Sucrose brittleness

Panned confections Sucrose Brittle texture (hard panned) Soft texture (soft panned)... 

The effect of mixing a brittle material like methenamine or sucrose with... 

The only large-scale application of sucrose ethers appears to be to use poly-(9-(hydroxylpropyl) ethers, generated by alkoxylation with propylene oxide, as the polyol component for rigid polyurethanes —sucrose itself gives only brittle ones—which are used primarily in cushioning applications. The structures of these products, that is, the positions at which sucrose is alkoxylated and then carbamoylated with diisocyanates, and the type(s) of cross-linking involved, are not well defined though. 

Brittle Rapid propagation of a crack throughout the material on application of stress, e.g., sucrose, mannitol, sodium citrate, lactose, and dicalcium phosphate. 

Frozen fixed tissue is sectioned in a cryostat also known as a microtome in a freezer. The tissue is fixed in 4% paraformaldehyde, rinsed, and then cryoprotected by infiltration in 20% sucrose in buffer with agitation overnight at 4°C (cold room). After 24 h the tissue blocks will sink in the solution, indicating that they are infiltrated. This infiltration step is critical. If skipped, the tissue will freeze with damaged cells and holes from ice crystals, and the resulting tissue sections on microscope slides will be brittle and might crack. The tissue must be fixed first to hold the cells in place, as cryoprotection and freezing without fixation will destroy the tissue. 

This reaction is of considerable importance in the candy industry for at least two reasons. First, fructose is sweeter than sucrose, so the same level of sweetness can be achieved with fewer raw materials if fructose is substituted for sucrose. Second, a mixture of fructose and glucose, called invert sugar, does not crystallize, so the candy containing this sugar would be chewy rather than brittle as candy containing sucrose crystals would be. (a) From the following data, determine the order of the reaction. 

Synthesis from sucrose ester, aluminium diiso-propoxide monoacetylacetonate and diisocyanate. In pre-liminary experiments, sucrose "penta"soyate or sucrose "penta" dehydrated castor ester reacted in toluene at IIQOC with an equimolar proportion of aluminium diiso-propoxide monoacetylacetonate. (The latter was prepared separately by reaction of equimolar proportions of aluminium isopropoxide and acetylacetone in refluxing toluene with elimination of 1 mole 2-propanol). The modified sucrose ester reacted with 1.1 mole toluene diisocyanate (the maximum without gelation) and dibutyl tin dilaurate as catalyst. The performance of air-dried or stoved coatings was similar to material derived by the mono-/diisocyanate route in terms of alkali resistance, but they were more brittle. 

In a modification of this approach, tractable resins also were produced using aluminium isopropoxide for blocking sucrose hydroxyl groups, prior to reaction with toluene diisocyanate. Coatings from this resin also tended to be brittle. 

When the sucrose esters were evaluated as modifiers for cellulose acetate butyrate, the crystal-producing compounds gave brittle and sometimes hazy or opaque films as they continued to crystallize, even in the presence of the cellulose polymer (Table II). On the other hand, the liquid esters performed as plasticizers for cellulose acetate butyrate, producing soft and tacky films at 50% modification. Because of this softening action, sucrose esters, forming low-viscosity liquids, were eliminated from commercial consideration. It also was estimated that these esters could not compete costwise with the commonly used, coatings plasticizers. 

A summation of some of the properties which may allow sucrose benzoate to be called a "unique modifier" are listed in Table VI. Although most have been mentioned previously, the gloss as well as clarity and lack of color obtained from the use of this material is outstanding. Its amorphous nature eliminates any concern about crystallization in the modified system. It has excellent hardness, but in many applications it needs to be plasticized because of its brittleness. 

The most suitable polyols are prepared via a coinitiator technique whereby optimal functionality (4-5), hydroxyl number (330-430), use viscosity (2,500 cps max) and reactivity are achieved. Comparative letbora-tory evaluations have shown that sucrose amine-based polyols are inherently more compatible with polymeric isocyanates than other polyols. They have also demonstrated excellent flow and demolding characteristics and produce hard but not brittle structural foams. 

In large-scale preparations of suppositories lactose may be added for another purpose. Sometimes a high dose analgesic suppository has a good structure, while a low dose suppository is brittle. In such case another suppository base may be used. More easily, the volume of the suspended active substance may be increased by adding lactose. This provides a good suppository too. In this case the lactose only acts as filler. Other fillers used in suppositories are sucrose and microcrystalline cellulose [8h],... 

The same opportunities therefore exist to custom-tailor the contents of the interior aqueous phase and oil phase to the particular requirements of the protein. An aliquot of the primary emulsion is added to a rotary vacuum flask. Sucrose, or another suitable lattice material, is dissolved in sufficient water and added to the flask. A typical ratio of sucrose to primary emulsion is 3 1 (sucrose primary emulsion, w/w). Vacuum is applied until a brittle foam is produced. 

Croquant serves generally as a filling for candy. It is made of molten sucrose, which has been at least partly caramelized, and ground and roasted almonds or nuts. It is occasionally mixed with marzipan, nougat, stable dairy products, fruit constituents and/or starch syrup. Croquant can be formulated to a brittle or soft consistency. 

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