Claims
- 1. A process for refining fatty substances that contain fatty acids which comprises:preparing a reaction medium by mixing the fatty substances with an aqueous medium containing one of an alcohol or a polyol; removing free fatty acids from the fatty substances in a neutralization step by gradually adding a base to the reaction medium to increase and maintain the pH in the range of about 9 to 11 so as to partition the free fatty acids between a lipid phase and an aqueous phase, containing the alcohol or polyol, which phase is nonmiscible with the lipid phase, and to form soaps which are solubilized in the aqueous phase, thus producing a shift in equilibrium and a gradual deacidification of the lipid phase until the pH is stabilized in the range of 9 to 11; and separating the aqueous phase from the lipid phase to obtain the refined fatty substance.
- 2. The process of claim 1, wherein the neutralization step is carried out in the presence of alcohol, in a homogeneous medium with slow stirring, at a temperature greater than the melting point of the fatty substance and less than the azeotropic boiling point of the aqueous medium.
- 3. The process of claim 2, wherein, the alcohol is a C1-C3 alcohol.
- 4. The process of claim 2, wherein the alcohol is ethanol or 2-propanol.
- 5. The process of claim 1, wherein the neutralization step is carried out in a reactor equipped with a pH electrode, a stirrer and a pH-stat equipped with a burette for delivering aqueous alkaline solution, and the pH-state is connected to the pH electrode so as to provide additional alkaline solution as required to maintain the pH in the range of 9 to 11.
- 6. The process of claim 5, wherein the reactor is operated to provide stirring conditions such that the lipid phase and the aqueous phase remain separated during the neutralization step to avoid the formation of stable emulsions due to the presence of soaps, and the pH electrode is maintained in contact with the aqueous phase alone.
- 7. The process of claim 1, wherein the fat:alcohol volume ratio is 1:0.5 to 1:2.5 and the neutralization step is conducted for 6 to 20 h.
- 8. The process of claim 1, wherein the neutralization step is carried out in a heterogeneous medium, with vigorous stirring, in the presence of the alcohol or polyol at a temperature of 40 to 80° C. without using a pH-stat.
- 9. The process of claim 8, wherein the quantity of alkali just required for the neutralization is calculated, without excess of alkali, relative to the quantity of free fatty acids present.
- 10. The process of claim 8, wherein the quantity of free fatty acids present is determined by colorimetric titration.
- 11. The process of claim 8, wherein the neutralization is carried out in about 60 minutes.
- 12. The process of claim 1, wherein the polyol is glycerol, propylene glycol, ethylene glycol or a polyalkylene glycol, in particular polyethylene glycol, polypropylene glycol, anhydrous or diluted with water.
- 13. The process of claim 1, wherein the polyol:fat weight ratio is about 0.5 :10 to 1:1.
- 14. The process of claim 1, wherein the fatty substance is degummed and dewaxed coffee oil, millet oil or rice bran oil.
- 15. The process of claim 1, wherein the fatty substance is a synthetic mixture of an interesterified fat.
- 16. The process of claim 1, wherein the alkali is an aqueous solution of KOH or NaOH at concentrations of 1 to 40% by weight.
Priority Claims (1)
Number |
Date |
Country |
Kind |
98202698 |
Aug 1998 |
EP |
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of the U.S. national stage designation of International Application PCT/EP99/05333 filed Jul. 20, 1999, the content of which is expressly incorporated herein by reference thereto.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
2844613 |
Cousins et al. |
Jul 1958 |
A |
3008972 |
Mitani |
Nov 1961 |
A |
Foreign Referenced Citations (5)
Number |
Date |
Country |
596871 |
Jan 1948 |
GB |
1520523 |
Aug 1978 |
GB |
50103506 |
Aug 1975 |
JP |
4370195 |
Dec 1992 |
JP |
5306400 |
Nov 1993 |
JP |
Non-Patent Literature Citations (1)
Entry |
A.C. Bhattacharyya et al., “Edible Quality Rice Bran Oil from High FFA Rice Bran Oil by Miscella Refining”, Journal of the American Oil Chemists' Society, vol. 63, No. 9, pp. 1189-1191 (1986). |
Continuations (1)
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Number |
Date |
Country |
Parent |
PCT/EP94/05333 |
Jul 1999 |
US |
Child |
09/780899 |
|
US |