Sugar crystals

Continuous vacuum pans have been successhiUy developed for raw sugar crystallization, and are widely appHed in South Africa, AustraHa, South America, and the United States. Continuous crystallizers, developed for beet sugar manufacture, are being adapted for use in cane sugar factories. 

Fig. 6. The three-hoiling beet sugar crystallization scheme.

Sweetness is primarily a function of the levels of dextrose and maltose present and therefore is related to DE. Other properties that increase with increasing DE value are flavor enhancement, flavor transfer, freezing-point depression, and osmotic pressure. Properties that increase with decreasing DE value are bodying contribution, cohesiveness, foam stabilization, and prevention of sugar crystallization. Com symp functional properties have been described in detail (52). 

Sugar Processing. Dispersants are used in the production of cane and beet sugar to increase the time between evaporator clean outs. Typical scales encountered include calcium sulfate, calcium oxalate, calcium carbonate, and silica. Dispersants are fed at various points in the process to prevent scale buildup, which would interfere with efficient heating of the vessels. Only certain dispersants, conforming to food additive regulations, can be used, since a small amount of the dispersant may be adsorbed on the sugar crystals. 

In sugar mills a rapid separation of sugar crystals from molasses is achieved through the use of massecuite and centrifugal force. The motor drives a basket full of molasses which undergoes repeated cycles of operation, i.e. 

Ploughing of sugar crystals at very low speeds of 50 r.p.m. or so. This is achieved by a 48- or a 56-pole motor. A further reduction in speed is obtained by conventional electrodynamic or d.c. electric braking. 

Massecuite i.s used to form and then remove sugar crystals from molasses by a centrifugal technique. 

MASSECUITE A mechanical mixture of crystals in mother liquor (molasses or heavy syrup), produced in a vacuum pan. The suspension of sugar crystals in mother liquor produced during the early stages of crystallization. 

Hydrocolloid stabilizers are vitally important in the manufacture of sherbet and ices. The absence of larger amounts of milk colloids and the presence of larger amounts of water emphasize the need for proper stabilization. Stabilizers help to maintain a Arm body and smooth texture during manufacture, storage, and distribution. Bleeding and surface sugar crystallization are two problems related to crystal structure in sherbet and ices and are very closely associated with the use of the proper hydrocolloid stabilizer. 

Competition acts in crystallization from solution as well as from a melt. Thus, in crystallization of sugar from solution the hydrocolloid could bind sugar molecules and thereby hinder growth of sugar crystals. 

See also Sugar beets Beet sugar crystallization scheme,... 

Continuous vacuum filters, 16 657 Continuous vacuum pans, for raw sugar crystallization, 23 449 Continuous veno-venous hemodiafiltration (CWHD), 26 832... 

Thorium metal, 24 759-761 in alloys, 24 760-761 preparation of, 24 759-760 properties of, 24 760-761 reactions of, 24 761 Thorium nitrate, 24 757, 766 Thorium oxalates, 24 768-769 Thorium oxide, 21 491 Thorium oxides, 24 757, 761-762 Thorium oxyhalides, 24 762 Thorium perchlorate, 24 764 Thorium phosphates, 24 765-766 Thorium pnictides, 24 761 Thorium sulfate, 24 764 Thorium-uranium fuel cycle, 24 758-759 Thorocene, 24 772 Thorotrast, 24 775-776 3A zeolite. See Zeolite 3A Three-boiling beet sugar crystallization scheme, 23 463-465 Three-color photography, 19 233-234 3D models, advantages of, 19 520-521 3D physical design software, 19 519-521 3D QSAR models, 10 333. See also QSAR analysis... 

A notable feature of carbohydrate crystals is the absence (or small proportion) of water of hydration. As monosaccharides are hydrophilic and water-soluble, considerable deposition of water (association) in a sugar crystal may be expected. The absence of water from the crystal lattice of a sugar must, therefore, be explained by supposing that the sugar is able to form sufficiently strong and numerous hydrogen bonds without the involvement of molecules of water this has been observed, although there are some exceptions. 

Co crystallisation is mainly done from supersaturated sugar solutions [15]. Aggregated particles (of 3-30 pm) of sugar crystals are formed which entrap guest molecules. The sugars form an oxygen barrier, thereby extending the shelf life of aroma chemicals. The procedure is simple and inexpensive, because relatively cheap encapsulation matrices can be used, such as sucrose. 

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