Process for the recovery of betaine from molasses

Abstract

A process for the recovery of betaine from a molasses comprises a conversion step, in which the molasses is subjected to the action of an enzyme having endo-inulinase activity and/or fructosyltransferase activity, to form a fructan-containing molasses (fructan-molasses); a separation step, in which the fructan-molasses is subjected to a chromatographic separation, thereby obtaining a betaine-containing fraction.

Claims

1. A process for the recovery of betaine from a sugar beet molasses said method comprising the steps of: providing a starting material containing between 45 and 65 wt. % sucrose, between 3 and 8 wt. % betaine, between 6 and 10 wt. % amino acids, as well as fructose, glucose and inorganic salts, wherein the starting material comprises a sugar beet molasses by-product formed in a process for preparation of sucrose, a conversion step, in which the sugar beet molasses starting material is first subjected to the action of a fructan-forming enzyme, having endo-inulinase activity and/or fructosyltransferase activity, whereby at least 80 wt % of the sucrose contained in the sugar beet molasses is converted to form a fructo-oligosaccharide- containing molasses (FOS-molasses); and a separation step, in which the FOS-molasses from the conversion step is subjected to a chromatographic separation, thereby obtaining a betaine-containing fraction having a ratio of betaine to other dry-matter constituents of the FOS-molasses of at least 70:30, wherein: prior to the separation step the FOS-molasses from the conversion step is heated to a temperature of between 80-90 C. and held at such temperature for between 5 and 30 minutes to deactivate the enzyme and reduce any bacteria that may be present in the FOS-molasses, the separation step is accomplished by ion-exchange chromatography in a simulated moving bed chromatography system, a cation exchange resin is used in the ion-exchange chromatographic separation step, and prior to the separation step the molasses or the fructan-molasses is subjected to an ion-exchange step, whereby the concentration of those cations in the molasses or in the fructan-molasses that are different from the cation exchange resin, is reduced by at least 90%.

2. The process according to claim 1, wherein the fruetan-forming enzyme is selected from the group consisting of an enzyme having endo-inulinase activity, an enzyme having fructosyltransferase activity, and a mixture thereof.

3. The process according to claim 1, wherein the cation exchange resin is in sodium form.

4. The process according to claim 1, wherein the concentration of the cations in the molasses or in the fructan-molasses that are different from the cation exchange resin is reduced by at least 95%.

5. The process according to claim 1, wherein the FOS-molasses from the conversion step is heated to a temperature of 85 C. for 5 to 30 minutes prior to the separation step.

6. The process according to claim 1, wherein the FOS-molasses from the conversion step is heated to a temperature of 90 C. for 5 to 30 minutes prior to the separation step.

Description

(1) In the Figures, FIG. 1 shows a graphical representation of the results of the separation step of Example 1.

(2) The process of the invention will be illustrated by means of the following Example, whereby the Example should not be interpreted as limiting the scope of the invention.

EXAMPLE 1

(3) 1000 g of a sugar beet molasses with a solids content of 84% was diluted with water such that the molasses had a solids content of 57.6%; the sucrose content then was 38.5 wt. %. The pH of the molasses was adjusted from 8.1 to 6.2. Any pH adjustments in this Example were done using an aqueous solution of HCl (9%) or an aqueous solution of NaOH (4%). The temperature of the molasses was brought to 56 C. To the molasses, an amount of 591 l of the enzyme Novozyme 960 was added. The molasses was kept at the conditions of pH 6.2 and 56 C. for a period of 24 hours, after which a FOS-molasses had been formed successfully. The amount of FOS was determined to be 51% (wt. % of total carbohydrates).

(4) The FOS-molasses was fed into a batch column for chromatographic separation. The column was 100 cm tall and 5 cm in diameter, and filled for 98 cm with Dowex 99/320 resin in Sodium-form. As is known, this resin is a strong acid cation exchange resin. The eluent, water, was fed into the column at a rate of 10 ml/min; a sample of 70 ml of the FOS-molasses was fed into the column. Between a time frame of 69 minutes and 209 after sample injection, individual fractions were collected per 10 minutes and analysed.

(5) The results are given in Table 1, and in graphical form in FIG. 1.

(6) TABLE-US-00001 TABLE 1 Time Fructose Glucose Sucrose FOS Betaine Rest 69 0.0 0.0 0.0 13.0 0.0 2.0 79 0.0 0.0 1.0 36.0 0.0 5.0 89 0.0 0.0 4.0 49.0 0.0 11.0 99 0.0 2.0 15.0 21.0 0.0 9.0 109 0.0 28.0 5.0 7.0 0.0 4.0 119 0.0 35.0 0.0 0.0 0.0 11.0 129 1.0 4.0 0.0 0.0 0.0 5.0 139 1.0 0.0 0.0 0.0 0.0 1.0 149 0.0 0.0 0.0 0.0 0.0 0.0 159 0.0 0.0 0.0 0.0 0.0 1.0 169 0.0 0.0 0.0 0.0 4.0 0.0 179 0.0 0.0 0.0 0.0 9.0 0.0 189 0.0 0.0 0.0 0.0 8.0 0.0 199 0.0 0.0 0.0 0.0 3.0 0.0 209 0.0 0.0 0.0 0.0 0.0 1.0
Legend to Table 1 Time=Time after sample injection in minutes Numerical values are concentrations in g/kg The fraction Rest contains all dry-matter constituents besides the ones concretely identified in the Table (these are fructose, glucose, sucrose, FOS, and betaine); examples of compounds contained in the fraction Rest are salts

(7) It follows clearly from the results that betaine is obtained in very high purity; the fractions obtained between minutes 169 and 199 contain essentially no sucrose or other compounds, whereas the FOS-containing fractions contain essentially no betaine.