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Abstract  

The DSC curve of freeze-dried amorphous sucrose shows the glass transition, the crystallization and the melting (just before decomposition) of the sample. Sucrose crystallization occurs below 100°C: this phenomenon can therefore be observed with the microcalorimeter Setaram Micro-DSC used in the scanning mode. Mixtures of amorphous and crystalline sucrose in known proportions were used to calibrate the instrument. Low level amorphism (down to about 0.5%) could be detected and quantitatively evaluated on the basis of the crystallization enthalpies determined. The calibration curve obtained can be applied to determine the degree of amorphism in milled sucrose. A simple gravimetric method, based on the desorption of water induced by recrystallization of the amorphous layer can be used to obtain similar data more rapidly. This simple method is particularly useful for controlling the amorphism on line during a process, and is also briefly described.

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El-Saka, M. M., Awad, A. E., Fahmy, B., Dowh, A. K. (1995): Influence of ethephon, silver thiosulfate and sucrose pulsing on bird-of-paradise vase life. Postharvest physiology, pathology and technologies for horticultural commodities. Proceedings

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The purpose of this study was to measure the effect of co-lyophilized polymers on the crystallization of amorphous sucrose, and to test for a possible relationship between the ability of an additive to raise theT g of a sucrose-additive mixture, relative to theT g of pure sucrose, and its ability to inhibit crystallization. Differential scanning calorimetry was used to measure the glass transition temperature,T g, the non-isothermal crystallization temperature,T c, and the induction time for crystallization,Q, of sucrose in the presence of co-lyophilized Ficoll or poly(vinylpyrrolidone) (PVP). The effect of these polymers on the crystallization of sucrose was significant as demonstrated by a marked increase inT c, and in the induction time (Q) in the presence of relatively small amounts (1–10%) of additive. Surprisingly, small amounts of polymeric additive had no effect on theT g of sucrose, although at higher concentrations, theT g increased proportionally. Thus, it appears that the inhibition of sucrose crystallization by the additition of small amounts of a higher-T g component cannot be attributed solely to changes in molecular mobility associated with an increase inT g.

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Abstract  

The relaxation map of highly concentrated sucrose water mixtures was built using mechanical and impedance spectroscopies. Data of - and -relaxation processes obtained with both techniques complete calorimetric and rheological measurements. The temperature evolutions of the relaxations were extrapolated using the measured data and the equations commonly used to describe the relaxations: Arrhenius and WLF behaviours for respectively the - and -relaxations. The temperature/frequency domain when and processes merge for 99% sucrose solution is discussed with respect to scenery proposed in the literature.

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SBA-15 silicas containing sucrose

Chemical, structural, and thermal studies

Journal of Thermal Analysis and Calorimetry
Authors:
M. Barczak
,
M. Oszust-Cieniuch
,
P. Borowski
,
Z. Fekner
, and
E. Zięba

either extraction with ethanol and acid or calcination at elevated temperatures. One of the scientific applications of SBA-15 silicas is their use as hard templates for the synthesis of ordered mesoporous carbons (i.e., CMK-3, CMK-5). Sucrose is

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compounds in the pear varieties during different harvesting stages is valuable for the utilisation of fruits for nutraceutical and processing industries. Soluble sugars like fructose, glucose, sucrose, and sorbitol are accountable for sweetness of fruit, and

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glutamate oxaloacetate transaminase GPT glutamate pyruvate transaminase SS sucrose synthase

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Dynamic and sub-ambient thermal transition relationships in water–sucrose solutions

Differential scanning calorimetry and neutron scattering analysis

Journal of Thermal Analysis and Calorimetry
Authors:
D. Champion
,
C. Loupiac
,
D. Russo
,
D. Simatos
, and
J. M. Zanotti

structural and functional alterations of these systems. The ability of sugars to preserve biomolecules during freezing has been recognized for years. The disaccharides most often described in literature for this aim are sucrose, maltose, and trehalose. This

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Perscitelli, S. M., Johnson, C. D., Petolino, J. F. (1990) Isolated microspore culture of maize: effects of isolation technique, reduced temperature, and sucrose level. Plant Cell Rep. 8 , 628-631. Isolated microspore culture of

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connection with the addition of such prebiotics to food products ( Picazo et al., 2019 ). FOS can be thought of as low molecular weight, non-viscous, water-soluble dietary fibers. Short-chain FOS can be produced by enzymatic synthesis from sucrose using

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