Sugar 1-20 INDEX

Fructose—Dextrose Separation. Emctose—dextrose separation is an example of the appHcation of adsorption to nonhydrocarbon systems. An aqueous solution of the isomeric monosaccharide sugars, C H 2Dg, fmctose and dextrose (glucose), accompanied by minor quantities of polysaccharides, is produced commercially under the designation of "high" fmctose com symp by the enzymatic conversion of cornstarch. Because fmctose has about double the sweetness index of dextrose, the separation of fmctose from this mixture and the recycling of dextrose for further enzymatic conversion to fmctose is of commercial interest (see Sugar Sweeteners). 

The concentration of a pure sugar solution is determined by measurements of polarization (optical rotation), refractive index, and density. 

Refractive Index. The refractometric value of sugar solutions is used as a rapid method for the approximate determination of the soHds content (also known as dry substance), because it is assumed that the nonsugars present have a similar influence on the refractive index as sucrose. Measurement is usually carried out on a Brix refractometer, which is graduated in percentage of sucrose on a wt/wt basis (g sucrose/100 g solution) according to ICUMSA tables of refractive index at 20.0°C and 589 nm. Tables are available that give mass fraction corrections to refractometric values at temperatures different from 20°C. 

ICUMSA (1) has adopted tables showing the relationship between the concentration of aqueous solutions of pure sucrose, glucose, fmctose, and invert sugar and refractive index at 20.0°C and 589 nm. 

Hplc techniques are used to routinely separate and quantify less volatile compounds. The hplc columns used to affect this separation are selected based on the constituents of interest. They are typically reverse phase or anion exchange in nature. The constituents routinely assayed in this type of analysis are those high in molecular weight or low in volatility. Specific compounds of interest include wood sugars, vanillin, and tannin complexes. The most common types of hplc detectors employed in the analysis of distilled spirits are the refractive index detector and the ultraviolet detector. Additionally, the recent introduction of the photodiode array detector is making a significant impact in the analysis of distilled spirits. 

If the feed flows countercurrent to the air, as is the case when drying granulated sugar, exhaust temperature does not respond to variations in product moisture. For these diyers, product moisture can better be regulated by controlhng its temperature at the point of discharge. Conveyor-type diyers are usually divided into a number of zones, each separately heated with recirculation of air which raises its wet-bulb temperature. Only the last two zones may require indexing of exhaust-air temperature as a function of AT... 

There is also a fourth division of Beilstein (systems 4721 -4877) that covers natural products of uncertain structure rubbers, sugars, and so on. These are treated in vols. 30 and 31, which do not go beyond 1935 and which are covered in the collective indexes. These volumes will not be updated. All such compounds are now included in the regular Beilstein volumes. 

The anthocyanin stabilities of grape-marc, elderberry, and black currant extracts were lower in all sucrose (100 g/L)-added systems as compared to the controls at pH values of 3, 4, and 5, whereas the brown index did not change with the addition of sugar. On the contrary, a protective effect of 20% sucrose added to frozen crowberries and strawberries was reported and the stabilities of anthocyanin juices from aronia were higher in syrups than in diluted extracts. Roselles pre-... 

Sugar Association Inc., Washington, DC. http //www.dominosugar.com/dhtml/society/ index.html. 

Fig. 16.2 A 3-year on-farm comparison study in Switzerland where microbial activity in orchard soils (expressed as the ratio of microbial bound carbonmitrogen) was higher (low values indicate higher bacterial presence and activity) in organic (filled symbols) than in integrated (open symbols) managed orchards (same symbol shape = orchards in the same village), (a) A clear correlation between the Cmic Nmic ratio to phosphorus content of the fruit flesh was found which (b) in turn was correlated with the fruit quality index (including sugar and acidity content and fruit flesh firmness) P = phosphorus content of the fruit fresh in mg/kg dry matter.

Year and month of analysis Sugar (Brix) % bio vs. IP Malic acid (g/1) bio vs. IP Fruit flesh firmness bio vs. IP Quality index ) bio vs. IP Other parameters bio vs. IP... 

In the case of complex carbohydrates the glycemic index is a measure of how quickly the carbohydrate is broken down. An example is to compare potato starch and polydextrose. Both are polymers of dextrose but potato starch in the form of mashed potato is rapidly broken down and causes a surge in blood sugar, i.e. it has a high glycemic index. In contrast, polydextrose, which has the dextrose units linked 1 - 6, a link that is rare in nature, is only 25% metabolised and has a very low glycemic index. 

Procedure, for reducing sugars, 23 475 Laneth-5, cosmetic surfactant, 7 834t Langbeinite, 5 785t 20 627, 628 in chemical fertilizer, 20 629 screen analyses of, 20 629t Langelier saturation index (LSI), 26 142— 143... 

The refractive index also varies with the amount of substance in a mixture. Most often, refractive index is used to assess the concentration of sugar in wine, soft drinks, cough medicines and other preparations having relatively high concentrations of sucrose. Refractive index is also used to determine the concentration of alcohol in fermented products. For sucrose solutions the refractive index varies from 1.3330 (pure water) to 1.5033 when the solution contains 85% sucrose. This is an increase of approximately 0.0002 in the refractive index for each 0.1%... 

Why are sugar and alcohol content in foods commonly determined by refractive index determinations ... 

Small amounts of impurities have a significant effect on the refractive index. In fact, the refractive index for many binary mixtures changes linearly with concentration over a wide range of concentrations. A calibration curve of refractive index vs. concentration along with the refractive index of a sample can be used to find the concentration of a species in the sample. For example, the food and beverage industry uses the refractive index to find the concentration of sugar solutions. Table 15.1 lists several additional applications for refractive index. 

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