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Calculations of intermolecular interactions of D-fructose with the HyperChem avaible programs

100%

Mazurkiewicz J.

Polish Journal of Food and Nutrition Sciences

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1997

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tom 06

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nr 2

31-40

The energetically preferred isomer-conformers of D-fructose under vacuum and in aqueous solutions were determined involving the AMI and MM+ calculations, both available in the HyperChem program. Both methods were fairly compatible when the calculations of interactions under vacuum were considered. In aqueous solution, the calculations according to both methods were apparently not consistent with one another. However, the energetical differences which decide on the priority of certain isomer-conformers were almost negligible.

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Structure of aqueous D-fructose solutions

88%

Mazurkiewicz J.

Polish Journal of Food and Nutrition Sciences

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1997

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tom 06

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nr 1

99-106

Unusually low viscosity of aqueous solutions of D-fructose was attempted to be explain. The AMl-calculations were carried out for all isomer-conformers of D-fructose under vacuum and in aqueous solutions. Under vacuum, 2 α-D-Frup molecules formed the most stable pair, whereas in the aqueous solution the energetical preferences were found for the β-D-Frup-ß-D-Fruf pair. The differences in the energy for particular hydrated D-fructose isomer-conformer pairs, were within the order of energy available from the intermolecular collisions. Therefore, one could suggest that there would be practically a little chance for controlling rheology of aqueous D-fructose solutions. The energetical characteristics of the structures of D-fructose hydrates is given.

3

Saccharide-saccharide interactions under vacuum and in aqueous solutions

63%

Mazurkiewicz J.

Polish Journal of Food and Nutrition Sciences

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1997

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tom 06

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nr 4

35-40

Interactions between anomers of D-fructose and D-glucose, D-fructose and sucrose as well as D-glucose and sucrose in so-called computer vacuum and in aqueous solutions were recognized by means of the MM+ calculations. The strongest interactions were observed in the combinations of two ß-glucopyra- noses, α-glyucopyranose with α-fructopyranose and sucrose with ß-glucopyranose. Rheoiogical studies of aqueous solutions of the saccharide blends showed negligible differences in the viscosity for all tested combinations. The system of a lower calculated energy had a higher experimental viscosity.

4

Viscosity of aqueous solutions of saccharides

51%

Mazurkiewicz J., Nowotny-Rozanska M.

Polish Journal of Food and Nutrition Sciences

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1998

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tom 07

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nr 2

171-180

Concentration and temperature effects upon the viscosity of aqueous solutions of various mono- (D-glucose, D-fructose, D-fucose, L-rhamnose) and di-sac- charides (sucrose, maltose, lactose) as well as some of their two-component blends were recognized. Intrinsic viscosities determined for these solutions provided an insight into such details of the structure of solutions as structure of mers and bulk of the sugar hydrates. Parameters of linear equations <ƞ> = a c + b where <ƞ> and c are reduced viscosity and concentration, respectively, were determined. Irrespective of temperature (20, 40 and 60°C) and composition, the viscosity of aqueous solutions of disaccharide blended with monosaccharide significantly increased with concentration. However, the resulting viscosities were always lower than these for corresponding aqueous disaccharide solutions and higher than these for aqueous monosaccharide solutions. Viscosity of aqueous solutions of disaccharide blends were practically concentration independent.

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Walidacja enzymatycznej metody oznaczania zawartosci cukrow w napojach bezalkoholowych, niegazowanych

38%

Rybicka R.

Żywność Nauka Technologia Jakość. Suplement

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2002

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tom 09

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nr 3

159-169

Zgodnie z normą PN-EN ISO/IEC 17025:2000 [13], przed wprowadzeniem nowej metody do badań, laboratorium powinno potwierdzić, że jest w stanie prawidłowo ją realizować. Analizie poddano metodę enzymatyczną oznaczania zawartości cukrów w napojach stosując test enzymatyczny firmy Boehringer Mannheim. W pracy sprawdzono metodykę oznaczania zawartości D-glukozy, D-fruktozy i sacharozy w napoju bezalkoholowym, niegazowanym w oparciu o standardy dostępne w teście oraz przeprowadzono ocenę statystyczną metody. Na podstawie uzyskanych wyników stwierdzono, że powyższa metoda nadaje się do zastosowania w warunkach laboratorium.

Ograniczanie wyników

4 Polish Journal of Food and Nutrition Sciences

1 Żywność Nauka Technologia Jakość. Suplement

4 Mazurkiewicz J.

1 Nowotny-Rozanska M.

1 Rybicka R.

1 2002

1 1998

3 1997

Calculations of intermolecular interactions of D-fructose with the HyperChem avaible programs

Structure of aqueous D-fructose solutions

Saccharide-saccharide interactions under vacuum and in aqueous solutions

Viscosity of aqueous solutions of saccharides

Walidacja enzymatycznej metody oznaczania zawartosci cukrow w napojach bezalkoholowych, niegazowanych