US2610930A - Noncrystallizing corn sugar process - Google Patents

Description

Patented Sept. 16, 1952 UNITED ST T ENT F NONCRYSTALLIZING CORN SUGAR I PROCESS James antenna, Granite City, 111., assignor to Union. Starch. 8; Refining Company; Columbus, 11111., a corporation of Indiana No Drawing. Application April 27, 1946, Serial No. 665,646

This. invention relates to a liquid sugar or solution. of. sugar which .cannot be made toxcrystal- 3 Claims. (01.127 40) lize under conditionswhich would otherwise cause crystallization and methods of making the same. This process is novel in respect 'to starting materials', their condition and the principle utilized to achieve the results so that the product is also novel in a number of important respects.

Where the ultimate useof a sugar requires that the sugar be in a liquid or'dissolved state there are, many advantages of a non-crystallizing sugar over a crystalline product. A solid or crystallized sugar is ordinarily crystallized into billets, chipped, packed in bags, loaded and shipped to the consumer. Before dissolving or melting, the billets orchips must be unloaded manually. With non-crystallizing or liquid sugar, not only are the chipping and remelting steps eliminated but the cost of shipping bags, of loading and unloading manually, etc. are avoided because the liquid sugar can be shipped in tank cars.

The prior art discloses that there are several methods by which various sugars may be made non-crystallizings These differ with the type of sugar under treatment. Sucrose, for example, may be renderedluncrystallizable, or substantially so. by two well known methods: I

1. Sucrose solutions may be acidified and heated whereupon. hydrolysis, or inversion, takes place. By this means more or less of the sucrose may be converted into equal parts of d-glucose and d-fructose. A mixture of sucrose and the two monosaccharides produced by hydrolysis may be achieved. which. is very resistantto' crystallization. This type of hydrolysis may be brought about also by means of the enzyme commonly known as invertase.

2. Dry, crystalline sucrose may be heated to high temperatures. (about 350 F.) according to the method: of GuthyU. S.'Pat. 2,187,122,. with agitation of the melt until rendered non-crystallizing. .Probably this is'a variation of method (1), above, as it is recognized that sucrose does invert to some extent when meltedat high temperatures. It is also possible that some destruction of d-fructose takes place under this treatment.

Dextrose or d-glucose may be rendered noncrystallizing to a substantial degree by alkaline treatment along the lines of the classical method of de Bruyn which results in establishment of an equilibrium mixture of d-glucose (approx. 67%),

d-fructose (approx. 31%) and mannose (approx.

. '2 The treatments outlined above produce noncrystallizing. solutions which are mixtures of sugars and illustrate the well known principle that crystallization of any constituent of a solution isinhibited by the presence of the other soluble constituents if present in substantial quantities.

The main object of the present invention is to produce a, non-crystallizing. solution from a solu-' tion of crude corn sugar or dextrose by a practical method applicable to'commercial production and not giving rise to appreciable coloration orother detrimental side reactions which necessitate'costly refining. This may be accomplished in the following manner: 7

The corn sugar or dextrose solution which may have a reducing sugar. content, calculated as dextrose on dry substance basis, within the limits '70 to 100% is concentrated to not less than 42 B. The solution is acidified to a pH within the limits 0.5 to 4.5 and'the temperature isithen raised to not less than 200 F. and not more than 300 F; Heating is continued within these limits until the reducing sugars calculated, as dextime re diminished by at least 5% depending on the startinglevel. If. the reducing.- sugar content ondry'substance basis is not more than at the start it will be found that a' 5% diminution will be sufficient to inhibit crystallization but if the starting level is higher agreater decreaseis necessary.

Thereaction involved in the process of this invention is unlike the well known acid inversion of ,sucrosezor theider Bruyn type conversion of d-glucose inthei presenceo'f alkali. It also differs from theGuthxprocess for sucrose which is carried out on dry. crystalline material without adjustmentof. pH and which, probably, re-

suits in some-hydrolysis.

-- The product of this invention which also embraces the-essential process. features of heating concentrated dextrose solutions of pronounced acid reaction until the reducing power. (as measured by Fehlings solution) is substantially diminished mayybe characterized by the following features:

1. True-dextrose content is decreased by an amount almost exactly twice that of the diminu tion of the-reducing sugar content.

2. The average molecular weight increased.

, 3. Little coloration is caused if the milder conditionswithinthe scopeof the invention are applied. 1 j

It would appear, therefore, that the process does not; cause hydrolysis even when the. starting 3 carbohydrates have not been converted entirely to dextrose (as in the 70 or 80 corn sugar) and that the reaction is one of condensation or polymerization which produces carbohydrates of larger molecular size from two or more dextrose molecules.

In this manner other carbohydrates are introduced, the presence of which inhibits crystallization of the dextrose from th solution. Some features of the reaction make it resemble the reversion which takes place when acid hydrolysis of starch has proceeded to equilibrium and it is probable that the mechanism is similar. On the other hand it has been found that this reaction, which is carried out at concentrations much higher than those practicable for hydrolysis of 4 a complicated process involving the production of pure dextrose.

A preferred embodiment of this invention, given by way of illustration but not of limitation, is as follows:

Twenty-five thousand pounds of refined 70" com sugar (approx. 82% reducing sugar as dextrose on dry basis) at a concentration of 45 B.

. and pH of 1.5 to 2.5 are run into a regular starch starch, differs from the reversion observed in that reaction in that no limits are imposed to this reversion, condensation, polymerization or whatever it may be. The reaction may be carried on until virtually all of the reducing power of the dextrose solution has been destroyed whereas reversion encountered in starch hydrolysis reaches equilibrium when about 6 to 10% 0f reversion products have been produced.

. The procedure outlined above describes the essential features of the invention but various materials may be added at different points in the process to improve the quality of the product. Where a very close control of the reduction of the D. E. is required a buffering agent may be added to the dextrose solution prior to heating so as to maintain'the pH constant over the range of temperatures employed. As buffering agents phosphates, acetates, phthalates, boric acid compounds, etc. may be employed.

Where a very light coloration is required sulfur dioxide, hydrogen peroxide, chlorine dioxide or other color inhibiting agent may be added to the mass either before or during the acid treating stage or in the neutralizing stage.

Various acids may be employed to reduce the pH of the dextrose solution to a value of 0.5 to 4.5.' Hydrochloric acid is preferred but sulfuric acid, phosphoric acid, the mono-, di-, or trichloraectic acids or any acid capable of reducing the pH of the solution to the desired. amount may be employed. l l

' For neutralizing the converted dextrose solution sodium carbonate is preferred but various other neutralizing agents such as ammonia,'potassium carbonate, or the alkali or alkali earth hydroxides may be employed. l

The non-crystallizing product made by the process of this invention may be likened to a synthetic hydrol or corn sugar molasses in flavor and a number of its chemical properties. It is even more hygroscopic and is, therefore, a good humectant suitable for many purposes. .It does not suffer from the two'outstanding disadvantages of hydrol, however, in that it may be made with low ash content and freedom from heavy coloration.

For example, the product of the present invention is made with an ash content'of less than 2% whereas the ash content of commercial hydrol is usually about 8%. The ash content of theproducts is a measureof a certain type of impurity (for example common salt) in the product and it is apparent that a product with less than 2%ash is adulterated to a smaller degree than a product with 8% ash and that there is also less chance of adding contaminating compounds by employing the product with 2% ash. Inladdition the process for producing hydrol is converter (pressure vessel) into which live steam can be injected by means of an annular distributor at the bottom of the vessel. Steam is introduced until the temperature has risen to 240 F. and held at this level until the reducing sugar content of the solution has dropped to 72%, as determined on samples taken from the converter. The entire mass is then forced (blown under pressure) out of the converter into a tank and is there partially neutralized to a pH of 4.2 to 5.0 with sodium carbonate. Sulfur dioxide and/or activated carbon may be introduced in the converter or neutralizer if a very light coloration is desired. The acid of choice for initial adjustment of pH is hydrochloric.

If desired, the composition of the present invention may be made by mixing a composition which has been treated to a greater degree than the minimum required to produce a noncrystallizing composition and an untreated solution so that the resultant composition contains an excess of 5% of the non-reducing crystallization preventing component. In this way a small amount of equipment may be employed to produce a larger amount of non-crystallizing syrup.

It will be apparent to those skilled in the art that many other variations of the above technique and numerous substitutions of equipment might be made without departing from the scope of the invention.

I claim: r

1. The process of making a liquid and noncrystallizing product from a solution of corn sugar or dextrose having a reducing sugar content calculated as dextrose on the dry basis of 70-10()% which consists of heat treating the solution of 42 to 47 B. at a temperature in the range 200 to 300 F. and an acid reaction of 0.5 to 4.5 pH until the reducing power of the sugars is at least 5% lower than that of the starting solution.

2. The process of making a liquid and noncrystallizing product from a solution of corn sugar or dextrose having a reducing sugar content calculated as dextrose on the dry basis of 70-100% which comprises concentrating the solution of corn sugar or dextrose until it has a specific gravity of at least 42 B., adjusting the pH of the solution to a value of 0.5 to 4.5, heating the solution to a temperature of 200 to 300 F., and continuing the heating until at least 5% of the reducing sugar has been changed to a non reducing crystallization inhibiting sugar component.

3. The process of making a liquid and noncrystallizing solution of dextrose by acidulating a dextrose solution having a D. E. of at least 75 at about 42 Be. to a pH within the range of 0.5 to 2.0 and heating to a temperature within the range of 200 F. to 275 F. until the'D. E. is lowered at least 5 points and neutralizing 'to a pHof4.2to5.0. a,

JAMES E. CLELAND." q

(References on following page) REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES. PATENTS Number Name Date Wagner Dec. 9, 1930 Farber Jan. 14, 1936 Langlois Aug. 8, 1939 Walsh Mar. 5, 1940 10 Dale May 21, 1940 Canlor June 4, 1940 Fetzer Aug. 6, 1940 6 Number Name Date 2,395,907 Peckham Mar. 5, 1946 2,395,938 Peckham Mar. 5, 1946 OTHER REFERENCES Fallons et a1., Ind. and Eng. Chem. 1937 (29), pages 946 to 949.

Kerr, Chem. and Ind. of Starch, New York 1944, pages 272 to 277.

Herman Framm 1941 Chemical Abstract, pages 5860 and 5861.

J. Am. Chem. Soc. Volume 67, pages 51 to 54 (1945).

Claims (1)

1. THE PROCESS OF MAKING A LIQUID AND NONCRYSTALLIZING PRODUCT FROM A SOLUTION OF CORN SUGAR OR DEXTROSE HAVING A REDUCING SUGAR CONTENT CALCULATING AS DEXTROSE ON THE DRY BASIS OF 70-100% WHICH CONSISTS OF HEAT TREATING THE SOLUTION OF 42 TO 47* BE. AT A TEMPERATURE IN THE RANGE 200 TO 300* F. AND AN ACID REACTION OF 0.5 TO 4.5 PH UNTIL THE REDUCING POWER OF THE SUGARS IS AT LEAST 5% LOWER THAN THAT OF THE STARTING SOLUTION.