Chemical Education Today
From Past Issues
Sweet Stuff by Kathryn R. Williams
A few months ago, I came upon the title “Recent Research in Sugar Maples” (1), which piqued memories of my upbringing in northern New York. Deciding it was time to savor a few sprinkles of sweet stuff from past JCE issues, I consulted the online index with “sugar” in the title field. In addition to botanist James Marvin’s discussion of Vermont’s sugar maple trees, the 42 retrievals cover topics varying from structure and nomenclature, demonstrations, and experiments for laboratories at all levels, to the history and technology of commercial sugar production. Of the historical accounts, I recommend C. A. Browne’s “The Origins of Sugar Manufacture in America” (2) published in the June and July issues in 1933. The first of this two-part series reviews the beginnings of sugar cane cultivation on the Indian subcontinent. Subsequent transplantation in the Middle East and the Mediterranean region led to development of processes for obtaining raw and refined sugar. Colonization brought cane farming and raw sugar production to the Americas. A number of famous inventors contributed to the progress of the sugar industry. Browne especially notes the triple-effect evaporator patented in 1846 by New Orleans native Norbert Rillieux. “Rillieux’s invention of the multiple effect is one of America’s greatest contributions to chemical technology.” Figure 1 shows an example of Rillieux’s design in a nineteenth-century Cuban sugar factory. The follow-up article traces the history of sugar refining first in Europe (primarily Holland) and later in New York. An excerpt from Browne’s text summarizes the overall process. The raw sugar was first stirred…to dissolve as much as possible of the adhering molasses. The washed sugar was then poured into conical molds and placed on the ground floor of the ‘fill-house’ until the molasses had drained away….[It was subsequently] dissolved…with
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the addition of milk of lime and animal blood [for coagulation]…The clarified solution then was passed through the bone-black filters…[and] concentrated in a vacuum pan to the granulating point when it was emptied into the so-called heater and stirred…until crystallization was complete. The magma of crystals was then poured into molds which were hoisted to the upper floors of the ‘fill-house’ for draining….When draining was complete the loaves were taken from the molds and…baked to dryness in the stove,…ground in a mill,…[and] stored in the shipping room.
Another article from 1933 furnishes historical information from the less distant past. In “Levulose, the Sugar of the Future” (3), James McGlumphy and Jack Eichinger of Iowa State College provide a comprehensive look at researches on fructose production from the Jerusalem artichoke, a native “weed” of the middle west. In an introductory note, editor Otto Reinmuth foresees the fructose industry as “a significant contribution to the ultimate solution of the agricultural problem,” referring to the “wallows and wails” of the farming economy in the Depression era. McGlumphy and Eichinger point out several desirable properties of fructose, such as the greater sweetness compared to sucrose and the decreased tendency for graininess in jellies and ice cream. They also cite limited epidemiological and clinical studies indicating “the possibility of its [fructose] application in the treatment or prevention of diabetes.” The kernel of the article traces the history of fructose production and major developments in the 1920s and 1930s by the authors and other Iowa State researchers. The photograph of their pilot plant (Figure 2) evinces many industrial advances compared with the Cuban operation in Figure 1 just three-quarters of a century earlier. The papers by Browne and by McGlumphy and Eichinger, as well as a number of other retrievals from the
Journal of Chemical Education • Vol. 78 No. 11 November 2001 • JChemEd.chem.wisc.edu
Chemical Education Today
Figure 1 (1933, 10, p 329, Figure 16). Interior of a Cuban sugar cane factory in 1857, showing a Rillieux triple-effect closed-coil vacuum evaporator on the upper level. Three vessels were piped in series with successively lower pressure vacua in each stage. Steam from the evaporating solution in the first vessel was sufficiently hot to boil the solution in the second, and the steam from the second boiled the solution in the third vessel.
online search, provide ample historical references to the role of chemists in the sugar industry. Interested readers can learn about more recent applications in Andrew Van Hook’s article “Some Chemical Problems and Prospects of the Sugar Industry” (4). The historical and commercial importance of sugars stems from their roles as sweeteners, and past issues of JCE also contain a sizable collection of articles with “sweet” in the title. Most noteworthy are three reports from a 1993 Division of Chemical Education symposium on sweeteners and sweetness theory, including a broad survey of sweet compounds (5) and an indepth look at sweeteners from plant sources (6). In the third paper in the series (7), Eric Walters describes current models relating sweetness to chemical structure and efforts to design new compounds with this property. He also cites several pertinent JCE articles missed by my title search. This brief taste of the past summarizes but a small fraction of the JCE materials on sugars and sweeteners. In-
Figure 2 (1933, 10, p 458). Pilot plant for levulose production at Iowa State College in 1933.
terested readers will find abundant food to add appeal to laboratory experiments as well as tidbits to sweeten chemistry lectures and improve the flavor of quiz questions. Literature Cited 1. Marvin, J. W. J. Chem. Educ. 1953, 30, 262–264. 2. Browne, C. A. J. Chem. Educ. 1933, 10, 323–330 and 421–427. 3. McGlumphy, J. H.; Eichinger, J. W., Jr. J. Chem. Educ. 1933, 10, 453– 463. 4. Van Hook, A. J. Chem. Educ. 1948, 25, 49–51. 5. Ellis, J. W. J. Chem. Educ. 1995, 72, 671–675. 6. Kinghorn, A. D.; Kennelly, E. J. J. Chem. Educ. 1995, 72, 676–680. 7. Walters, E. D. J. Chem. Educ. 1995, 72, 680–683.
Kathryn R. Williams is in the Department of Chemistry, University of Florida, PO Box 117200, Gainesville, FL 32611-7200;
[email protected].
JChemEd.chem.wisc.edu • Vol. 78 No. 11 November 2001 • Journal of Chemical Education
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