December, 1928
I N D U S T R I A L AAVDENGINEERING CHEMISTRY
entirely apart from the jam and jelly field. As near as can be determined, less that half the citrus pectin produced to date has been used in jam or jelly and the proportion so used is decreasing as the other uses are developed. These uses depend on the high emulsifying power and other physical properties of pectin due to its colloidal nature. The only standardization of pectin so far has been on the basis of jellying power, dry pectin preparations of 40, 80, 100, 120, 140, and 160 grade having been marketed, with distinct preference for the 100 and 160 grades. As there are no recognized standards for commercial pectin preparations, it is highly desirable that agreement be reached among producers and users of pectin and the officials enforcing the pure food laws as to standards for pectin preparations and methods for ascertaining the degree of conformity to such standards. It is hoped that close cooperation will be maintained among those interested in order that standards and methods may be agreed upon before too much diversity in these matters is developed by independent workers. Due consideration must be given to the use to which the product is to be put. Unfortunately commercial pectin is not an individual chemical substance that can be assayed for its degree of purity, as can sugar, for instance. It must be judged a t present by empirical tests for the qualities which make it useful. The tests for viscosity of solutions of known concentration here discussed and the direct determination of jelly strength are suggested as a start because they are applicable in connection with the best known use for pectin. Optical properties, pH of solutions a t definite concentration, ash content, freedom from color, flavor, and insoluble matter offer some promise as means of evaluation. We hope other workers will make known the tests they rely on in evaluating pectin and that laboratory workers, pectin users, and food-law enforcement officials will cooperate in the development of satisfactory standards and methods of testing. Summary
The utilization of the surplus citrus fruit crop through channels other than the fresh fruit market has been accomplished through the application of chemistry and engineering. The return from the sale of citrus fruit products does not cover the cost of production of the fruit, but such utilization aids in regulating to some extent the operation of the law of supply and demand. Among the commercial citrus products are citric acid, lemon oil, orange oil, concentrated orange and lemon juices, beverage sirups, peel products, and pectin. Of all these products pectin is the one requiring the most careful atten-
1307
tion to every detail of production and use. Some specific problems relating to its production and use are here presented. Bibliography 1-Ajon, Giorn. ckim. i n d . applicafa, 7, 17 (1924). 2-Ajon, Risisla ilal. essense profumi, 7, 125 (1925). 3-American Chemical Society, Division of Agricultural and Food Chemistry, J . Am. Ckem. Soc., 49, Proc., 37 (1927). 4-British Merchant Shipping (Anti-Scorbutic) Order in Council, April 22, 1927. 5-Chace, U. S. Dept. Agr., Circ. 232 (rev. 1925). 6-Chace, Bur. Plant Ind., Bull. 160 (1909). J . Am. Chem.. Soc., 48, 232 (1926). 7-Dore, C h m . - Z f g . , 28, 197 (1917). 8-Ehrlich, Z . angew. Chem., 40, 1305 (1927). g-Ehrlich, 10-Ehrlich and Sommerfeld, Biockem. Z., 168, 263 (1926). Ibid., 85, 118 (1918). 11-Fellenberg, 12-Gildemeister and Hoffmann, “The Volatile Oils,” 2nd ed., vol. 3, p. 41. 13-Goss. Hilgnrdia, 1, 15 (1925). 14-Hall and Wilson, J . A m . Chem. Soc., 47, 2575 (1925). ls-Irish, Univ. Calif. Agr. Expt. Sta., Bull. 372 (1925). 16--Jameson, J . Chem. Education, 3, 1117 (1926). 17--Maillard, Ann. ckim., 6 , 2 5 8 , 317 (1916). 18--hlead and Guilbert, Univ. Calif. Agr. Expt. S a . , Bull. 409 (19263. 19-Mead and Guilbert, Ibid., 439 (1927). 2 W h l y e r s and Baker, Univ. Del., Bull. 144 (1926). 21-Myers and Baker, Ibid., 149 (1927). J. IND.E N G . CHEX., 8 , 136 (1916). 22-McDermott, 23-Nanji and Xorman, J . SOL. Cizem. I n d . , 45, 337T (1926). 24-Nanji, Paton, and Ling, J . SOL.Ckem. I n d . , 44, 253T (1925). 25--Nelson, J . Am. Chem. Soc., 48, 2412 (1926). 26--Nelson, I b i d . , 48, 2945 (1926). Biockem. J . , 22, 749 (1928). 27-Sorman, 28-Ogston and Moore, Perfumery Essential Oil Record, 18, 126 (1927). I X D . ENCI. CHEM., 18, 1295 (1926). 29-0hn, 30-Parry, “The Chemistry of Essential Oils,” 3rd ed., Vol. 11, p. 319. 31-Perfumevy EssenfiaZ Oil Recoud, 13, 2067 (1922). END.CHEX., 12, 1176 (1920). 32--Poore, J . IND. Ibid., 15, 775 (1923). 33--Poore, J . Roy. N a v . M e d . Sewice, 11, 1 (1926). 34-Priston, 35-Priston, Proc. Roy. S O L .& f e d . , 19, 7 (1926). U. S. Dept. Agr., Bur. Agr. Econ., Circular on Sicilian Lemon 36-Smith, Industry, June 30, 1927. 37--Sucharipa, “Die Pektinstoffe,” 1925. J . Am. Ckem. SOL.,46, 146 (1924). 3S-Sucharipa, 39--Tarr, Univ. Del., Bull. 134 (1923). 4&Tarr, Ibid., 142 (1926). 41-Tarr and Baker, Ibid., 136 (1924). S. Dept. Commerce, IForZd Trade S o t e s on Chemicals and A l l i e J 42-U. Products, 2, No. 25, 3 (1928). 43--U. S. Patent 1,497,884 (1924). Calif. Citrograpk, 12, 422 (1927). 44--Wallschlaeger, Kolloidchem. Eeikeffe, 19, 115 (1924). 45--Wendelmuth, 46-Wil1, IND.ESG. CHEM.,8, 78 (1916). Biockem. J . , 22, 67 (1928). 47-Willimott, 48-‘A7illimott, Ibid., 22, 535 (1928). 49-Wilson, J. IND.EXG. CHEM., 13, 554 (1921). 50--Wilson, Ckem. M e t . Eng., 29, 787 (1923). 51-Wilson, IND.ESG. CHEM.,17, 1065 (1925). 52--Zoller, Ibid., 10, 365 (1918).
Chemistry and the Flavoring Extract Industry Bernard H. S m i t h VIRGINIADAREEXTRACT Co., I X C . ,BROOKLYN, N.Y.
I
N THE wide realm of chemistry there are few things more important than flavor. Did you have a good cup of coffee this morning? That was flavor. Was the wellbrowned bacon better than usual? Flavor again. Was the butter above reproach? Again a matter of flavor. Do you particularly enjoy the communications of Doctors Slosson, Herty, Little, and JT‘iley? That is literary flavor. For the dictionary tells us that flavor may be “a predominating or a characterizing quality of anything, especially of
literary 1%-ork.” The flavoring industry therefore covers a wide and interesting field. We have, however, more restricting definitions. The Oxford Dictionary says flavor is “that element in the taste of a substance which depends on the cooperation of the sense of smell.” It is that which gratifies the palate: relish-savor. It is well established that the tongue and the palate can appreciate only a part of what we know as flavor. Bitter and sweet, salt and sour are indicated by the tongue, but odor
1308
INDUSTRlAL AND EN( BNEERlNG CHEMISTRY
phys an important role in the sense of taste. I n considering flavor, therefore, we are primarily concerned with the aromatic and odoriferous substanc,es, and these, of course, may be either synthetic or natural. The sources of supply of both are built squarely upon a foundation of chemistry. The production of synthetics is nothing but organic chemistry, including interestiiig and sometimes difficult syntheses and exacting methods of purification. The prcimratioii and concentration of natiiral flavors are applied chemistry as well. They include distillation and fractionation, or perhaps separation, of the flnvoring ingredient by means of chemical combina-
Glsss-Lined Vats for Extraction of Vanilla by Percotation Procees
Vol. 20, No. 12
able, for both flavor and perfume work, that the higher esters are worthy of investigation. The so-called higher esters of anthranilic acid now offered seem to be impure or mixtures. FURTBER STUDIES OF ACETALS-The production of acetals, 01’ condensations of aldehydes and alcohols, should be useful for both the flavor and the perfume industry. A series of these products that might prove to be interesting and of commercial worth could be made. The same applies to condensations of normal aldehydes wiih ketones and to the esterification of the lower fatty acids with the higher iilcohols. VAmLLIN--In the United States, vanilla is the most widely used of all flavors, and, because of this, art.ifieia1 vanillin is doubtless the most important commercially of the flavoring synthetics. Last year well over 300,000 pounds of vanillin mere produced in the United States and sold at a price exceeding $2,000,000. It is now made mostly from eugenol. A cheaper source of supply would be advantageous. Vanillin occiirs in vanilla beans to an extent of from 2 to 3 per cent, but. there are present in the beans other distinctive flavoring substances, so that vanillin alone by no means replaces true vanilla with tlie discriminating. Recent,ly some alllied derivatires have been developed, which, in conibinstion with vanillin, more closely duplicate the true vanilla flavor. Doubtless further progress will be made aloug t.his line. That the ingredients of pure vanilla other than vanillin have real flavoring value is indicated by the fact that a pure vanilla extract containing 0.2 per cent of vanillin is approximately equivalent in flsvoring strength to a solution of vanillin alone containing 0.7 or 0.8 per cent of vanillin. There is an opportunity for further work to be done upon pure vanilla. This sliould include experiments with the various types of beans and their blends.
tion or other process dependent upon laborat.ory practice. To the flavoring chemist a background of physical chemistry and bacteriology is useful, a.s it is to chemists in the other food industries. The production of synthetic aromatic and odoriferous chemical products used in flavoring has greatly increased in recent years. A greater variety of flavored food used for desserts and tlie increasing use of confectionery and sweets, ice cream and flavored carbonated beverages have created a demand for flavors which the natural flavoring materials can hardly supply. Coumarin, artificially produced in 182G, was the first of the many synthetics now videly used for flavoring purposes. These materials cover a wide range of cheniicsl substances, most comnionly the alcoliols, aldehydes, and tlie esters and, to a smaller extent, the phenols and ketones. These include anetliol, citronella, menthol, safrol, and the higher alcohols and aldehydes, such as octylic. nonylic, and undecylic. fsrticularly important aldehydes are benzaldehyde, citral, and vanillin. Esters much used in flavors are amyl acetate, ethyl acet.nt.e, ethyl butyrate, and the esters of cinnamic, formic, propionic, salioylic, and “Sweatin$” Vanilla Beans by Coserins Them with Sfraw Mats valerianic acids. H. F. Judkins, of the General Ice Cream Corporation, The field of synthetic flavoring materials offers many o p portunit.ies for constructive research. The following prob- makes the following suggestion as a research problem: lems, among others, suggest themselves: What Is Pure Vanilla? Establish tests for determining the PIIYSICAI. ASPECTSOF ODORAND TAsrB-Much has been value of vnnilla extract. Make up a number of ice cream done in classifying by odor but little by taste. It might samples, flavored with combinations of different types of vanilla. be of value to develop a tahle describing as accurately as Try out on a large number of customers. As a result, list the combitiations as a guide to ice cream manufacturers. the worker can the taste resulting from the introduction of popular Take costs into consideration. All samples of ice cream sliould the methyl radical, the ethyl radical, etc., into various aro- be examined at different ages to note effect of so-called freezing matic groups, such as geraniols and linalools. For instance, out of flavor. The effect of aging vanilla in wood and in tinthe methyl ether of geraniol might smell like rose, yet taste lined vessels and other metal containers should receive consideration. All samples of vanilla should be tried in varying like WLix. Could the relation of odor to taste be tabulated amounts. in any understandable nr semi-scient.ific mariner? FURTHER &PUDIES OF HLGHER ESTERS OF ANTHRANILIC It is apparently true that a small quantity of pure vanilla Acrn-Certain properties of anthranilic acid are so valu- satiates or satisfies the sense of taste and that there is no
December, 1928
INDUSTRIAL AND ENCINEERING CHEMISTRY
1309
true that the pubadvantage i n inlie l a r g e l y buys creasing the quanwith the eye, it is tity u s e d a b o v e the maximum rebeginning to be quired. The exact. flavor-conscious. determination o f T a k e , f o r instance, the c a e of the ideal quantity in various types of t h e a p p l e . The food v o u l d be a p p l e s t h a t are helpful. generally offered in Lathrop and tlie c i t y are Ben Wrtlde’ h a v e Davis and many shown t h a t t h e good-to-look-at acid content of Western varieties of negligibleflavor. jellies has a very m a r k e d influence They a r e useful for roughage and u p o n t h e flavor. “crude fiber,” proT h e y f o u n d that Vanilla Beans Exposed to Sun and Air vided the core that there is always a is t h r o w n a w a y point in the blend of sugar and acid that gives the maximurn frnit flavor. Varia- does not include most of the apple. In tho Eden met.hod of tioo either m y from this point decreases the delectable fruit merahiintlising a,pples a sample bite was offered. If this plan flavor and its appeal to the appetite. The correct acid con- were in vogne today there would be few sales. Many fruits tent varies only slightly between the different fruit juices. are picked so green that they are insipid and flavorless when What is true with regard to the sugar and acid content in they come into the market. This is especially true of the jellies applies also to carbonated bemrages, ice cream, sher- pineapple. Peaches are now being cliilled and rushed to the bets, ices, confect,ionery, and similar sweetened products. distribnting centers, so tliat varieties that have real flavor are These factors for tlie most part have not been determined, available. and information in this field is greatly needed. For the benefit of the coiisumer>if not lor the flavor mannWhen working with natural flavors, the manufacturer must faeturer, should not the agricultural chemist use his influence concentrate them, and it is essential that he start with ma- wit,h his friend the horticulturalist to insure fruit of good terials of the highest concentration of flavor obtainable. flavor and merchandising rnet,hods that will help to get sucfi Ttiis is particularly true of fruits. There is a great difference fruit to niarkot in its best condition? in the flavors of different varieties of all fruits. It would The flavoring indnstry has a apecial f:rsainntion for the seem that in the past growers of fruit have frequently paid chemist. It offers him the opportunity for purely scientific inore attention to appear:tnce and shipping qualities than to work, with or without tlie practical problems of commercial flavor. In fact, one is tcmpted to believe that in mnny in- manufacture. fIere lie is dealing with those dclicute and stances flavor has not heen considered at all. While it is ethereabif not rornantie---anmias that bring pleasnre to the palate and add to the joy of living. % Prlrii Prod. J., 6. No. S, 11 (1827).
Chemistry and the Shortening Industry M . B. Graff Txe PROCTSR A N D Giataz.~. COMPANY, IYOKYDALB, Orno
HE term “shortening” has grown up in the trade to describe certain actions thst are seen to take place. It is applied to material used to produce a short texture i n the various types of baked goods. Several ingredients have some of this effect, bot the material chiefly used for the purpose is fat, and the name “shortening” is applied to tlie fats used in baking. Platt has pointed ont that fat is tlie oiily ingredient in the baking mixture which is not soluble in or readily miscible with water. It is therefore the ingredient wliich separates the wet particles of dough, shortens the fibers of gluten, and separates the masses of egg albumin or starch paste that have a tendency to mat together and bake into a hard cake. A number of fats are used, and have beeii used for years, as shortenings. Just which ones were used first it would be difficult to say. Some of the fats are shortenings in their natural state and some of them require processing to convert them into a desirable condition. The fats used for shortening have characteristics of more or less importance, depending upon the
T
purpose for wliioli they are to be used. Tliese eharacteristics are to some extent under the control of the producer, and often are best regulated Iiy tlie clieniisl. 1x1 some cases they are the direct result of chemical research. The elir\racterist.ics by which we judge shortenings may be classified as (1) color, (2) flavor arid odor, and (3) consistency, testnre, or plasticity. Among the fats used for shortening we natnr:dy think of butter. Whether it was tlie first one nsed or not, i t was certainly in early usc by both bakers and housekeepers. The problems of color, flavor, and consistency of butter art: fundamental in its control, and call for chemical as well as hactcriological investigation. Animal Fats as Shortening The problem of butter production for shortening, particularly for the baker, has been neglected. Although tlre tendency seems to be to produce tahlc butters of less and less flavor, tlie baker who uses butter for flavor wants all the flavor he can get. Tho texture of the butter is also of mneh