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NutritiveNutritive SweetenersSweeteners FromFrom CornCorn CONTENTS Member Companies and Plant Locations ...... 2 Foreword ...... 3 Historical Perspective ...... 4 Research and development orientation ...... 5 Technology aimed at needs ...... 7 Growth, Development and Diversity ...... 7 CONTENTS Classification and Nutrition ...... 9 Classification ...... 9 Corn sweeteners in nutrition ...... 10 Technical Background ...... 11 Corn ...... 11 Starch ...... 13 Crystalline dextrose ...... 14 Dextrose isomerization ...... 15 Manufacture ...... 17 Corn ...... 17 Dried corn syrups ...... 18 ...... 18 Dextrose monohydrate...... 19 Dextrose anhydrous ...... 19 High corn syrups ...... 19 Fructose ...... 20 General Characteristics ...... 21 composition ...... 22 Solids content...... 23 ...... 24 Properties and Uses ...... 25 Physical properties ...... 25 Solubility ...... 26 Hygroscopicity ...... 26 Textural characteristics ...... 26 Molecular properties...... 27 Viscosity ...... 30 Chemical properties ...... 31 Fermentability ...... 31 Reducing characteristics ...... 31 pH values of corn sweeteners ...... 34 Analytical Examination ...... 34

Corn Refiners Association 1701 Pennsylvania Avenue, N.W. Washington, D.C. 20006-5805 202-331-1634 Fax: 202-331-2054 www.corn.org

1 8th Edition Copyright 2006 MEMBER COMPANIES PLANT LOCATIONS Archer Daniels Midland Company Plants: P.O. Box 1470 Cedar Rapids, Iowa 52404 Decatur, Illinois 62525 Clinton, Iowa 52732 Columbus, Nebraska 68601 Decatur, Illinois 62525 Marshall, Minnesota 56258-2744

Cargill, Incorporated Plants: P.O. Box 5662/MS 62 Blair, Nebraska 68008-2649 Minneapolis, Minnesota 55440-5662 Cedar Rapids, Iowa 52406-2638 Dayton, Ohio 45413-8001 Decatur, Alabama 35601 Eddyville, Iowa 52553-5000 Hammond, Indiana 46320-1094 Memphis, Tennessee 38113-0368 Wahpeton, North Dakota 58075

Corn Products International, Inc. Plants: 5 Westbrook Corporate Center Bedford Park, Illinois 60501-1933 Westchester, Illinois 60154 Stockton, California 95206-0129 Winton-Salem, North Carolina 27107

National Starch and Chemical Company Plants: 10 Finderne Avenue Indianapolis, Indiana 46221 Bridgewater, New Jersey 08807 North Kansas City, Missouri 64116

Penford Products Co. Plant: (A company of Penford Corporation) Cedar Rapids, Iowa 52404-2175 P.O. Box 428 Cedar Rapids, Iowa 52406

Roquette America, Inc. Plant: 1417 Exchange Street Keokuk, Iowa 52632-6647 Keokuk, Iowa 52632

Tate & Lyle Ingredients Americas, Inc. Plants: (A subsidiary of Tate & Lyle, PLC ) Decatur, Illinois 62521 P.O. Box 151 Lafayette, Indiana 47902 Decatur, Illinois 62521 Lafayette, Indiana 47905 Loudon, Tennessee 37774

2 The of sweetness stands unique among our sensory . Delving into the roots of the word “sweet,” we find the Latin equivalent suavis—delightful—and the Greek root Hedys—pleasant. In Old English, these roots evolved into the word “swete,” from which our present term is drawn. FOREWORD Regardless of its name, humans have always sought the taste of sweetness. As the search for spices motivated earlier ex- plorers, so has the search for sweetness moved both people and institutions.

For many years, these efforts concentrated on a tropical grass, cane, and the . But since the early 1800s, they have increasingly moved in the direction of a native American crop ... corn. Today, as this booklet de- tails, nutritive sweeteners from corn have become America’s premier sweeteners.

Many years of meticulous research have brought the corn refining industry to this point. But by no means has the search for new forms and functions for corn sweeteners ended—it will continue, and the corn refining industry looks forward to playing a central role.

Audrae Erickson President Corn Refiners Association

Readers are advised that the information and suggestions con- tained herein are general in nature and that specific technical questions should be referred to the Association or member com- panies. Questions concerning the price and/or availability of products described should be directed to individual Association members.

3 The discovery that starch high fermentability. could be transformed into sweet substances by heating Though early success for with dilute acid is nearly 200 sugar from the beet source HISTORICAL years old. It was made in a appeared promising, PERSPECTIVE Russian ceramics laboratory Napoleon’s defeat at the by the chemist G.S.C. Battle of Waterloo lifted the Kirchoff who was seeking a blockade and most of the substitute for the Gum Ara- new sweetener activity bic that was then used as a ceased. Beet processing was soluble binder for clay. later revived under govern- ment subsidies. Subsequent work by other scientists demonstrated that The first commercial starch starch is a polymeric form of hydrolysis products ap- that could be broken peared in the U.S. in 1842 down to D-glucose by hy- and reached significant pro- drolysis or conversion. And portions by 1857. While so the foundation was laid potatoes served as the early for a starch-derived sweet- source for starch and , ener industry. dextrose (originally identi- fied as corn sugar and called Sweeteners were very much cast or chip sugar), was pro- in the public eye at the time duced from at a of Kirchoff’s discovery. plant in Buffalo, New York France was at war with Brit- in 1866. In Europe, the ain and cane sugar imports starch industry developed from the West Indies had principally around been closed to her by the starch—derived as a by-prod- British blockade of Euro- uct of a crop—but in pean ports. The sugar short- the United States, it - age was so critical that Na- ished with the corn crop. poleon was under heavy Corn starch hydrolysis and political pressure to provide refining furnished a major an alternative ingredient to outlet for a raw material satisfy the well-developed used originally in over- French taste for sweets. whelming proportion for From this pressure came animal feed. In drawing on government financial sup- the native grain as a source port for investigating sugar of industrial products for production from both beets both feed and new food ap- and grapes. “Starch sugar” plications, the corn refining attracted interest in industry has developed a and distilling because of its uniquely American identity

4 and presents a remarkable dextrose hydrate—the end chapter in man’s “pursuit of product of complete starch sweetness.” hydrolysis. The second was the commercialization of very low conversion prod- RESEARCH AND ucts (i.e., maltodextrins) in DEVELOPMENT the mid-1950s. With the ORIENTATION addition of these two prod- From its inception, the corn ucts, a wide spectrum of refining industry has been starch conversion ingredi- sensitive to the needs of its ents was now available to customers. In its early years, the food industry. much of the industry’s effort was aimed at developing Sweetness differences re- sweeteners with widening mained a major challenge to application and appeal. In- the corn refining industry creasing industrialization of until the 1970s. This chal- the U.S. food system and lenge was met in a spectacu- greater understanding of lar way by the development ingredient functionality of commercial processes for helped create new products the -catalyzed and new markets. Food isomerization of glucose industry recognition that (dextrose) to the sweeter liquid sweeteners (syrups) sugar, fructose (levulose). offer ease of handling and Subsequent development of facilitate blending to meet separation processes for functional specifications enriching the fructose con- increased the popularity of tent not only allowed pro- corn sweeteners and steadily duction of syrups with expanded their usage. higher fructose content than could be produced by enzy- During the first half of the matic action alone, but ulti- 20th century, tech- mately allowed the manufac- nology advanced signifi- ture of pure crystalline cantly with the introduction fructose from starch. of enzyme-hydrolyzed prod- ucts. This allowed increased Isomerization technology control over syrup identities enabled the industry to pro- and properties. Two signifi- duce both of the simple sug- cant products were intro- ars that make up and duced that expanded the thus substantially match versatility of corn sweeten- total invert syrup (the prod- ers. The first was the intro- uct of partial or complete duction in 1921 of crystalline sucrose hydrolysis). The

5 resulting product, high fruc- the areas of fermentation, tose corn syrup (HFCS), was microbiology and carbohy- a development of profound drate chemistry has enabled significance for the food the industry to branch into industry and the U.S. markets traditionally served economy. Syrups of virtu- by chemical manufacturers ally any combination of and firms specializing in viscosity and sweetness as food additives. Pure strains well as other functional of produced through specifications could now be chromatographic separation produced from corn starch. combined with the enzyme technology developed to The availability of these produce HFCS opened a products made the U.S. new line of products to corn nearly self-sufficient in its refiners. Polyhydric sweetener supplies, provided , or , can be a major new market for economically produced via America’s corn producers catalytic hydrogenation of and created thousands of dextrose followed by chro- new permanent jobs in the matographic separation. corn refining and allied in- Heretofore, production of dustries. polyols was dominated by the chemical industry, The technology that allowed which used dextrose base the production of high qual- material supplied by corn ity HFCS has been utilized refiners. Polyols produced for the production of pure by corn refiners today in- fructose. Pure fructose, gen- erally supplied in crystalline clude erythritol, hydroge- form, is twice as sweet as the nated starch hydrolysates, dextrose from which it is , , isomerized; it provides eco- and . nomic and functional prop- erties that are being utilized The most recent addition to by all facets of the food in- the list of nutritive sweeten- dustry today. The develop- ers made by corn refiners is ment of crystalline fructose . Trehalose is a has made corn sweeteners a reduced sweetener viable alternative or comple- produced from starch ment to sucrose in the many through a series of enzy- products that require a dry matic conversions. It is a sweetener. chemically stable, non-re- ducing . Corn refiners’ expertise in While polyols and trehalose

6 are classified as nutritive Application of these prin- sweeteners, they are typi- ciples enables the industry cally referred to as alterna- to offer the purest, most tive sweeteners and have a consistent and most versatile lower caloric value than selection of sweeteners ever other corn sweetener prod- available. Today’s corn ucts. Detailed information sweeteners are also the most on the properties and uses economical natural sweet- of alternative corn sweeten- ener available. ers may be found on the Internet sites of individual producers. A listing of firms producing alternative The corn crop that provides sweeteners from corn may the starch for corn sweeten- be found on the Corn Re- ers represents the corner- finers Association Internet stone of American agricul- site (www.corn.org) under ture: around 10 billion GROWTH, the “Member Companies” bushels of corn are grown in DEVELOPMENT section. the United States each year. AND DIVERSITY During the last 30 years the corn refining industry has TECHNOLOGY AIMED used an increasing percentage AT NEEDS of this crop, and over the last The consumer-oriented five years has used about 14 technological development percent of all corn produced of new corn-derived prod- in the United States. In ucts continues to direct the 2005, corn refiners used ap- industry’s growth as well as proximately 1.5 billion bush- its potential for service to els of corn. The growth rate its customers. The ex- of corn sweeteners has been panded variety of corn most impressive. From 1960 sweeteners now available through 2005, while the per from the industry repre- capita annual use of nutritive sents an outstanding ex- sweeteners in the U.S. rose ample of the fruits of indus- from 112 to 143 pounds, the trial research and corn sweetener market share development aimed at rec- rose from 11 to 54 percent. ognized consumer needs. The curve shown in Figure 1 illustrates this growth since Corn refiners have applied the beginning of data collec- the principles of continuous tion in 1910-1913. Of par- quality improvement to ticular interest is the in- development of new sweet- creased growth since the ener products and processes. introduction of high fruc-

7 tose corn syrups that com- , higher sugars and pete directly with sucrose can be var- and sucrose-derived products ied to precise customer re- in the industrial market. quirements. These varia- tions reflect a diversity of While high fructose corn physical properties such as syrups represent a dramatic viscosity, breakthrough in sweetener content, osmotic pressure, technology, the corn refin- crystallization retardation, ing industry has also been gloss, humectancy, consis- sensitive to non-sweetness tency and many others val- functional requirements of ued by food and industrial its customers. The relative scientists. Process diversifi- amounts of various constitu- cation has added to the prod- ent sugars such as glucose, uct spectrum, as have blend- Figure 1 28 Corn Sweetener Shipments 26

24

22

20

18

16

14

12

10

Billions of Pounds - Dry Basis 8

6

4

2

0 1915 1925 1935 1965 1945 1955 1985 1995 1975 2005 Source: USDA

8 ing practices that allow mul- lar or powdery free-flowing tiple properties to be accen- semi-crystalline or amor- tuated. phous solid products compa- rable in chemical composi- This breadth of choice of tion to their liquid products and properties has counterparts. broadened the uses of corn sweeteners as industrial cus- Dextrose Monohydrate—is tomers have experimented purified and crystallized D- with both food and non-food glucose containing one mol- applications of starch con- ecule of water of crystalliza- version products. The var- tion per of ied uses of starch-derived D-glucose. conversion products are listed on pages 28 and 29. Dextrose Anhydrous—is puri- fied and crystallized D-glu- cose without water of crys- tallization.

Maltodextrin—is a purified concentrated aqueous solu- CLASSIFICATION tion of nutritive saccharides While numerous corn sweet- obtained from edible starch, eners from starch of widely or the dried product derived varying composition are from this solution, with a manufactured, commercial dextrose equivalence (DE) CLASSIFICATION products are organized into less than 20. AND seven broad classes for offi- cial designation and are de- High Fructose Corn Syrup—is NUTRITION fined accordingly. a purified concentrated aqueous solution of nutritive Corn Syrup ()—is saccharides obtained from the purified concentrated edible starch in which a por- aqueous solution of nutritive tion of the dextrose has been saccharides obtained from isomerized to fructose. It edible starch with a dextrose contains a minimum 42 per- equivalence (DE) of 20 or cent fructose on a dry basis. more. Fructose—is purified and Dried Corn Syrup (dried glu- concentrated D-fructose ob- cose syrup, corn syrup solids)— tained from edible starch is corn syrup from which the available in either anhy- water has been partially drous crystal or remelted removed, resulting in granu- liquid form. 2`11

9 Corn syrup, dried corn intake, particularly of starch, syrup, dextrose monohy- has decreased, the intake of drate and dextrose anhy- sugars has increased. drous are all the subject of Food and Drug Administra- The flexibility that corn tion (FDA) food standards sweeteners provide in for- codified in 21 CFR 168— mulating syrups containing Sweeteners and Table Sirups. almost any mixture of These definitions parallel simple sugars and higher those issued by the interna- polysaccharides is clear to tional Codex Alimentarius food scientists. The ability Commission. Maltodex- to incorporate sweetness of trins, dextrose, corn syrup almost any degree from corn and high fructose corn syrup sweeteners widens the range are Generally Recognized as of options for formulating Safe (GRAS) by the FDA. products to the requirements Specifications for corn of advancing carbohydrate syrup, dried corn syrup, nutrition. , dextrose, high fructose corn syrup and crys- The of carbohy- talline fructose may be drates begins in the mouth, found in the Food Chemicals with the action of salivary Codex published by the Na- on starch. Further tional Academy of Sciences. digestion of mono-, di- and Specifications for corn-de- polysaccharides is accom- rived sweeteners in pharma- plished through the actions ceutical use may also be of additional , many found in the U.S. Pharma- of which are located at the copeia/National Formulary. brush border epithelium of the small intestine (e.g., su- crase, lactase, , α- CORN SWEETENERS IN dextrinase). The monosac- NUTRITION charides, such as fructose, Current discussions of car- glucose and that bohydrates in nutrition result from the actions of point to an increasing role such enzymes, subsequently for corn sweeteners. There are absorbed into the blood has been a steady decline in stream and transported to the complex carbohydrate the liver or peripheral tis- content of the U.S. diet since sues for utilization by indi- before World War I and a vidual cells. After absorp- concurrent, offsetting rise in tion into an individual cell, consumption. Also, the is either while complex carbohydrate used directly for energy pro-

10 duction, stored as or sweeteners on glucose fat to meet future energy tolerance, melli- needs, or is converted to other tus, cardiovascular risk metabolic intermediates factors, micronutrient and needed for growth and/or trace mineral utilization, maintenance of body tissues. behavioral change and obesity. An extensive re- Free fructose availability in view of the nutritional the diet increased with the properties of fructose and introduction of HFCS 30 years fructose-containing sweet- ago. However, bound and free eners covered the same fructose availability from su- health issues and reached crose and invert sugar (hydro- similar conclusions. Re- lyzed sucrose) decreased at sults were published in nearly an identical rate, be- The American Journal of cause sucrose was displaced Clinical Nutrition (Volume from and beverages by 58, Number 5(S), Novem- HFCS. The dietary source of ber 1993). fructose has evolved—from fruit, to fruit-and-, to fruit-and-honey-and-sucrose, and finally to fruit-and-honey- and-sucrose-and HFCS—but the glucose:fructose monosac- CORN STARCH charide ratio remains un- Starch constitutes approxi- changed. Significantly, the mately 80 percent of the source of dietary glucose and and is the raw fructose is metabolically indis- material for all corn-de- tinguishable to the body rived sweeteners. It is TECHNICAL whether it originates from separated from other parts BACKGROUND fruit, honey, sucrose or HFCS. of corn by the corn wet milling process, illustrated Health and nutrition issues in Figure 2. Cleaned, concerning corn sweeteners shelled corn is soaked were evaluated by a special (steeped) in a battery of FDA task force in 1986. The tanks (steeps) in warm FDA concluded that consump- water containing 0.1 to 0.2 tion of corn sweeteners, other percent sulfur dioxide. than their contribution to the The steepwater swells and formation of dental caries, softens the grain to facili- posed no hazard to the general tate separation of the vari- public. Included in the FDA ous components. It flows review were extensive consid- counter-currently and is eration of the effect of corn ultimately drawn off and

11 replaced by fresh water. slurry is passed to a continu- Steeped corn is degerm- ous centrifuge for starch and inated in a starch-water () separation. slurry by passing it first The isolated starch fraction through a shearing mill is washed and concentrated which releases the germ and in a series of hydrocyclones then through a battery of to remove nearly all of the hydrocyclones that separate non-starch components prior the germ for oil extraction. to conversion to sweeteners. Figure 2 After fine grinding, the sepa- As with other cereal and The Corn Wet rated and hull root , corn starch Milling Process are screened to remove the occurs naturally in the form fiber (hull). The de-hulled of discrete granules of char-

Shelled Corn ○○○○○○○○○○

Corn Cleaners

Germ ○○○○○○ Centrifugal Hydroclone ○○○○○○○○○○○○○○○○○○○○○○○○○○○ Steep Tanks ○○○○○○○○ Grinding Mills Screens Separators Separators Starch Washing ○○○○○ ○○○○○○○○○○○○○○○ ○○○○○○○○○○○○

Steepwater Germ Fiber Gluten

○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○ ○○○○○○○○○○○ Germ Washing and Drying

○○○○ Refinery Clean, Dry ○○○○○ Germ

Oil Expellers Corn Germ and Extractors ○○○○○○○○○○Meal Starch Starch Crude Oil ○○○○○○○○○○○ ○○○○○○ Products Conversion Feed Products Products Oil Refining

Refined Corn Nutritive Sweeteners Oil Maltodextrins Corn Syrups Dextrose High Fructose Syrup High Maltose Corn Syrup ○○○○○○○ Corn Syrup Solids and other types

Low DEProduct Composition Flexibility High DE

12 Figure 3

LINEAR FRACTION ANHYDRO LINKAGE α-(1,4) GLUCOSE UNIT

BRANCHING BRANCHED FRACTION LINKAGE α-(1,6) acteristic size and shape. occurs in the α-(1,6) or iso- These granules swell when maltose linkage (see Figure 3). suspended in water and heated. Ultimately they For further discussion of the break apart to produce a manufacture and uses of paste with distinct rheologi- starch, see the booklet Corn cal properties in which two Starch published by the Corn molecular varieties of starch Refiners Association, Inc. are dissolved or dispersed in the medium. These molecu- STARCH HYDROLYSIS lar varieties are linear starch When the linkages between () and branched the condensed dextrose mol- starch (). In ecules (anhydroglucose corn starch, they occur in a units) in starch chains are ratio of about three parts of broken by the chemical addi- amylopectin to one part of tion of water, a reaction amylose. known as hydrolysis takes place. The ultimate product Both starch structures are of this reaction is a simple condensation homopoly- sugar called D-glucose or mers or multiple aggrega- dextrose. Starch hydrolysis tions of anhydroglucose may be catalyzed by both chemically acids and enzymes. bonded primarily in the α-(1,4) or maltose linkage. Acid-catalyzed hydrolysis While amylose is exclu- proceeds in a random fash- sively in the linear form, in ion. Depending upon the amylopectin, linear chains conditions imposed, stop- are organized in a tree form ping the reaction at any par- in which the branching point ticular time will yield a

13 product comprising predict- starch in very specific ways. able amounts of dextrose For example, β-amylase and of dextrose breaks the starch chain at smaller than starch. Thus, every other unit bond, pro- the hydrolyzate will include ducing optimal quantities of some dextrose, some maltose the disaccharide maltose (two dextrose units) some (two dextrose units). On the (three units), other hand, α-amylase some maltotetraose (four breaks the starch chain in units), and so on. Corn re- such a fashion as to produce finers have learned how to only minor amounts of low control this reaction by vary- and medium molecular ing temperature, time, cata- weight sugars but major lyst and substrate concentra- amounts of soluble higher tions so that fixed ratios of saccharides. these products are obtained consistently, thus insuring Glucoamylase, a third en- the uniformity and charac- zyme, hydrolyzes the starch teristic properties of various chains unit by unit, produc- corn sweeteners. ing large amounts of dex- trose in the hydrolyzate. The industry produces many types of syrups that are most Appropriate single or combi- simply identified by refer- nation processes employing ence to the “DE” value. The either acid catalysis alone, abbreviation DE stands for acid catalysis combined “dextrose equivalence,” de- with enzyme catalysis, or fined as a measurement of combinations of different the total reducing sugars in enzyme catalysis can pro- the syrup calculated as dex- duce almost any mixture of trose and expressed as a per- starch conversion products centage of the total dry sub- with chemical and physical stance. The method used to properties particularly determine dextrose equiva- suited to specific uses. lence is based on the reduc- ing action of - and -type sugars on spe- CRYSTALLINE DEXTROSE cific metallic salts (e.g., cop- Customers have always per sulfate in Fehling’s Solu- sought purer and sweeter tion). products. Manufacturers of corn sweeteners responded Enzymes, which are bio- by developing crystalline chemical catalysts, are used dextrose. Dextrose crystal- by the industry to hydrolyze lizes in two distinct forms:

14 at temperatures below 122 rated crystal when grown °F, monohydrate crystals from high purity solutions. are formed in which one molecule of water is bound DEXTROSE with each dextrose mol- ecule; at higher tempera- ISOMERIZATION tures, anhydrous dextrose Crystalline dextrose is quite crystals are formed. pure and finds many food and industrial uses, but it is Early attempts to produce a less sweet than sucrose. Al- high purity product required though this is an advantage either repeated crystalliza- in some applications, its tion steps or the use of non- reduced sweetness limits the aqueous solvents. The only use of dextrose, especially in solid forms of corn sweet- the production of carbon- ener available in quantity at ated soft drinks. To enter low price before 1920 were this market, a sweeter corn cast products. Starch was sweetener was needed. acid-converted to as high a DE as possible, refined and Naturally occurring sugars evaporated to a thick syrup, can generally be grouped and poured into molds into families, the members where it solidified. It was of which have the same em- then removed and ground pirical formula. In the hex- into small pieces. ose series (“ose” is the suffix which identifies a sugar) for The development in 1921 of example, in which dextrose a process for economically is the most common mem- crystallizing pure monohy- ber, all of the sugars have the formula C H O . All mem- drate dextrose resulted in a 6 12 6 rapid growth in dextrose bers of the group are isomers sales. Continued demand of one another. The main for increased purity led to differences between the development of anhy- isomers and the isomers in drous crystalline dextrose. other groups is in the nature Dissolving monohydrate of the reducing group crystals provides a pure (whether aldose or ketose) starting material. While a and in the spatial arrange- second monohydrate crystal- ment (stereo-chemical con- lization could be used to figuration) of the atoms (see produce a chemically pure Figure 4). product, it was found that the anhydrous form pro- The property of sweetness is duced a more easily sepa- directly related to the struc-

15 Figure 4 KETOSE (ketohexose) Hexose Sugars (C H O ) ALDOSE (aldohexose) 6 12 6

STEREOCHEMICHAL CONFIGURATION

D-glucose D-fructose

ISOMERIZATION

α-D-glucopyranose β-D-fructopyranose

D-glucose catalyst D-fructose

tural differences among the of an active isomerase en- . D-Fructose, a zyme to a dextrose-rich sub- ketohexose, has a relative strate. Later, however, batch sweetness in the range of 120 production was replaced by to 160 when compared to a a continuous process using sweetness standard value of reactors in which the 100 for sucrose. Dextrose (D- isomerase enzyme is immo- glucose) is an aldohexose bilized on an insoluble car- with a relative sweetness of rier. The production of 70 to 80 compared to su- HFCS in this manner was crose. The corn wet milling the first large scale use of an industry was therefore very immobilized enzyme sys- interested in a process tem. whereby D-glucose could be converted to D-fructose. The equilibrium conversion level of dextrose to fructose The enzymatic transforma- in this process is around 50 tion of glucose to fructose percent. However, econom- was introduced to corn ics dictate production at sweetener production in lower levels of conversion. 1967. The process, known as High fructose corn syrups isomerization, originally were first produced at a level involved the direct addition of around 16 percent fruc-

16 tose, but this was quickly fructose crystals from the boosted to 42 percent fruc- mother liquor. Both a dry tose. The 42 percent fructose version and a liquid fructose, syrup can be used in most produced by re-dissolving types of foods that make use crystalline fructose in water, of a liquid sweetener. are available.

A “second generation” high fructose corn syrup with higher levels of fructose was made possible by develop- ment of a fractionation pro- The manufacture of sweeten- cess that allows separation ers from corn starch is a of fructose from dextrose, multi-step process. The and subsequent concentra- starting point in the process tion of the fructose fraction. is the conversion of starch Standard formulations for slurry from the corn wet MANUFACTURE these products are 55 percent milling process to low solids fructose and 95 percent fruc- content syrup (liquor). The tose. The 55 percent syrup starch conversion process is has become the standard halted when the desired sac- sweetener for carbonated charide composition is beverages in this country, reached. The starch slurry is while the 95 percent fructose converted in either batch or syrup has wide application continuous converters. in many new and specialty foods. In addition, the avail- CORN SYRUPS ability of these higher (or The most common methods enriched) fructose syrups employed in the commercial has made possible the pro- production of corn syrups duction of pure fructose and are the acid process, the a new range of blended acid-enzyme process and the sweeteners that may be tai- multiple enzyme process. In lored for specific sweetening the acid-conversion process, and functional requirements a starch slurry of appropri- of food processors. ate dry substance is acidified to a pH of about 2 and Crystalline fructose is pro- pumped to a pressurized duced by concentrating the converter. The process is enriched fructose fraction terminated by reducing the obtained from the separation pressure and neutralizing the of high fructose corn syrups, resulting liquor. Small and then seeding, crystalliz- amounts of sodium chloride ing and separating the pure are produced by this neutral-

17 ization. The liquor is then cesses, starch granules are clarified to remove sus- gelatinized and the prelimi- pended solids and is evapo- nary starch depolymeriza- rated to an intermediate tion is accomplished by an concentration. The interme- α-amylase enzyme rather diate syrup is further clari- than by acid. fied, decolorized and finally evaporated to finished dry Various intermediate syrups substance. While carbon of differing composition treatment was the only refin- may be further converted ing method used for years, with enzymes having dis- many syrups are now treated tinctly different modes of with both carbon and ion- action to provide specific exchange resins for further products, such as high mal- refinement. tose syrups, high ferment- able syrups and others. The acid-enzyme process is similar except that the starch DRIED CORN SYRUPS slurry is only partially con- To produce dried corn syr- verted by acid to a given DE. ups (corn syrup solids), com- The “light liquor” is then pletely refined corn syrups treated with an appropriate are dried in spray or vacuum enzyme or combination of enzymes to complete the drum driers. This process conversion. For example, in forms granular, semi-crystal- the production of 42 DE high line or powdery amorphous maltose syrup, the acid-con- products. These are mildly version is halted at a point sweet in taste and moder- where dextrose production ately hygroscopic. Because is negligible. Then a mal- of the hygroscopicity, corn tose producing enzyme (α- syrup solids are packed in amylase, fungal α-amylase multiwall, moisture-proof or other) is added and the paper bags. Dried corn syr- conversion continued under ups are comparable in appropriate conditions to chemical composition to the desired level. The en- their liquid counterparts. zyme is then deactivated and the purification, clarification MALTODEXTRINS and concentration proce- Maltodextrins are produced dures are continued as in in the same manner as corn acid-converted syrup pro- syrups except that the con- duction. version process is stopped at an early stage to keep the DE In multiple enzyme pro- below 20. Both acid and

18 enzyme processes are used dextrose hydrate. in their manufacture. Refin- ing is conducted as with The moist crystals can be corn syrups. Maltodextrins redissolved in pure water to are less hygroscopic because produce liquid dextrose that of their lower monosaccha- is marketed at approxi- ride content and are usually mately 71 percent dry sub- spray dried to provide white stance. Liquid dextrose is free-flowing powders, also produced by passing packed in multiwall bags. refined hydrolyzate through separation columns that DEXTROSE retain dextrose while allow- MONOHYDRATE ing higher saccharides to The manufacture of dextrose pass through the column. involves as complete depoly- The enriched dextrose con- merization of the starch sub- tent fraction is flushed from strate as possible and the the columns with deionized recovery of the product by water in a process similar to crystallization. Starch slurry that used for fructose enrich- is gelatinized as in the manu- ment. facture of corn syrup and is partially converted by acid DEXTROSE ANHYDROUS or α-amylase. Then a puri- Anhydrous dextrose is usu- fied glucoamylase enzyme is ally produced by re-dissolv- added to this intermediate ing dextrose hydrate and substrate to effect the con- refining the resulting dex- version to dextrose. trose solution. This solution is evaporated to very high The resulting liquor is con- solids content, and anhy- centrated, refined, cooled drous α-D-glucose is crystal- and pumped to crystallizers lized on induced or added where dextrose monohy- crystals at elevated drate crystallizes from the temperatures. The anhy- mother liquor under care- drous dextrose is separated fully controlled conditions. by centrifugation, washed It is separated and washed in and dried. centrifuges. The moist crys- tals are then dried in con- tinuous driers to about 8.5 HIGH FRUCTOSE percent moisture. The CORN SYRUPS mother liquor can be re- In the manufacture of high cycled and crystallized to fructose corn syrup, dextrose produce a second crop of solutions or high DE sub-

19 strates produced by dual systems relying on a simu- enzyme processes (α-amy- lated moving bed model are lase plus glucoamylase or α- utilized for this separation amylase plus glucoamylase/ process. The enriched fruc- pullulanase) are refined by tose fraction is generally carbon and ion-exchange recovered at an 80 to 95 per- systems and further treated cent purity. This product is enzymatically with a puri- blended with the 42 percent fied isomerase. The fructose feedstock to pro- isomerase reactors use an duce a commercial product immobilized enzyme system with 55 percent fructose enabling continuous isomer- content. After blending, the ization and extending the life syrup is refined again with of the enzymes. Isomeriza- both carbon and ion ex- tion is usually carried to a change systems and is evapo- point where the substrate rated to a dry solids level of contains 42 percent fructose. 77 percent. The enriched Following this step the prod- fructose fraction may also be uct is refined again through refined and evaporated sepa- carbon and ion exchange rately for sale to users who systems and is evaporated to desire a product with very a dry substance of 71 per- high fructose content. cent.

In the production of syrups FRUCTOSE with a fructose level above Pure fructose is produced by 50 percent, the original 42 concentrating the enriched percent fructose feedstock is fructose fraction obtained passed through separation from the separation of high (fractionation) columns that fructose corn syrups, and retain fructose while allow- then seeding, crystallizing ing dextrose to pass through and separating the pure fruc- the column. This is made tose crystals from the possible because of the natu- mother liquor. The dry ver- ral affinity of fructose for sion of the product is gener- divalent calcium immobi- ally supplied at a maximum lized on the column. Fruc- moisture content of 0.2 per- tose retained in these col- cent. A liquid fructose may umns is flushed from the also be produced by re-dis- system with deionized wa- solving crystalline fructose ter, while the dextrose is in water to a clear, colorless recirculated for further product of approximately 77 isomerization. Continuous percent dry substance.

20 The chemical, physical and Though the ‘type’ designa- functional properties of corn tion has largely fallen into sweeteners vary according to disuse, the classification of their composition. To facili- corn syrups by DE remains tate functional identity des- useful today, since syrups ignation, corn syrups used to within classes share certain GENERAL be classified into four types physical and functional CHARACTERISTICS (Types I-IV) on the basis of properties. dextrose equivalence (DE). Fructose-containing prod- Type I 20 DE - 38 DE ucts are not classified ac- Type II 38 DE - 58 DE cording to DE. Rather, they Type III 58 DE - 73 DE are identified by their fruc- Type IV 73 DE and above. tose content (i.e., 42%, 55%,

Table I Saccharides, Carbohydrate Basis Compositional Data Designation Ash DP1 DP2 DP3 DP4+ 28 DE 0.3 8 8 9 75 36 DE 0.3 14 12 11 63 34 HM (a) 0.3 9 34 24 33 43 HM 0.3 8 33 19 40 43 DE 0.3 19 15 12 54 43 DE 0.03 19 14 12 55 Ion Exchanged 53 DE 0.3 28 20 10 42 63 DE 0.3 36 31 11 22 63 DE 0.03 36 31 13 20 Ion Exchanged 66 DE 0.3 40 35 8 17 95 DE 0.3 96 2.5 0.5 1 95 DE 0.03 96 2.5 0.5 1 Ion Exchanged HFCS 42 0.03 96 2.5 0.5 1 HFCS 55 0.05 96 2.5 0.5 1 HFCS 95 0.03 99 Crystalline 0.05 100 Fructose

(a) high maltose DP = Degree of polymerization n DP = (dextrose, dextrose + fructose in HFCS, 1 fructose in crystalline fructose) DP = , primarily maltose 2 DP = , primarily maltotriose 3 DP = , maltotetrose and higher saccharides 4+

21 95%, crystalline). Crystal- Several generalizations con- lized fructose is available in cerning the composition of several particle sizes, from various syrups can be made. powder to very large granu- 20-38 DE (Type I) corn syr- lations. Maltodextrins are ups and maltodextrins con- not classified in differing tain relatively small concen- ranges, but are produced in a trations of low molecular range of DE values, all be- weight saccharides such as low 20. dextrose, maltose and maltotriose. 58-73 DE (Type CARBOHYDRATE III) and 73+ DE (Type IV) COMPOSITION corn syrups contain rela- In order to evaluate the func- tively small concentrations tionality of individual syr- of the higher molecular ups, the actual carbohydrate weight oligosaccharides composition is most useful. above maltoheptaose. 38-58 Such information is best DE (Type II) syrups have obtained by high perfor- mixed compositions depend- mance liquid chromato- ing on the hydrolysis pro- graphic (HPLC) analysis. cesses used and the extent of Typical carbohydrate com- conversion. Acid and acid- positions of major commer- enzyme processes will pro- cially available corn syrups duce products of different are shown in Table I. saccharide composition, and

Figure 5 60 Acid Hydrolyzed Corn Syrup Analysis 50

40 Dextrose Higher Saccharides

30

Percent Constituent Percent Maltose 20

10 Tri & Tetra Saccharides

25 30 35 40 45 50 55 60

22 50 Figure 6 Acid-Enzyme Hydrolyzed Corn 40 Dextrose Syrup Analysis Maltose 30

Tri & Tetra 20 Saccharides Percent Constituent Percent

10 Higher Saccharides

40 45 50 55 60 65 70 Dextrose Equivalent are depicted graphically in cent dextrose and 14 percent Figure 5 and Figure 6. In maltose. A 43 DE (Type II) these graphs, composition is high maltose syrup may plotted against DE so that contain about 9 percent dex- the saccharide distribution trose and 43 percent maltose. can be read from the chart. SOLIDS CONTENT Other than describing the In addition to the carbohy- syrup by DE alone, it is fre- drate composition, corn quently useful to state the syrups are also characterized composition in terms of DE according to solids content. and one or more of the sac- In the past, commercial corn charide fractions. A good syrups were customarily example of this is 43 DE high sold on a Baumé (Bé) basis, maltose type syrup made by an indirect measure of the an acid-enzyme process. In dry substance content calcu- this case, a partially acid- lated from direct measure- converted corn syrup is ment of specific gravity. treated with β-amylase to Though still sold on this produce syrup having a basis, analytical determina- greater maltose concentra- tions of solids content are tion with a minimal amount today made largely by direct of dextrose. The regular 43 measurement of refractive DE (Type II) acid-converted index (RI). (Abbreviated syrup contains about 19 per- tables of refractive index/

23 dry substance relationships centration is evident when for commercial products are dextrose solutions are com- provided on pages 32-33.) pared with sucrose solu- The solids content of the tions. A 2 percent water more recently developed solution of dextrose is about high fructose corn syrups is two-thirds as sweet as a su- measured by refractive index crose solution of equivalent and stated as dry substance, concentration. As the con- without reference to Baumé. centration is increased, the difference in sweetness be- A computer program called comes less apparent. RI-DS, available from Corn Refiners Association, Inc., Corn syrups also impart will generate detailed tables greater sweetness at higher of dry substance, refractive concentrations. On a rela- index, commercial Baumé, tive scale of sweetness, fruc- specific gravity, pounds per tose is sweeter than glucose, gallon and dry substance per which in turn is sweeter than gallon for corn sweeteners of maltose, and maltose is known saccharide composi- sweeter than higher saccha- tion. rides. Since the mono- and di-saccharides also have a Most corn syrups are avail- higher reducing power (DE), able in the range of about 77 the DE value of corn syrups to 85 percent dry substance. provides an indicator of rela- HFCS-42 (42 percent fruc- tive sweetness differences tose) and high dextrose syr- among the four major types. ups are usually supplied at High fructose corn syrups about 71 percent dry sub- are similar to sucrose in stance. HFCS-55 (55 percent sweetness when compared fructose) and liquid fructose on a dry substance basis, are supplied at a 77 percent while crystalline fructose is dry substance. sweeter than sucrose.

SWEETNESS Solutions made from crystal- All corn sweeteners have a line fructose are nearly 1.5 clean, pleasant, sweet taste. times as sweet as sucrose in The sweetness of corn syr- 2 percent solutions. As con- ups is dependent upon the centration increases, the concentration of sweetener sweetness of fructose relative and the combination of sac- to sucrose declines and be- charides. comes relatively constant at 1.2 times the sweetness of The effect of increasing con- sucrose at concentrations of

24 10 percent and above. feel. The sweet taste of corn sweeteners, especially fruc- When corn syrup, HFCS, tose-containing syrups and dextrose or fructose is used crystalline fructose, is per- in combination with sucrose, ceived more quickly than the resulting sweetness is sucrose. These products usually greater than ex- provide a “non-masking” pected. For example, when source of sweetness that tested at 45 percent solids, a allows other food to mixture of 25 percent 42 DE be perceived more intensely corn syrup and 75 percent than similar products sweet- sucrose is considered as ened with sucrose. sweet as a sucrose solution of 45 percent solids. Hence, Function and sweetness of- when corn sweeteners are ten vary in a parallel way. used with sucrose in prod- Manufacturers of ucts having a relatively high find that body and texture total sweetener concentra- are both improved, for ex- tion, no apparent loss of ample, through the use of sweetness results. corn sweeteners, and that a smoother product, with less Sweetness is influenced by “meltdown,” and more resis- temperature, acids, salts and tance to “heat shock” results. flavoring materials as well as In sherbets and ices, these other factors. It is difficult, sweeteners provide optimal therefore, to state quantita- sweetness and also tend to tively the relative sweetness eliminate crystallization and of syrups and sugars in food promote smoothness. formulations. Each formu- lated product needs to be considered individually.

Corn sweeteners are thor- oughly compatible with other carbohydrate sweeten- PHYSICAL PROPERTIES ers and with food flavors. The physical properties of They are widely used in corn syrups, high fructose blends with other sweeten- corn syrups, dextrose and ers. In canned fruits, a liquid fructose are particularly PROPERTIES packing medium containing important in describing their HFCS and a 63 DE corn functional capabilities in AND USES syrup achieves optimum food and beverage products. sweetness while providing In the many examples listed superior gloss and mouth- in Table II, the indicated use

25 frequently reflects the func- groscopicity increases as the tional characteristic of the DE increases, since hydra- end product to which the tion is related chiefly to the corn sweetener contributes. monomer content. Corn syrups and dextrose are em- SOLUBILITY ployed as moisture condi- Solubility is one of these tioners, food plasticizers, properties. All corn sweet- crystallization inhibitors eners are readily soluble in and stabilizers. Fructose water. Corn syrups, for ex- serves as a in low ample, are aqueous solutions or intermediate moisture of starch conversion prod- foods. ucts containing about 80 percent dissolved solids at TEXTURAL room temperature. CHARACTERISTICS The presence of higher sac- Dextrose, another example, charides gives corn syrups has a negative heat of solu- their cohesive and adhesive tion; that is, it exhibits a properties. They contribute cooling effect when dis- to the body and fullness of a solved in water. This prop- product. The higher saccha- erty is useful to bakers since rides also contribute a it helps to control fermenta- chewy textural characteristic tion rates in raised to various types of confec- products. tions as well as to chewing gum. Anhydrous dextrose melts at 144° C, while dextrose hy- Blends of nutritive sweeten- drate melts at 82° C and ers offer unusual flexibility readily liquefies in a boiling to formulators in controlling water bath. Crystalline fruc- crystallization of certain tose will melt between 102° sugars, thus widening the C and 105° C. Dried corn temperature range of their syrups (corn syrup solids) utility. Moreover, the mois- gradually soften and dissolve ture holding capacity of in their own moisture (deli- some sugars contributes to quesce) when heated. the non-drip character of products such as hard can- HYGROSCOPICITY dies and . Corn sweeteners are hygro- scopic—that is, they readily All of the corn sweeteners, absorb moisture—to varying particularly the corn syrups, degrees. The extent of hy- control the crystallization of

26 other sugars and increase increased final viscosities. their solubility. This prop- erty is most advantageous in MOLECULAR PROPERTIES products such as ice cream, Dextrose and fructose are frozen , jams, jellies monosaccharides of molecu- and preserves. lar weight 180—half that of the disaccharide, sucrose. Corn sweeteners contribute They have a relatively high substantially to the attrac- osmotic pressure that en- tiveness of many foods. hances their effectiveness in They are widely used in inhibiting microbial spoil- combination with sucrose age. Corn syrup of 53 DE by the fruit canning indus- has about the same average try. The glossy appearance molecular weight as sucrose and syrup drainage control or and hence, about of fruits canned with cover the same osmotic properties syrups containing a corn as these sugars. Corn syrups sweetener is particularly of lower DE have higher pleasing to the consumer. molecular weights with cor- Corn syrups also improve respondingly lower osmotic the gloss and clarity of hard pressures. , jams and jellies. The effect of corn syrups Different nutritive sweeten- and sugars on the freezing ers affect water availability points of solutions is impor- or “mobility” differently. In tant in the manufacture of general, increasing the ice cream and frozen des- monosaccharide content serts (see Figure 7). The re- will increase the starch past- duction of the freezing point ing temperature, peak viscos- of a solution is inversely ity and gel strength. proportional to the molecu- Monosaccharides such as lar weight of the dissolved fructose and dextrose are solids. Generally, 20-38 DE more effective in increasing (Type I) and 38-58 DE (Type peak viscosities than are II) syrups depress the freez- disaccharides such as su- ing point somewhat less than crose and maltose. Com- an equal weight of sucrose. pared to starch/sweetener 58-73 DE (Type III) corn systems containing sucrose syrups have about the same or dextrose, systems contain- effect as sucrose on the freez- ing pure fructose demon- ing point. Dextrose, 73+ DE strate lower starch gelatini- (Type IV) corn syrups and zation temperatures and high fructose corn syrup

27 Table II: Applications of Nutritive Sweeteners Made From Corn Maltodextrins Glucose Syrups Dextrose HFCS Crystalline Fructose Maltodextrins Glucose Syrups Dextrose HFCS Crystalline Fructose Alcoholic Beverages, Brewing Building Materials Ale, llll Laminated l l Brandy l Wallboard l l Cordials l l l Canners & Packers Liqueurs l l Berries lllll l l l Fruits llll Animal Feed Fruit fillings llll llll Fruits, candied l l l l Cattle llll Fruit l l l Dog llll lllll Fish l Tomato sauces lllll Poultry l Vegetables l l Sheep and goats l Cereals Swine l Cereals lllll , Snack Foods Chemicals Baking powder l Acetic acids l l l Biscuits lllll l l l and rolls llll Coatings (food and drug) lllll Cakes lllll Cosmetics color l l l Drugs llll Cookies lllll Enzymes l l l Crackers lllll Fermentation processes llll Doughnuts lllll Food acids l l l Extracts and flavors llll Industrial l l Food coloring l l Insecticides l l Frosting, icing, glazes lllll Intraveneous solutions l Pies lllll Lecithin l l l Potato chips l ll Medicinal syrups llll l l l Organic solvents llll Pretzels lllll Pharmaceuticals l l l Spices l l l l l l Yeast l l l Condiments Beverages, Non-Alcoholic Catsup llll Carbonated lllll Gravies lllll Fruit drinks and juices lllll Mayonnaise lllll Powdered mixes lllll Mustard l l l

28 Maltodextrins Glucose Syrups Dextrose HFCS Crystalline Fructose Maltodextrins Glucose Syrups Dextrose HFCS Crystalline Fructose Oriental sauces lllll Chicken products llll Pickles, pickle products llll Dried lll Relishes lllll Fish, seafood lll Salad dressings lllll Hams lll Sauce mixes lllll Hot dogs lll l l l Mincemeat llll Worcestershire sauce l l l Sausage lll Surimi l Chewing gum lllll Miscellaneous Foods Chocolates lllll Baby foods lllll Confectionery lllll Dietetic preparations lllll Licorice lllll Invalid feedings lllll lllll Peanut butter lllll lllll Precooked frozen meals lllll

Fats & Oils and coffee polish lll Margarine l Mixes, Prepared Pan coatings l l Cake mixes lllll Formulated Dairy Products Cookie, brownie mixes lllll spreads and foods ll ll mixes lllll Coffee whitener llll Dried foods lllll Condensed milk lll Eggs, frozen or dried llll Frozen cream l l Frosting, icing mixes lllll Ice Cream & Frozen Desserts Gelatin mixes lllll Frozen or lllll Ice cream or milk lllll Gravy mixes lllll Powdered mixes lllll Instant foods lllll Sherberts, water ices lllll Instant tea lllll Jams, Jellies, Preserves , waffle mixes lllll Fruit butters lllll Quickbread mixes lllll Jams lllll Seasoning mixes lllll Jellies lllll Soups, dried lllll Marmalade lllll Syrups & Sweeteeners Preserves lllll Chocolate, cocoa lllll Products Dessert toppings lllll Bacon lll Fruit and table lllll Bologna llll Low calorie sweeteners lllll Breakfast meats llll Soda fountain lllll

29 Figure 7 Freezing-Point 32.0 Relations of 31.1 30.2 Sweetening 29.3 42 DE Corn Syrup Solutions 28.4 27.5 26.6 25.7 6 24.8 3 D 23.9 E Sucrose D C Degrees F Degrees 23.0 e x o 22.1 tro rn s S 21.2 e y ru 20.3 p 19.4 18.5 0 10 20 30 40 50 Percent Concentration

contain substantial propor- the difference between the tions of monosaccharide and same syrup at 100° F (12,500 lower the freezing point to a centipoises) and a 53 DE greater extent. acid-converted corn syrup with the same density that Both corn syrup and dex- shows a viscosity of only trose are also used in the about 7,000 centipoises. The manufacture of ice cream to method of conversion also control sweetness and im- affects viscosity: at identical prove body and texture. DE values, acid-converted syrups are more viscous than VISCOSITY acid-enzyme syrups, which Viscosity, one of the most are thicker yet than syrups important physical proper- produced by enzyme-en- ties of corn syrup, is depen- zyme conversion. dent on density, DE and temperature. Viscosity de- HFCS-42 at 71 percent solids creases as DE and tempera- (its commercial concentra- ture are raised, but increases tion) exhibits viscosity char- with higher density. For acteristics as follows: at 60° example, a 43 DE, 43 Bé acid- F, 380 centipoises; at 80° F, converted corn syrup has a 152 centipoises; and at 110° viscosity of about 12,500 F, 55 centipoises. HFCS-55 centipoises at 100° F, but at its commercial solids only about 1,700 centipoises level of 77 percent exhibits at 140° F. The effect of DE viscosity characteristics as on viscosity is illustrated by follows: at 60° F, 1,800

30 centipoises; at 80° F, 600 saccharide content; the centipoises; and at 110° F, higher the DE, the higher the 120 centipoises. fermentability.

Liquid fructose, when sup- REDUCING plied at 77 percent solids, CHARACTERISTICS exhibits viscosity character- Dextrose and fructose, istics as follows: at 40° F, through their respective al- 6000 centipoises; at 60° F, dehyde and reducing 1700 centipoises; at 70° F, groups, have the ability to 950 centipoises; at 80° F, 530 combine with various nitro- centipoises; at 90° F, 360 gen compounds at elevated centipoises; at 100° F, 240 temperatures to produce centipoises; and at 140° F, 55 desirable “browning” reac- centipoises. tion products, many of which exhibit characteristic CHEMICAL PROPERTIES food flavors (the Maillard FERMENTABILITY reaction). This property Fermentability is an impor- makes corn sweeteners par- tant property of corn syrups ticularly useful in the manu- and dextrose, particularly in facture of caramel color, in the baking and brewing in- the promotion of crust color dustries. The lower molecu- in baking and production of lar weight sugars—primarily caramel . mono- and di- saccharides, glucose, fructose and mal- The individual component tose—are readily ferment- sugars of corn sweeteners able by yeast. The total are technically termed “re- fermentability of corn syr- ducing” sugars. This “reduc- ups is roughly proportional ing” property aids in the to their mono-, di- and tri- inhibition of oxidative degra-

Table III Theoretical Observed Dextrose Equivalents Monosaccharide 100.00 100.00 of D-glucose and Disaccharide 52.6 58.0 its Polymers* 35.7 39.5 27.0 29.8 Pentasaccharide 21.7 24.2 Hexasaccharide 18.2 20.8

* Determined by Corn Refiners Association Analytical Method E-26

31 Table IV Refractive Index—Dry Substance Tables for Typical Corn Syrups

BÉ,COMM SP G TOTAL DRY SUB RI RI 140/60°F AIR/AIR LBS/GAL LBS/GAL %DS 20°C 45°C +1.0 100/60°F 100°F 100°F

28 DE 76.0 1.48881 1.48372 40.98 1.3929 11.60 8.82 77.0 1.49154 1.48643 41.49 1.3996 11.66 8.98 78.0 1.49429 1.48917 42.00 1.4064 11.72 9.14 79.0 1.49707 1.49192 42.51 1.4132 11.77 9.30 80.0 1.49986 1.49470 43.01 1.4201 11.83 9.46 36 DE 78.4 1.49377 1.48866 42.01 1.4065 11.72 9.19 79.4 1.49652 1.49139 42.52 1.4133 11.77 9.35 80.4 1.49929 1.49414 43.02 1.4202 11.83 9.51 81.4 1.50208 1.49692 43.53 1.4271 11.89 9.68 82.4 1.50489 1.49971 44.03 1.4340 11.95 9.84 34 HM (HIGH MALTOSE) 78.6 1.49330 1.48818 41.99 1.4061 11.71 9.21 79.6 1.49603 1.49089 42.49 1.4129 11.77 9.37 80.6 1.49878 1.49363 42.99 1.4197 11.83 9.53 81.6 1.50155 1.49638 43.49 1.4265 11.88 9.70 82.6 1.50434 1.49916 43.99 1.4334 11.94 9.86 43 HM (HIGH MALTOSE) 78.9 1.49337 1.48825 42.00 1.4063 11.71 9.24 79.9 1.49609 1.49096 42.51 1.4131 11.77 9.41 80.9 1.49883 1.49368 43.01 1.4199 11.83 9.57 81.9 1.50159 1.49642 43.51 1.4268 11.89 9.73 82.9 1.50437 1.49919 44.01 1.4336 11.94 9.90 43 DE 78.7 1.49330 1.48820 42.01 1.4065 11.72 9.22 79.7 1.49603 1.49091 42.52 1.4133 11.77 9.38 80.7 1.49878 1.49364 43.02 1.4201 11.83 9.55 81.7 1.50155 1.49639 43.52 1.4269 11.89 9.71 82.7 1.50434 1.49917 44.02 1.4338 11.94 9.88 43 DE (ION EXCHANGED) 78.8 1.49351 1.48840 41.99 1.4063 11.71 9.23 79.8 1.49624 1.49111 42.50 1.4130 11.77 9.39 80.8 1.49899 1.49385 43.00 1.4198 11.83 9.56 81.8 1.50175 1.49660 43.50 1.4266 11.88 9.72 82.8 1.50454 1.49937 44.00 1.4335 11.94 9.89 53 DE 80.5 1.49618 1.49107 42.64 1.4150 11.79 9.49 81.5 1.49890 1.49377 43.14 1.4217 11.84 9.65 82.5 1.50164 1.49650 43.64 1.4285 11.90 9.82 83.5 1.50440 1.49924 44.13 1.4354 11.96 9.98 84.5 1.50718 1.50201 44.63 1.4423 12.01 10.15 63 DE 81.0 1.49555 1.49045 42.53 1.4133 11.77 9.54 82.0 1.49823 1.49312 43.02 1.4200 11.83 9.70 83.0 1.50093 1.49581 43.52 1.4268 11.89 9.87 84.0 1.50366 1.49852 44.01 1.4336 11.94 10.03 85.0 1.50640 1.50125 44.50 1.4405 12.00 10.20

32 BÉ,COMM SP G TOTAL DRY SUB RI RI 140/60°F AIR/AIR LBS/GAL LBS/GAL %DS 20°C 45°C +1.0 100/60°F 100°F 100°F

63 DE (ION EXCHANGED) 81.3 1.49628 1.49118 42.61 1.4144 11.78 9.58 ` 82.3 1.49897 1.49385 43.10 1.4211 11.84 9.74 83.3 1.50168 1.49655 43.60 1.4279 11.89 9.91 84.3 1.50440 1.49926 44.09 1.4347 11.95 10.07 85.3 1.50715 1.50200 44.58 1.4415 12.01 10.24 66 DE 81.0 1.49486 1.48977 42.36 1.4111 11.75 9.52 82.0 1.49753 1.49243 42.86 1.4178 11.81 9.68 83.0 1.50021 1.49510 43.36 1.4246 11.87 9.85 84.0 1.50292 1.49779 43.85 1.4314 11.92 10.02 85.0 1.50565 1.50050 44.35 1.4383 11.98 10.18 95 DE 69.0 1.45977 1.45495 35.46 1.3237 11.03 7.61 70.0 1.46209 1.45726 35.96 1.3296 11.08 7.75 71.0 1.46443 1.45959 36.46 1.3356 11.13 7.90 72.0 1.46679 1.46193 36.96 1.3417 11.18 8.05 73.0 1.46916 1.46429 37.45 1.3477 11.23 8.20 95 DE (ION EXCHANGED) 69.0 1.45972 1.45491 35.40 1.3229 11.02 7.60 70.0 1.46205 1.45721 35.89 1.3288 11.07 7.75 71.0 1.46438 1.45954 36.39 1.3348 11.12 7.89 72.0 1.46674 1.46188 36.89 1.3408 11.17 8.04 73.0 1.46911 1.46423 37.38 1.3469 11.22 8.19 HFCS 42 69.0 1.45968 1.45425 N/A 1.3252 11.04 7.62 70.0 1.46200 1.45655 N/A 1.3311 11.09 7.76 71.0 1.46434 1.45886 N/A 1.3372 11.14 7.91 72.0 1.46669 1.46118 N/A 1.3432 11.19 8.06 73.0 1.46906 1.46352 N/A 1.3493 11.24 8.20 HFCS 55 75.0 1.47377 1.46799 N/A 1.3621 11.35 8.51 76.0 1.47619 1.47037 N/A 1.3683 11.40 8.66 77.0 1.47862 1.47277 N/A 1.3746 11.45 8.82 78.0 1.48107 1.47519 N/A 1.3808 11.50 8.97 79.0 1.48353 1.47763 N/A 1.3872 11.55 9.13 LIQUID FRUCTOSE 75.0 1.47322 1.46673 N/A 1.3639 11.36 8.52 76.0 1.47562 1.46909 N/A 1.3701 11.41 8.67 77.0 1.47803 1.47146 N/A 1.3763 11.46 8.83 78.0 1.48046 1.47385 N/A 1.3825 11.52 8.98 79.0 1.48291 1.47626 N/A 1.3888 11.57 9.14

*Refractive index is dependent on product composition, including saccharide profile and inorganic (ash) content. Actual refractive index values for individual products may vary slightly among producers. For precise dry substance determination, refer to product composition data and the computer program RI-DS, available from the Corn Refiners Association, Inc.

33 radation in foods. It is use- able from the Corn Refiners ful in maintaining the bright Association and the mem- red color of tomato catsup bers of the Association. and preserves and helps to retain the char- acteristic color of cured meats. This chemical reduc- ing action of syrups and There are countless methods sugars is also measured and for determining the chemi- expressed by dextrose cal and physical properties equivalence (DE). Table III of corn sweeteners. The shows the relative reducing Corn Refiners Association, power of various sugars. ANALYTICAL through its Quality Systems EXAMINATION Committee, has spent many The observed values repre- years developing and stan- sent a summation of a com- dardizing practical and effec- plex of chemical reactions. tive analytical procedures Therefore, precise condi- for corn starch and starch- tions must be maintained in derived products. The making a DE determination. Committee actively contin- DE values are not used to ues its work on standardiza- characterize high fructose tion of analytical procedures corn syrups. today.

PH VALUES OF The Corn Refiners Associa- CORN SYRUPS tion publishes these analyti- Corn syrups are finished cal procedures and makes and stored slightly on the them available at no charge. acid side. They are available These methods are pub- in a pH range of about 3.5 lished in Analytical Methods to 5.5. Because traditional of the Member Companies, pH measurement is difficult which is available from in ion-exchanged products Corn Refiners Association such as high fructose corn website at www.corn.org. syrup, acidity in these prod- By cooperation with the ucts is often measured by Association of Official Ana- titratable acidity or conduc- lytical Chemists, many of tivity. these methods are available through that organization’s Additional data on corn reference publications as derived sweeteners are avail- well.

34 Corn Refiners Association 1701 Pennsylvania Avenue, N.W. • Washington, D.C. 20006-5805 202-331-1634 Fax: 202-331-2054 • www.corn.org