Evaporation beet juice

Beet extract is also used as a colorant. Extract is sold as either a concentrate prepared by evaporating beet juice under vacuum to a total soHds content of 40—60%, or as a powder made by spray-dryiag the concentrate. Both products usually contain ascorbic or citric acid as a stabilizer, and a preservative such as sodium propionate. On a dry-weight basis, beet extract typically contains between 0.4 and 1.0% betanin, 80% sugar, 8% ash, and 10% cmde proteia. 

In the initial stages of purification, sucrose is recovered in juice form by crushing cane stalks or by extraction of sliced sugarbeets (cossettes) with hot water. The resulting solutions are clarified with lime, then evaporated to thick syrups from which sugar is recovered by crystallization. The final syrup obtained after exhaustive crystallization of sucrose is known as molasses. Enhanced recovery of sucrose from beet molasses is accomplished by ion-exclusion chromatography, a process used in some sugar mills in the United States, Japan, Finland, and Austria. 

SC GARS—Most of our sugar comes from sugar beets or sugar cane. The juice is pressed out. cleared, filtered, and evaporated. The result is pure, white crystals of a sugar with the chemical name sucrose (CisHjjGh). 

Juice extracted from cane or beet undergoes further purification steps, including precipitation, absorption, crystallisation and evaporation, which remove nonsugars and progressively concentrate the sucrose solution. The final step is crystallisation of sucrose from the syrup. This mixture of sucrose and liquor, known as the massecuite , is then centrifuged, and the crystals are washed and dried to a moisture content of 0.02% w/w and stored (Beesley, 1990). 

The basic steps in the manufacture of beet sugar (Fig. 6.9) consist of (1) washing, (2) shdng, (3) diffusion, (4) juice purification, (5) evaporation, and (6) crystallization. 

Beet Sugar.—One ton of beets will give about IK ton of juice, having a density of from 7 to 8K°B6. The concentration is done in two stages, and triple- or quadruple-effect evaporators with a capacity of from 3 to 4 gal. per square foot are used for the concentration up to 27°B6. The Wellner Yelinek, Swenson and Kilby construction are the usual types. The final concentration up to 42°B. is done in single effects of the coil or Standard type, with a capacity of about 1 gal. per square foot. 

Sulfur dioxide is undesirable if the concentration is above a few parts per million. The delicate color of the fruit is impaired and in some cases the metal of the can is corroded. Direct consumption cane sugars produced by the sulfitation process are usually undesirable for canning but the supply is limited to one section of the country. Sulfur dioxide is used in processing beet sugars but not as a bleach as was the practice earlier in the industry. It is now recognized that a few parts per million of sulfur dioxide added before the evaporation of the thin juice act as an inhibitor to the nonenzymatic browning and result in a sugar with less than 1 p.p.m. of sulfur. In the same manner the starch-conversion producers have been able to eliminate the objectionable hydroxymethyl furfural, an undesirable side reaction product in starch conversion. 

Sugar beets are harvested in the fields, washed, and cut into small pieces. The beet chips are then soaked in water and pressed to extract the sweet juice in them. The juice is boiled and the liquid evaporated to obtain crystalline sucrose. The solid material remaining from this process can be used as animal feed. 

Bioethanol with the lowest cost is obtained by the evaporation through the membrane independently of the type of raw material for processing. Thus, when the bioethanol production from the sugar beet (cmde juice) by the azeotropic distillation was used, the production cost of 1 ton of bioethanol was USD 1447.5 ( 1.14 per 1 L), and when the evaporation through the membrane was used - 1378.2 ( 1.09 per 1 L) or decreased by 4.8%. 

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