Starch Syrup Derivatives

Proteins suffer due to cost and chemical reactivity, malto-dextrins and corn syrup solids due to a dearth of interfacial function, lipophilic starches due to labelling constraints (a marketing decision), and gum arabic due to cost, as well as intermittent supply deficiencies. An inexpensive, "natural", strongly surface active polymer with excellent water solubility and chemical inertness clearly has vast economic potential. Oxidized, hydrolyzed and/or glycoamine starch-based derivatives were examined as possible avenues for delivering this polymer. 

Fructose, a monosaccharide sugar, occurs naturally in honey and a large number of fruits. It may be prepared from inulin, dextrose, or sucrose by a number of methods. Commercially, fructose is mainly manufactured by crystallization from high-fructose syrup derived from hydrolyzed and isomerized cereal starch or cane and beet sugar. 

To recover the starch, the corn kernels, for example, are pealed and then dipped in sulfuric acid at pH 3.5-4 for 40 h at 125°C. The corn kernels softened in this way are then coarsely ground and the corn nucleus removed by floatation, whereby the starch particles sedimentate. Fiber components are filtered off and the starch particles are removed from the remaining protein solution by centrifugation. The recovered starch particles are then washed and dried. Sixty percent of the starch is converted to starch syrup or dextroses by partial hydrolysis. The remaining 40% is used in the food industry or in the textile, paper, or detergent industry, partially as derivatives such as starch acetate or hydroxyethyl starch. 

A clear, viscous, syrup produced by the hydrolysis splitting—of potato starch with heat and acids, or enzymes. It contains dextrins, maltotetrose, maltotriose, maltose, and dextrose (glucose). The amount of each depends upon the conditions and duration of the hydrolysis. Corn syrup, derived in the same manner from corn starch, is more common in the United States. 

The substantial amounts of this ketohexose are mainly prepared by base-catalyzed isomerization of starch-derived glucose, yet may also are generated by hydrolysis of inulin, a fructooligosaccharide. An aqueous solution of fructose—consisting of a mixture of all four cyclic tautomers (Figure 2.5), of which only the (3-D-pyranose ((3-p) form present to about 73% at room temperature is sweet — about 1.5 times sweeter than an equimolar solution of sucrose hence, it is widely used as a sweetener for beverages ( high fructose syrup ). 

Corn (maize) syrup is a sweetener derived from corn starch by a process that was first commercialized in the 1920s. Corn syrup is composed of glucose and a variety of sugars described as the maltose series of oligosaccharides. These syrups are not as sweet as sucrose, but are very often used in conjunction with sugar in confections and odier food products. 

Calendar year HFS Sweeteners Glucose syrup, b Dextrose Total Total caloric sweetenersb Starch-derived sweeteners share of total caloric sweeteners, %... 

The GRAS affirmation contained in 21 CFR, Section 184.1444, defines maltodextrins as non-sweet, nutritive saccharide polymers consisting of D-glucosyl units linked primarily with alpha-1,4 bonds and having a DE less than 20. The document has been modified to include maltodextrins derived from potato starch as GRAS.8 In 1992, more than 328 million pounds (149x 106 kg) of maltodextrins and com syrup solids were produced in the United States from various starch sources.9... 

Figure 21.2 General process flow for starch-derived sweeteners (corn/glucose syrups, high fructose syrups, dextrose, fructose, maltodextrins and syrup solids).7...

Physical properties of a syrup depend heavily on its carbohydrate profile. The carbohydrate profile, in turn, is determined by the type of conversion and the nature of the enzyme treatment (previously discussed). Table 21.2 gives typical DE and carbohydrate profiles of syrups in common production today. Because enzyme treatments can provide sweeteners with different carbohydrate profiles but the same DE value, it is usual to refer to a product using more than one descriptor, e.g. a 43 DE, high-maltose syrup. This issue becomes particularly important when addressing functional differences and applications of starch-derived sweeteners. 

The color of starch-derived sweeteners is often referred to as water white, but it is more meaningful to express color of syrup in terms of absorbance (optical density, Table 21.11).63 Typically, the color of commercial com sweeteners, particularly high-fructose and dextrose syrups, is expressed in absorbance measured against a reference standard of water at 450 nm and 600 nm, as shown in Figure 21.17.64... 

Starch-derived sweeteners provide a highly fermentable substrate for many industrial applications. The ability of yeast to ferment starch-derived syrups is directly... 

Starch-derived syrups are able to crystallize, depending on the type of carbohydrates present, the solids level and the temperature. This property can be used to advantage, as in the manufacture of hard candy, or can be one to be avoided, as in the case of... 

Commercial dextrins are specifically the oligomers of starch. White dextrins, so called because of their visual appearance, are produced from a 30-40% suspension under the mildest possible hydrolysis conditions (79-120°C for 3-8 h in 0.2-2% H2S04 or HC1). Yellow dextrins and British gums are the partial hydrolysates at higher time-temperature integrals. Maltodextrins, dextrose equivalent20 5-19, derive from controlled enzyme or acid partial hydrolysis of gelatinized corn starch. The 20-24 dextrose equivalent hydrolysates tire com syrups (Appi, 1991). 

The hydrophilic part of the alkyl polyglucoside is derived from a carbohydrate source, and raw material costs increase in the order starch/glucose syrup/glucose monohydrate/water free glucose while plant equipment requirements and hence cost decrease in the same order. 

Starch is hydrolyzed to produce a range of sweeteners, including syrups and crystalline products. The bulk of starch-derived sweeten-... 

Figure 4-18 Major Steps in Enzymic Starch Conversion. Source Reprinted from H.S. Olsen, Enzymic Production of Glucose Syrups, in Handbook of Starch Hydrolysis Products and Their Derivatives, M.W. Kearsley and S.Z. Dziedzic, eds., p. 30, 1995, Aspen Publishers, Inc.

There are several practical applications involving interactions between starch and saccharides. For example, starch-derived sugars are used as plasticizers for starch.956 Thus, the addition of potato starch to sugar syrup increases the solution viscosity to a level where it retains gas bubbles and is suitable for producing froths.957 Agaran, starch, and swollen Sephadex G-200 form a mixed support for zone electrophoresis.958 A plywood of improved strength resulted from the blending of an aqueous solution of... 

Cellulose and derivatives (CMC, MC, HPC, HPMC) Stffl h and derivatives (fractionated nylose, mnylopectin, modifred propylated, acetylated..., hydrolysed starch dextrins, maltodextrins, glucose syrups, pregelatinized starch)... 

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