Sugars sucrose, inversion

Polarimetric determination of the sucrose concentration of a solution is vaUd when sucrose is the only optically active constituent of the sample. In practice, sugar solutions are almost never pure, but contain other optically active substances, most notably the products of sucrose inversion, fmctose and glucose, and sometimes also the microbial polysaccharide dextran, which is dextrorotatory. Corrections can be made for the presence of impurities, such as invert, moisture, and ash. The advantage of polarization is that it is rapid, easy, and very reproducible, having a precision of 0.001°. 

The mineral constituents of the raw cane juice persist in the final molasses. The principal difference in relative amounts of these substances in molasses arises from the use of lime in defecation which causes an increase in calcium. Egyptian cane molasses solids contained 0.66% of titanium.181 The cations are believed to complex with the sugars and to thus inhibit the crystallization of sucrose, which latter is known to form compounds with inorganic salts, such as its well known compound with sodium chloride. Decationization of cane juice with ion exchange resins greatly reduces molasses formation but sucrose inversion is a concomitant problem.182... 

Crystallization. The filtered thick juice is now sent to the vacuum-pan for boiling. It is essential to use low temperatures (65 to 80°C) in this process to avoid sucrose inversion and caramelization. Pan boiling and crystallization practices are very similar to the same unit process in the sugarcane refinery described earlier for cane sugar. Crystallization is continued until the crystals have reached the required size. This mixture of crystals and mother liquor, known as massecuite, is discharged into a mixer tank and from there it is sent to centrifugal separators. In... 

Refined sugar (sucrose) can be converted to glucose and fructose by the inversion process. Ci2H220ii + H2O -------------------------> C6H12O6 + CfiHizOe... 

The acid-catalyzed inversion of sucrose can be monitored by measuring the angle of rotation a of plane-polarized light with time, since the rotation shifts from dextro in sucrose to levo in invert sugar. The following data were obtained on sucrose inversion at 30°C in 2.5 M formic acid. 

Refined sugar (sucrose) can be converted to glucose and fructose by the inversion process... 

Acid or enzymatic hydrolysis of sucrose, inversion, produces an equimolar mixture of n-glucose and n-fructose known as invert sugar. Invert sugar is used as a food additive substance, usually in the form of syrup (relative sweetness is 95-105% of saccharose sweetness). It also serves as a starting material for obtaining d-glucose and D-fructose, the sweeteners mannitol and glucitol and other substances. 

Reaction with Organic Compounds. Many organic reactions are catalyzed by acids such as HCl. Typical examples of the use of HCl in these processes include conversion of HgnoceUulose to hexose and pentose, sucrose to inverted sugar, esterification of aromatic acids, transformation of acetaminochlorobenzene to chloroaruHdes, and inversion of methone [1074-95-9]. 

Because alkali degradation of sucrose does not result in inversion products, in slightly alkaline solution (pH < 8.5), the loss of sucrose to invert sugar (glucose + fructose) is a consequence of the acid hydrolysis mechanism, which provides D-glucose and D-fructose for further alkaline degradation. 

Loss of sucrose due to inversion by bacteria during the time between crushing the cane and processing the juice is considered serious. A very conservative estimate places the annual loss for Cuba, if uncontrolled, at 75,000 long tons of sugar. This loss can be drastically reduced by spraying Steri-Chlor 4X into the juice immediately after extraction at the rate of 10 pounds per 1000 tons of cane. The practice is now common and offers a potential market for approximately 450,000 pounds of such a product in Cuba and probably at least that much in other areas. Demands in- the near future should approximate 250,000 pounds and eventually should approach a maximum of 1,000,000 pounds. 

Hydrolysis of sucrose yields glucose and fructose with specific rotations [q ]d + 52.5° and —92°, respectively, and makes the resulting mixture laevorotatory (—). This phenomenon of sucrose is called the inversion of sucrose, and the resulting mixture is known as invert sugar, which is the main component of honey, and is sweeter than sucrose itself. 

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