices by be represented by citron, g!nW, Pineapple, orange, lemon, suction. It muat have caused Some when it was and grapefruit. Dried fruits may be represented by figs, first noticed that some of these sweet juices had lost their raisins, anddates, while the canned fruits may be represented sweet taste and developed a which was to be the by all materials such as the berries, fruits, and fruit products. Or may be cause of so much legislation a t a later date, while others had These products are used just as they are Obtained become thick and developed an increased sweet taste. Such cut into shapes and crYstallized* be Wed a observations made the first confection take the form of sun- pulp in flavoring the different kinds of confections>or may Or fondant coated. dried fruits and juices, but as time went on so did the search be dipped in for pew sweets, and this led to the discovery of sorghum and suGAn an aqueous Of is and sugar cane, which, in turn, started the development of our evaporated until only loto l2 Per cellt Of water present sugar industry. Confectionery depends in a large the resulting solution is suddenly cooled and run through a beater, we have the familiar types of casting or dipping measure upon the production of sucrose, but there are divided sucrose product is a mixture Of other products of equal importance, such as starches, partially creams* crystals in a saturated " O S e sirup, with or 16% converted starches, and plant and animal products, which air which is incorporated during the beating process. If are just as essential for The surface of the such a product is remelted and cast into starch a'earth is literally combed for raw materials, and if one could shape may be made, and this center may but realize the history, tradition, and romance that is bound most any then be crystallized or dipped in a coating of chocolate or up in a piece of candy, a more appreciative frame of mind dipping cream. Modification of this product by the addiwould be developed for this growing industry. tion of color and flavor gives the many types of cream goods which appear on the market. If albumin, gelatin, or milk is RAWMATERIALS added before the beating process, we get a product that is I n the following outline only those materials in most gen- very different from the original cream, containing air era1 use will be listed. To attempt a more elaborate dis- and an entirely different consistency. cussion would be to write a volume, and space does not perH~~~ CANDy-This name is common~y applied to a product mit. A classification is made under a general heading for that is made by dissolving sucrose in water and then evaporateach grade of material, and will serve to show the character of ing all or nearly all of the water. It is not possible to melt Fam materials employed. sucrose with any degree of success, for it will caramelize and form other decomposition products which ruin the taste (I) Honey-invert sugar, artificial honey compounds, and invert sugar and honey mixtures and color, but if the sucrose is first dissolved in w t e r and ( 2 ) Fruits-candied, desiccated, preserved, canned, and concretes: the wateris ev?porated, the sucrose will be left in a melted fruit juices, natural, evaporated, qnd desiccated mass may then be poured On a Warm (3) Sucrose-maple sugar, standard granulated, medium granulated, condition' This table and kneaded like dough or pulled to any desired cone granulated, soft yellows, plantation sugars, a n d washed sugars; cane up, maple sirup, sorghum sirup, and molasses sistency, and during either process the color and flavor may (4) Starch sugar-acid conversion sirups, malt conversion sirups, and be incorporated. Such a plastic may then be run rose; high conversion sirups and low conversion sirups into any desired shape, Or it may and ( 5 ) Starches-molding, soluble, converted (not sugars), thick and be pulled into stick form and cut into any length. If the (6) Gelatins-low beating power, high beating power, low M Y molten sucrose is pulled, it becomes opaque and white or, strength, high jelly strength in the case of colored goods, much lighter in color. This is '(7) Aibumin-natural, frozen, and desiccated due to the incorporation of air and the crystallization of suMilk-natural, evaporated, condensed, and powdered (8) crose, but if the molten mass is poured on a slab and allowed (9) Nuts-pecans, walnuts, filberts, peanuts, almonds, b r a d nuts, and qqconuts to cool without pulling or handling, it remains glassy and (10) Cocoa beans-cocoa powder, cocoa butter, and cocoa liquor transparent. If fruits and nuts are dipped in such a molten synthetic, imitations, and blends (11) Flavors-natural, mass and allowed to cool slowly, a jacket is formed which (12) Colors-certified and vegetable becomes hard and transparent, and we have the glac6 fruits and nuts with which we are all familiar. 1 Received February 25, 1924.

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April, 1924

IATDUSTRIAL A N D ENGISEERING CHEMISTRY

FRUITJmLIEs-The ordinary procedure of taking a fruit pulp or natural fruit, adding sugar and water, and then boiling to a jell is followed out. The resulting jelly is either cast into starch molds and allowed to set, or is poured on a cold slab, allowed to set, and later cut into desired shapes. The centers made in either manner may be crystallized or dipped in chocolate. Apricot pulp is very popular as a base for such ,jellies, but is slowly giving way to the more easily controlled fruit pectin, sugar, and natural flavors. COCONUT GooDs-If shredded coconut, sugar, and water are placed in a kettle and boiled to the proper consistency, poured o i l a table, and allowed to cool and stiffen, the resulting mass may be either cut into shapes and sugar-rolled or formed into balls and dipped in fondant. The former gives the familiar coconut eating pieces, while the latter gives the bonbons. The prepaIation of the coconut is simple, for the nuts are steamed, opened, peeled, shredded, and mixed with the proper amount of corn sirup and sugar, after which the mixture is cooked to the proper consistency. The water naturally present in coconut makes the addition of extra water unnecessary in most cases. Storage of such goods is R vital factor, for the shelf life is short. Sucrose in the jacket of the bonbons will crystallize and make the jacket spot, or the centers may become rancid from oxidation of the coconut oil that is naturally present. MARSHMALLOW GooDs-If a solution of gelatin, egg white, or a mixture of the two is added to corn sirup and sucrose in aqueous F,olution and the resulting mixture beaten, we have the underlying principle of marshmallow preparation. If a casting marshmallow is desired, the cook is carried higher, and the resulting material is then deposited in starch molds. If we wish a liquid or semiliquid marshmallow, it is not necessary to deposit in the molds and dry; so it is run directly into the container, allowed to cool, and then closed off. In drying the cast goods, the temperature must be well regulated, and if the liquid is to keep well it must be thoroughly cooled before closing so that sweating will be avoided. For some work a gelatin of low beating power and high jelly strength is desired, while in other cases the reverse is desirable. It is therefore essential that all lots of gelatin be examined carefully and not only checked up in the laboratory, but also handled in a regular sized batch under actual factory conditions. A comparison of the two results will classify the product and determine its use. PAsTILms-Pastilles and medicated confections have a sugar and sirup base in which gum arabic has been incorporated t o give the proper consistency and finish. Gum arabic is a recognized demulcent, and as such is a very valuable addition to this type of goods. Such a mixture is carefully boiled, blended, flavored, cast into starch molds, and dr.ied. The drying conditions for such goods are entirely different from those required for any other goods. Longer time and slower drying are necessary to keep down “casehardening,” and subsequent blowing, and the critical temperature must never be exceeded. Medications of many sorts are used, but the two most common forms are those containing licorice combined with menthol, thymol, or other like ingredients, and those containing very little or no licorice but using menthol, thymol, eucalyptol, salol, oil of wintergreen, and the like GUM GOODS (STARCHGooDs)-If thick or thin boiling starch is hydrolyzed and the proper amount of sugar and corn sirup added, we have a mass that may be colored, flavored, and cast into starch molds and dried. These gum pieces may then be wet on the surface and rolled in sugar, dusted with powdered sugar, or crystallized, to make the gum drops which are so familiar to every candy lover. The control of the initial hydrolysis, proper selec-

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tion of starch, and control of the water used-each plays an important part. COATED GooDs-If centers of jelly, hard candy, nuts, or any composition are placed in a revolving pan, wet with a concentrated sucrose solution, and dusted with sucrose crystals, the center will roll around and pick up a certain percentage of sucrose. The size and weight may be determined by control of the sirup and sucrose used. The shape of such centers must be such that they will roll easily and no sharp points or protrusions can be had. The initial coating is the most tedious and requires an operator who has had experience in this particular line of work. This gives sugar-coated nuts, jellies, and marshmallow work, which is also a regular article of consumption. A striking example of the fine art of pan work is the little white seeds so often seen as a top dressing on confectionery. These seeds are made by taking a grain of starch, cereal, or sucrose, and by alternate additions of sirup and powdered sugar building to the proper size and shape. ALMONDPASTE-Sweet and bitter almonds may be blanched by first immersing in hot water and then passing through the skinning machine. The result is a white, clean almond, free from dirt and skin; and this almond, when mixed with sugar and ground, will give a pasty mass, which may be cooked to the consistency of thick dough and packed in suitable containers. Vacuum containers are best, since they eliminate the chance of contamination from the outside and keep the p’aste in the proper condition. This product is used as a basis for much of th: fine pastries and in baking macaroons, which are composed of equal parts of sucrose, almond paste, and one-third the paste weight of egg white. This composition is worked to a dropping consistency, dropped on paper, and baked a t from 300” to 350” F. If the paste is worked up without the addition of egg white, it may then be shaped into any desired form, and furnishes the basis for marzipan goods, which are so familiar in certain parts of Europe. Almond products are all wholesome, have a very high food value, and it is a well-known fact that they contain two of the three generally recognized vitamins. CHOCOLATE PRODUCTS-chocolate may be divided into bitter, sweet, and milk products. The bitter coatings or liquors are made by roasting the blend of cocoa beans, husking, winnowing, de-germing, nibbing, and then grinding in some form of heated mill. This causes the ground beans to flow out in the form of liquor, which, when properly ground, gives the bitter chocolate coating, bitter chocolate, or cocoa liquor. If this bitter coating or liquor is now combined with finely powdered sugar and refined by running over the rolls, we have the sweet chocolate or sweet chocolate coatings, but it is necessary to add a given amount of cocoa butter for every pound of sugar employed, in order that the coating or liquor will flow properly. This cocoa butter may only be obtained from the expression of a certain amount of the original bitter chocolate liquor, and this leaves a press cake which contains some of the original fat but not enough to make it flow when heated. This cake is then powdered, cooled, and sieved, and gives the ordinary cocoa powder with which we are all familiar. If milk is incorporated in the sweet chocolate, we get the familiar milk chocolate, and this may be molded as such or mixed with nuts or fruits before molding. The preparation of chocolate-coated work depends upon the dipping of centers in the molten liquor either by hand, fork, or machine. The centers may be fruits, nuts, creams, jellies, marshmallow, nougat, or, for that matter, any kind of confection. Volumes might be written on this subject and many valuable treatises on cocoa products are to be had.

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INDUSTRIAL A N D ENGINEERING CHEMISTRY

Vol. 16, KO.4

CHEMICAL PROBLEMS

keep so long if an appreciable amount of moistlire is present, such as in creams, where it will run from 10 to 12 per cent, COKTROL OF RAWMATERIALS-one of the first and most and that the shelf life of such goods is rarely more than six important problems that confronts the chemist in the con- months. The coconut bonbons are even shorter lived, for fectionery industry is control of all raw materials. These five weeks is about a normal span under average storage materials must meet all local and Federal food requirements, conditions. I n justice t o these statements it must be said and many of these requirements differ. As an example, it that this life factor may be greatly prolonged if proper storage might be cited that Pennsylvania will not allow the presence facilities are provided, but where a jobber expects to store of sulfur dioxide in any foodstuff, while the Federal laws his candy in the same warehouse with unaffected products he allow up to 350 parts per million when the amount is stated cannot expect so long a life. on the label. The safe plan is to refuse all materials that If this factor is accurately determined for each individual contain sulfur dioxide, for then no mistake may be made. confection, it will mean that the jobber will not overstock There are also one or two states which refuse entry to goods and that the retailer will order oftener and keep fresher that have been colbred with certified colors, although the products on hand. This is the most vital problem confrontFederal laws permit such action. This means that not only ing the confectioners today and a t present is receiving the must these two states have vegetable colors, but neighboring smallest share of attention. states where there are jobbers who supply these states must STRUCTURE STUDY-TO predict the value of a metal it is also be included in this vegetable color list or the whole studied as to structure; so in confectionery there is also a business passed up. All this makes control difficult. correct structure for each individual. I n the incorporation TEMPERATURE CowrRoL-In the preparation of confec- of air, either in marshmallow or cream work, there are certionery it is almost necessary that sucrose shall have been tain sized particles which will give the best texture to the dissolved in water and a part of the water evaporated some- finished goods. The crystallization of sucrose in products where down the line of manufacture. In the production of should take place under given conditions, and if these condifondant or cream there is a definite boiling point for each tions vary, the structure study will reveal the fact, for the solution intended for a special cream, and the boiling must size of the crystals determines the consistency.to a large be stopped and the batch removed and cooled quickly if the extent, This is particularly true in goods where powdered sugar-water ratio is to be kept proper. Accurate tempera- sugar is incorpnrated and the resulting mixture fined, such as ture is also a requisite in the preparation of hard candy chocolate coatings, for the size of the particles of sucrose dewhere it is desired to remove all or nearly all of the water termines whether the piece will be gritty or whether the mass present. And so in every process where evaporation takes has been properly mixed, This particular problem has been place an accurate temperature control is essential to uniform given but scant attention, but is slated for a more exhaustive and satisfactory production. study in the near future. MOISTURE CONTROL-A difference of 1 per cent in moisture COLORINVESTIGATIONS AND CONTROL-The shade recontent in a finished product often spells success or failure quired for a given product will vary if the amount and quality in its carrying and keeping qualities. I n marshmallow of color is not carefully watched. This is done by determinproducts of the liquid or semiliquid type, the presence of a ing a color factor under the red, green, and blue glass, and slight excess of moisture will break the emulsion and cause by referring each subsequent batch of color to the same standthe sirup to separate on standing. Solid marshmallows ard. Then there is the problem of using slightly off colored will become soft and sticky and mold or ferment if they con- sirups in colored goods, and it is evident that we must know tain too much moisture. I n cream goods the presence of how much yellow is in a batch of heated sirup if we are t o excess moisture will cause sweating when closed in containers, make a green that is comparable with the preceding batch, and this sweat will condense on the surface and cause the for the blue must be increased and the yellow decreased in confection to fall in holes and become discolored. It is be- such a sirup. The properties of a color must also be recklieved that a large part of the trouble experienced by manu- oned with, and me find that certain colors will not stand up facturing confectioners is directly traceable to the presence under light as well as others. Indigo is one of the most of excess of or deficiency in moisture. susceptible of all colors to light changes where the tint is INvERsIoN-If an aqueous sucrose solution is boiled for a delicate, and all colors in which it is used must be carefully prolonged time, it gradually decomposes, forms acid-like guarded from the light if the color is to hold. Acids affect products, and will invert itself. This fact cannot-be ignored certain colors, alkalies affect others, and the heat of the soand a close control of all boiling operations must be kept. lution to be colored also lends a hand in the color destruction. Inversion will also take place a t ordinary room temperature, It is also necessary to be able to duplicate certified shades except more slowly, in all products that have an acid nature, with vegetable shades, and this is only possible by keeping the and the shelf life of such articles is not so great as where no most complete records of all colors used. acid is present. The time required to cool a cook of sucrose FLAVORING-In the use of flavors the ability to withstand also has a direct bearing on the invert sugar content, and this heat and loss on evaporation is of prime importance. The is especially harmful in sirups that are to be used for crys- three common types of flavors have already been mentioned, tallization purposes. but it is well to say that the synthetic flavors are never SHELFLIm-The insurance companies reckon an average absolutely uniform, unless furnished by the same supplier, life for each human individual; the steel springs in your and the imitation flavors are impossible of duplication from motor car have a fatigue point beyond which they often snap different sources-all of which makes it bad business to buy very unceremoniously; and everything has a normal span of these flavors if they can be made, Natural flavors and exexistence, candy being no exception. This fact has not been tracts are fairly uniform, but there are unscrupulous manuwell recognized in the past, but it will most surely receive its facturers who dilute these flavors to meet a competitor’s price share of attention in the coming years. This factor is differ- and undersell him, and unfortunately the purchasing agent ent for each individual blend of materials, and as an example depends largely upon the printed label as a guide. Close we need only cite hard candy, in which there is little or no check must be had on these flavors a t all times. It is betwater and which when sealed away from air will keep almost ter to make all natural flavors if it is possible and the usage is indefinitely. In contrast, we find this same sucrose will not great enough to warrant.

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I N D U S T R I A L A N D ENGINEERING CHEJfISTRY

April, 1!)24

DECOLORIZING PROBLEMS-There are many decolorizing carbons that will remove color very effectively. This does not mean that it will be profitable for the confectioner to use raw sugar and r e h e it by this process or to decolorize any of his products unless the amount to be handled per day will warrant such a layout. The contributory costs make the handling of small amounts prohibitive, and the employment of a pressman who knows his work is essential, regardless of the quantity handled. He must be used full time on this operation and the presses should run capacity at all times; otherwise the loss of sugar in press washing and the loss of time from the intermittent character of the work make such an operation prohibitive. Another fact which cannot be overlooked is that decolorized sirups made from raw sugar cannot be used to supplant sirups made from refined sugar

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and water. The process of decolorizing does not remove all ash or other impurities, and on a high boil these have a decided effect on the sirups. DEVELOPMENT \\ToRK-such work is indispensable if handled properly, but utter folly if the reports are to be read and pigeon-holed. The development work in the confectionery industry does not differ from that in any other industry and the same rules apply; so it will not be attempted to lay out any extensive program. This work is confined to the production of new goods, working out new processes, and eliminating unnecessary operations wherever possible. This is rather a general statement, but it is not necessary to enlarge upon it, for development work is comparable in all industries and those familiar with one line may draw their own conclusions as to what, should be done along this line.

IJse of Ethylene in t h e Coloring of Citrus Fruit' By E. M. Chace and F. E. Denny LABORATORY OF FRUIT A N D VEGETABLECHEMISTRY, BUREAUOF CHFMISTRY, Los ANGELES, CALIF.

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Lemons are Picked accordThe use of ethylene f o r the forced curing of citrus fruits is increasing rapidly in Southern California. During the past year ing t o size without regard nlay be permissible to review briefly the hundreds of carloads of oranges and lemons have been colored by the to their Color. During process, with results that have been highly satisfactory to those in Some Part of their season, a t situation in the citrus inleast, all of these, together dustry which renders the charge of the work. The increasing popularity of the method is due with Florida and Porto Rico coloring of citrus fruits neeto its many advantages Ouer the kerosene stove system, I t is more essary. Coloring can be convenient; thefire risk is reduced: the necessity for constant supergrapefruit, are colored by legitilnate or illegitimate, vision is auoided; workmen are not exposed to the foul-smelling, dePendi% upon its use. To tear-compelling atmosphere generated by the stoves; the fruit is OLD METHOD color an immature fruit in never sooted with smoky stoves: no odor is imparted to the finished such a Tvay as to give the producf; during the warm season the wilting and shrinking of the fruit formerly produced by the heat of the stoves is prevented;finally, It has been known for a impression that it is mature it should be pointed out that the method can be rigidly standardized 1ong.time that when citrus is unlawful, but there Seems with respect to temperatures, humidities, and gas concentrations in fruit was storedin rooms or t o be no sound reason why under tents containing oil mature fruit, desirable in a manner productive of uniform results. every way except as to color, burners of any type the greenish color would disapshould not be colored, if its food value is not lowered by the process. pear. For some time it was thought that this change was In citrus fruits, color is by no means a reliable indication brought about by heat, and several coloring rooms were heated of maturity. Thus, the California Valencia orange, which by steam, but without success. Later, Sievers and True2found matures during the summer about fifteen months after its that the products of combustion were necessary for coloring. blossoming time, is often better colored in December, when It then became customary to build the coloring rooms as it is immature, than in the following August, when it is fully tightly as possible and to impede the combustion of the keromatured. The writers have observed, both with this orange sene stoves so as to produce as evil smelling by-products as posand with grapefruit, that when subjected to the heat of the sible. Within the past few years this idea has been abandoned second summer of its growth these fruits will take on a green- by some packers, and where stoves are used frequent vent,ilaish tinge which is quite pronounced a t the stem and blossom tion is resorted to and no effort is made to bring about partial ends. A. lemon colored on the tree has no advantage in combustion. Under these conditions coloring is somewhat eating quality over one colored artificially, and has a decided slower, but texture and other conditions are better. disadvantage both as to color and keeping quality, so that At the time work was begun on the project, several types there seems to be no objection to the artificial coloring. of coloring rooms were in use, and there were about as many Purchasers pay more attention to appearance than t o the variations in the method of applying the stove gas as there more defqirable qualities, and naturally the producer makes were packing houses. every effort t o render his product pleasing in this respect. The coloring or sweat rooms, as they are commonly called, It is well enough to theorize about educating the consumer usually have a capacity of from one to two carloads of packed to use green-colored fruit, but no grower or association of fruit, or from 750 to 1500 field boxes. They are constructed of hollow tile, cement, wood, or even plaster board, and in growers dares risk his profits on the theory. The Washington Navel orange of California, the Parson some cases the walls are packed with sawdust. The rooms Brown orange of Florida, and the Satsuma orange of Alabama are situated on the ground floor or in the basement, and are are satisfactory to the taste before they are to the sight. usually provided with adequate means for ventilation. The Valencia orange of California sometimes resumes a I n the rooms of the older type, blue flame kerosene stoves greenish color if left on the tree during its se,cond summer. are placed directly in the room or in the basement beneath 1 Received February 9, 1924. 2 Bureau of Plant Industry, Bull. 282 (1912).

T THE beginning it