Fructose preparation from sucrose

Isoglucose is an equilibrium mixture of glucose and fructose prepared from cornstarch. It is a substitute for invert sugar, which is a 1 1 mixture of glucose and fructose prepared from sucrose. Starch is a mixture of the glucose polymers amylose (39) and amylopectin (40). The former contains... 

Fructose, prepared from hydrolysis of sucrose and isomerization of glucose is used in the manufacture of candy, soft drinks, and other processed foods. As fructose is 124 percent as sweet as sucrose, substitution of fructose for sucrose in foods permits a reduction in the calorie content of a food. 

Deoxynojirimycin has been prepared from sucrose in 35% overall yield by successive treatment with triphenylphosphine-carbon tetrachloride, sodium azide and acid resin to give 6-azido-6-deoxy-D-glucose and 6-azido-6-deoxy-D-fructose in which the former could be converted to more of the latter by use of polymer supported glucose isomerase. Hydrogenation of the fructose derivative gave DNJ. ... 

Small amounts of fructose on the surface of anhydrous glucose crystals prepared from sucrose have been measured by selective dissolution, reaction with a modified diphenylamine reagent that is 147 times more sensitive to fructose than glucose, and spectro-photometric analysis at 640 An automated Elson-Morgan... 

Similar anomalous distributions are observed in other thermal product mixtures. A commercial soft caramel made by heating sucrose and 0.1% acetic acid to 160°C contained 18% of a mixture of di-D-fructose dianhydrides.94 fi-D-Fru/-1,2 2,1 - 3-D-Fru/(now assigned as a-D-Fru/-l,2 2,l -a-D-Fru/83), ot-D-Fru/-1,2 2,1 -p-D-Fru/(5), ot-D-Frup-1,2 2,l -0-D-Fnjp (4), ot-D-Fru/-l,2 2,1 - 3-D-Frup (1), and p-D-Fru/-l,2 2,3 - 3-D-Fru/ (2) were found in the ratio 4 12 1 6 2. The first three of these, constituting 68% of the mixture, are considered to be kinetic products. The authors commented on this, but did not offer any explanation. Notice, however, that the preparation of such commercial caramels commences with heating of an acidic aqueous solution of sucrose, which almost certainly results in hydrolysis. Hence, the final dianhydrides are probably derived from the reaction of fructose, rather than sucrose. 

Other compounds identified in caramels are di-D-fructose and poly(glycosyl) dianhydrides (DFAs). DFAs were found in caramels prepared from D-fructose, D-glucose, and sucrose. The analysis was done after derivatization as TMS (per-0-trimethylsilyl) derivatives or as TMS-oxime (per-O-trimethylsilyl oxime) by... 

The direct syntheses of D-glucosyl-L-sorboside from sucrose and L-sorbose and of sucrose from D-glucosyl-D-xyloketoside and D-fructose can be obtained in phosphate-free enzyme preparations.40 The reactions are ... 

High fructose syrups, prepared from starch, are commonly used instead of sugar. They are generally known as high fructose corn syrup (HFCS) containing 30 percent fructose, 35 percent glucose, and 6 percent higher saccharides. They are only 74 percent as sweet as sucrose, therefore more has to be used to achieve the same sweetness. 

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. 

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