Granulated sugar, particle sizes

Kovacova (1990) describes a method for the batch drying of fruit and vegetable pulp in a fluidized bed in which carrier particles (variously crystalline and caster sugar, dried skim milk, potato and wheat starch, apple powder, semolina or oat flakes), pre-moistened to a solids content of between 55% and 76%, are fed to a preheated fluidized bed and sprayed with the pulp to be dried. A product with a narrow particle size distribution and a uniform pulp content is claimed. Specific foods for which fluidized bed granulation has been used include potato puree (Zelenskaya and Filipenko, 1989) and granulated dried apple (Haida et al, 1994). 

Confectionery factories normally use sucrose in a number of forms (for examples of particle size and forms commonly used in different confectionery products see Tables 3.2 and 3.3) granulated, i.e. crystalline milled sugar, icing sugar and possibly a 66% sugar syrup (see also... 

Danfoss QueCheck Vision System performs a continuous analysis directly from the production line, typically at 0.5 s intervals. The final results of the measurement are available after 100-300 frames so that an equivalent sieve analysis is completed every 3 min. The particle size distribution is documented via an interface with database and printer. The material is fed in a fine stream, by means of a vibratory feeder, past a vision camera that calculates the size distribution as it falls. The system has been applied to measuring the size distribution of sugar crystals. Online image processing has also been applied to monitoring granule size distribution and shape in fluidized bed granulation [150]. 

Confectioner s sugar is not widely used in pharmaceutical formulations because the poor-flow characteristics prevent its use in direct-compression blends. However, confectioner s sugar is used when a smooth mouth feel or a rapidly dissolving sweetener is required, and when a milled/micronized active ingredient must be blended with a diluent of similar particle size for powders or wet granulations. 

Substances containing additions of PEG are suitable for moist and for dry granulation and also for the direct compression of tablets and sugar-coated tablet cores without prior granulation. PEGs 4000 and 6000 are available in powder form for dry mixing. The particle size distribution of PEG powders has been described... 

One of the characteristic differences between a solution and a heterogeneous mixture is the sizes of the particles composing each of them. Molecule-sized particles such as sugar molecules, with dimensions in the nanometer range, tend to form solutions. Particles such as cornstarch granules, with dimensions larger than micrometers, tend to form heterogeneous mixtures. 

Instantisation, in which the fluidized bed is responsible for a significant change to the structure and size of the granules, should not be confused with the use of an integrated fluidized bed drier immediately following spray drying. There are many descriptions in the literature of such processes a recent example of a novel application of this technique (Jha et al, 2002) is in the production of a shelf-stable powdered kheer mix, an Indian dessert which consists of a sweetened mixture of cooked partially concentrated milk and rice flour. This is spray dried, the particles are then dried in a fluidized bed and finally dry blended with sugar. 

Free Flow PTFE - Suspension pol nnerized PTFE (polytetrafluoroethylene) particles first undergo size reduction followed by granulation and drying which result in a free flowing powder. Free flow PTFE has a similar consistency to sugar contrasted with fine cut PTFE which resembles flour. 

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