(19)
(11)EP 3 068 854 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
29.07.2020 Bulletin 2020/31

(21)Application number: 14802778.2

(22)Date of filing:  10.11.2014
(51)International Patent Classification (IPC): 
C11B 3/00(2006.01)
C11B 3/12(2006.01)
C11B 3/10(2006.01)
C11B 3/14(2006.01)
(86)International application number:
PCT/US2014/064773
(87)International publication number:
WO 2015/073359 (21.05.2015 Gazette  2015/20)

(54)

REMOVAL OF UNWANTED PROPANOL COMPONENTS

ENTFERNUNG VON UNERWÜNSCHTEN PROPANOLKOMPONENTEN

ÉLIMINATION DES COMPOSANTS DE PROPANOL INDÉSIRABLES


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 14.11.2013 EP 13005366

(43)Date of publication of application:
21.09.2016 Bulletin 2016/38

(73)Proprietor: Cargill, Incorporated
Wayzata, MN 55391 (US)

(72)Inventor:
  • BRUSE, Falk
    D-48317 Drensteinfurt (DE)

(74)Representative: Elseviers, Myriam 
Cargill R&D Centre Europe BVBA Bedrijvenlaan 9
2800 Mechelen
2800 Mechelen (BE)


(56)References cited: : 
EP-A1- 1 746 149
WO-A1-2015/057139
WO-A1-2013/084567
  
  • B Matthäus ET AL: "Mitigation of 3-MCPD esters in refined vegetable oils", Baking + Biscuit International, 1 January 2012 (2012-01-01), pages 12-15, XP055110576, Retrieved from the Internet: URL:http://www.bakingbiscuit.com/id-2012-0 1-sweet-baking/articles/mitigation-of-3-mc pd-esters-in-refined-vegetable-oils.html?f ile=tl_files/f2m-media/pdf/archiv/sweet baking/2012-01/2012-01_12_Mitigation_of_3- MCPD_esters_in_refined_vegetable_oils.pdf [retrieved on 2014-03-28]
  • BERTRAND MATTHÄUS ET AL: "Mitigation of 3-MCPD and glycidyl esters within the production chain of vegetable oils especially palm oil", LIPID TECHNOLOGY, vol. 25, no. 7, 10 July 2013 (2013-07-10), pages 151-155, XP055110706, ISSN: 0956-666X, DOI: 10.1002/lite.201300288
  • FRANK PUDEL ET AL: "On the necessity of edible oil refining and possible sources of 3-MCPD and glycidyl esters", EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, vol. 113, no. 3, 1 March 2011 (2011-03-01) , pages 368-373, XP055027580, ISSN: 1438-7697, DOI: 10.1002/ejlt.201000460
  • OTERHALS A ET AL: "Modeling of a short-path distillation process to remove persistent organic pollutants in fish oil based on process parameters and quantitative structure properties relationships", CHEMOSPHERE, PERGAMON PRESS, OXFORD, GB, vol. 80, no. 2, 1 June 2010 (2010-06-01), pages 83-92, XP027417490, ISSN: 0045-6535 [retrieved on 2010-05-04]
  • Frank Pudel ET AL: "Mitigation of 3-MCPD and G Esters in refined palm oils", 103RD AOCS ANNUAL MEETING & EXPO APRIL 29 - MAY 2, 2012, 29 April 2012 (2012-04-29), pages 21-22, XP055338855, Retrieved from the Internet: URL:http://aocs.files.cms-plus.com/Technic alPDF/Mitigation of 3-MCPD and G Esters in Refined Palm Oils.pdf [retrieved on 2017-01-25]
  • Anonymous: "3-MCPD Esters in Food Products", ILSI Europe, 1 February 2009 (2009-02-01), pages 1-36, XP055403507, Retrieved from the Internet: URL:http://ilsi.eu/publication/mcpd-and-gl ycidyl-esters-in-food-products/ [retrieved on 2017-09-04]
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

Field of the Invention



[0001] The present invention relates to the removal of unwanted propanol components in deodorized triglycerides.

Background of the Invention



[0002] Crude oils, as extracted from their original source, are not suitable for human consumption due the presence of high levels of contaminants - such as free fatty acids, phosphatides, soaps and pigments - which may be toxic or may cause an undesirable colour, odour or taste. Crude oils are therefore refined before use. The refining process typically consists of three major steps: degumming, bleaching and deodorizing. An oil obtained after completion of the refining process (called a "refined oil") is normally considered suitable for human consumption and may therefore be used in the production of any number of foods and beverages. It has now been found that the crude oil refining process itself contributes to the introduction, of various levels of 3-monochloropropane-1,2-diol fatty acid esters (3-MCPD esters) and glycidyl esters. 3-MCPD ester and glycidyl ester amounts are depending on oil type and refining process. Most vegetable oils show 3-MCPD ester contents between 200-800 ppb and Glycidyl ester content below 500 ppb, but for palm oil or specific process conditions values even above 5000 ppb might be found.
Free 3-monochloropropane-1,2-diol (3-MCPD) has been identified as a contaminant for a long time in various foods. Recent studies have identified 3-MCPD fatty acid esters in refined edible fats and in fat-containing foods. 3-MCPD esters are formed at high temperatures, in particular during deodorization. Also 2,3-epoxy-1-propanol (glycidol) is formed in the deodorization step. Both glycidyl esters and 3-MCPD esters are associated with a possible carcinogenic effect.

[0003] EP 2 449 070 describes a process for removing unwanted propanol components from unused triglyceride oil including contacting the contaminated oil with an adsorbent.

[0004] A further suggestion for reducing 3-MCPD ester content is made in WO2010/036450 (Süd-Chemie). It is based on a modified refining process which uses very intensive bleaching (with high amounts of bleaching clays).

[0005] WO2012/107230 describes an alternative process for the reduction of 3-MCPD and/or glycidyl ester content and wherein the process comprises subjecting an oil to the following steps, in order: a) a bleaching step, b) a deodorization step, c) a final bleaching step, and d) a final deodorization step wherein the final deodorization step d) is carried out at a temperature at least 40°C lower than deodorization step b).

[0006] Matthäus describes in Baking + Biscuit International, 1/1/2012 pages 12-15 the mitigation of 3-MCPD esters in refined vegetable oils. It describes a first step at high temperature (250-270°C) combined with a second step at lower temperature (200°C) or vise versa, to reduce 3-MCPD esters.

[0007] Matthäus describes in Lipid Technology vol 25, 2013, pages 151-155 the mitigation of 3-MCPD and glycidyl esters within the production chain of vegetable oils especially palm oil. It describes the use of short path evaporation as replacement for deodorization.

[0008] WO 2015/057139 describes the mitigation of 2-MCPD, 3-MCPD esters and glycidyl esters and describes a process with a short path evaporation applied at temperatures from 230°C or more.

[0009] WO 2013/084567 describes palm based oil and method for producing same, by applying a short path evaporation on RBD oil.

[0010] EP 1 746 149 describes a process with short path evaporation to produce edible oil with high diglyceride content.

[0011] Frank Pudel describes in 103rd AOCS Annual Meeting 2012 pages 21-22, the mitigation of 3-MCPD and glycidyl esters in refined palm oils and provides a list of measures of mitigation.

[0012] ILSI Europe 2009, pages 1-36 describes 3-MCPD esters in Food products and the need to optimize the refining process.

[0013] It would be desirable to have a simple, mild but effective process for the removal of these unwanted propanol fatty acid esters.
The current invention provides such a process.

Summary of the Invention



[0014] The current invention relates to the use of short-path evaporation for reducing from refined, bleached, deodorized palm oils the content of propanol components selected from epoxypropanol fatty acid esters (= glycidyl esters), wherein the short path evaporation is performed at a pressure below 1 mbar, preferably below 0.05 mbar, more preferably below 0.01 mbar, most preferably below 0.001 mbar and at a temperature of from 150 to 210°C.

Detailed Description



[0015] The current invention relates to the use of short-path evaporation for reducing from refined, bleached, deodorized palm oils the content of propanol components selected from epoxypropanol fatty acid esters, wherein the short path evaporation is performed at a pressure below 1 mbar, preferably below 0.05 mbar, most preferably below 0.01 mbar, most preferably below 0.001 mbar and at a temperature of from 150 to 210°C.

[0016] The current invention relates to the use wherein the content of propanol components selected from epoxypropanol fatty acid esters is reduced to a content below 500 ppb, preferably below 300 ppb, even more preferably below 150 ppb.

[0017] In a preferred embodiment, these propanol components are completely removed (i.e. below limit of quantification).

Short path evaporation



[0018] Short path evaporation is a distillation technique that involves the distillate travelling a short distance, often only a few centimeters, and is normally done at reduced pressure. This technique is often used for compounds which are unstable at high temperatures or to purify small amounts of compound. The advantage is that the heating temperature can be considerably lower (at reduced pressure) than the boiling point of the liquid at standard pressure, and the distillate only has to travel a short distance before condensing. A short path ensures that almost no compound is lost on the sides of the apparatus.
The current invention relates to the use according to claim 1.

[0019] Furthermore, the short path evaporation is performed at a pressure below 1 mbar, preferably below 0.05 mbar, more preferably below 0.01 mbar, most preferably below 0.001 mbar.

[0020] The use of the short path evaporation allows reducing the content and/or complete removal of Glycidyl esters components..

[0021] Unless specified otherwise, the content of 3-MCPD esters and glycidyl esters either alone or in combination will be determined using Method DGF Standard Methods Section C (Fats) C-VI 18(10) or C-VI 17(10).

[0022] The triglyceride oil that is entering the short path evaporator is derived from palm oil.

[0023] Refining of oils involves degumming and/or neutralization. Degumming is the first stage in the refining process. It is used to separate the gums, phospholipids, proteins etc, that are insoluble in oil when hydrated.

Bleaching



[0024] Bleaching is a process whereby impurities are removed to improve the color of the oil. It is typically performed prior to deodorization. The nature of the bleaching step will depend, at least in part, on the nature and quality of the oil being bleached. Generally, a crude or partially refined oil will be mixed with a bleaching agent which combines with oxidation products (e.g. peroxides), trace phosphatides, trace soaps, pigments and other compounds to enable their removal. The nature of the bleaching agent can be selected to match the nature of the crude or partially refined oil to yield a desirable bleached oil. Bleaching agents generally include natural or "activated" bleaching clays, also referred to as "bleaching earths", activated carbon and various silicates. A skilled person will be able to select a suitable bleaching agent from those that are commercially available based on the oil being refined and the desired end use of that oil.

Deodorization



[0025] Deodorization is a process whereby free fatty acids (FFAs) and other volatile impurities are removed by treating (or "stripping") a crude or partially refined oil with steam, nitrogen or other inert gasses. The deodorization process and its many variations and manipulations are well known in the art and the deodorization step(s) of the present invention may be based on a single variation or on multiple variations thereof.
Deodorization is typically carried out at elevated temperatures and reduced pressure to better volatilize the FFAs and other impurities. The precise temperature and pressure may vary depending on the nature and quality of the oil being processed. The pressure, for instance, will preferably be no greater than 10 mm Hg but certain aspects of the current invention may benefit from a pressure below or equal to 5 mm Hg, e.g. 1-4 mm Hg. The temperature in the deodorizer may be varied as desired to optimize the yield and quality of the deodorized oil. At higher temperatures, reactions which may degrade the quality of the oil will proceed more quickly. For example, at higher temperatures, cis-fatty acids may be converted into their less desirable trans form. Operating the deodorizer at lower temperatures may minimize the cis- to-trans conversion, but will generally take longer or require more stripping medium or lower pressure to remove the requisite percentage of volatile impurities. As such, deodorization is typically performed at a temperature in a range of 180 to 280°C, with temperatures of about 220-270°C being useful for many oils (note: the temperatures reflect the temperatures reached by the oils in the deodorizer rather than, for example, that of the steam used during the process). While deodorization is used to remove free fatty acids (FFA) and other volatile impurities, it is also known that during the deodorization step, more in particular at high temperature, propanol components such as chloropropanol fatty acid esters, and epoxy propanol fatty acid esters may be formed.

[0026] The invention will hereunder be illustrated in following examples.

Examples


Analytical Methods


3-MCPD determination



[0027] Analysis of 3-MCPDE and GE either alone or in combination was performed according to DGF-C-VI 17(10) or DGF-C-VI 18(10.

Oil composition



[0028] GPC was used to analyze free fatty acids (=FFA), mono-acyl glycerides (= MAG), di-acyl-glycerides (=DAG), and triglycerides (=TAG).

Example 1 -



[0029] Starting material Refined, bleached and deodorized palm oil (= RBD palm oil) from Cargill.

[0030] Short Path Evaporation Unit KDL-5 from UIC was used for the short path evaporation.

[0031] The following conditions were applied:
Feed-temperature: 70°C
Condenser Temp.: 90°C
Distillate Temp.: 70°C
Wiper speed: 366 rpm
Pressure below 10-3 mbar (is within detection limit).
   
Stabilization time perindividual setting: 10 min for Temp. change, 5 min for flow change


[0032] Feed rate and evaporator temperature were adjusted as given in below table.

[0033] The results are shown in Table 1
Table 1: Residue composition of samples from SPE of RBD Palm Oil
Evaporato r Temp °CFlow settin gTAGDAGMAGFFA3-MCPD (ppm)GE (ppm)
RBD Start 89,93 8,91 0,17 0,60 3,5 6,28
120 800 90,10 8,84 0,57 0,33 3,12 6,73
120 200 90,06 8,82 0,68 0,31 3,23 5,35
150 800 90,14 8,86 0,52 0,35 3,46 5,8
150 200 90,06 8,84 0,62 0,48 3,2 2,64
180 800 87,89 8,97 0,11 0,41 3,38 1,03
180 800 90,26 8,81 0,51 0,42 2,96 1,65
180 200 88,09 9,02 0,00 0,31 3,45 0,48
180 200 90,36 8,77 0,41 0,45 2,59 1,65
210 800 88,10 8,98 0,00 0,31 3,1 0,00
210 800 90,59 8,63 0,38 0,40 2,82 0,36
210 200 89,20 8,06 0,00 0,18 2,5 0,23
210 200 91,78 7,51 0,30 0,41 2,15 0,68
240 800 88,16 8,93 0,00 0,30 3,2 0,85
240 800 91,49 7,80 0,30 0,41 2,19 1,13
240 200 96,54 2,88 0,21 0,37 0,55 0,23
240 100 95,27 2,01 0,00 0,23 0,47 0,16
240 40 97,14 0,00 0,00 0,26 0,31 0,09

Example 2 (not part of the invention)



[0034] Starting Material is refined, bleached and deodorized coconut oil (= RBD CNO) from Cargill.

[0035] The following conditions were applied:
Feed-temperature: 70°C
Condenser Temp.: 90°C
Distillate Temp.: 70°C
Wiper speed: 366 rpm
Pressure below 10-3 mbar
   
Stabilization time per individual setting: 10 min for Temp. change, 5 min for flow change


[0036] Feed rate and evaporator temperature were adjusted as given in below table.

[0037] The results are shown in Table 2
Table 2: Residue composition of samples from SPE of RBD CNO
Tem pFlo w3-MCPD (ppm)GE (ppm)
CNO start 0,85 0,35
120 200 0,87 1,70
150 200 0,67 0,37
180 200 0,39 0,01
190 200 0,14 0,09
200 200 0,19 -0,02
210 200 0,12 -0,04
240 200 0,02 0,05



Claims

1. Use of short-path evaporation for reducing from refined, bleached, deodorized palm oil the content of propanol components selected from epoxypropanol fatty acid esters, wherein the short path evaporation is performed at a pressure below 1 mbar, preferably below 0.05 mbar, more preferably below 0.01 mbar, most preferably below 0.001 mbar, and at a temperature of from 150°C to 210°C.
 
2. The use according to claim 1 wherein the content of propanol components selected from epoxypropanol fatty acid esters, is reduced to a content below 500 ppb, preferably below 300 ppb, even more preferably below 150 ppb.
 


Ansprüche

1. Verwendung von Kurzwegverdampfung zum Reduzieren des Anteils von aus Epoxypropanolfettsäureestern ausgewählten Propanolbestandteilen an raffiniertem, gebleichtem, desodoriertem Palmöl, wobei die Kurzwegverdampfung bei einem Druck unter 1 mbar, vorzugsweise unter 0,05 mbar, noch bevorzugter unter 0,01 mbar, am bevorzugtesten unter 0,001 mbar, und bei einer Temperatur von 150 °C bis 210 °C durchgeführt wird.
 
2. Verwendung nach Anspruch 1, wobei der Anteil von aus Epoxypropanolfettsäureestern ausgewählten Propanolbestandteilen auf einen Anteil unter 500 ppb, vorzugsweise unter 300 ppb, noch bevorzugter unter 150 ppb reduziert wird.
 


Revendications

1. Utilisation d'une évaporation à chemin court pour réduire à partir d'une huile de palme raffinée, blanchie, désodorisée la teneur en composants propanols sélectionnés parmi des esters d'acide gras d'époxypropanol, dans laquelle l'évaporation à chemin court est effectuée à une pression inférieure à 1 mbar, de préférence inférieure à 0,05 mbar, plus préférentiellement inférieure à 0,01 mbar, le plus préférentiellement inférieure à 0,001 mbar, et à une température de 150 °C à 210 °C.
 
2. Utilisation selon la revendication 1, dans laquelle la teneur en composants propanols sélectionnés parmi des esters d'acide gras d'époxypropanol est réduite à une teneur inférieure à 500 ppb, de préférence inférieure à 300 ppb, encore plus préférentiellement inférieure à 150 ppb.
 






Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description




Non-patent literature cited in the description