Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11B—PRODUCING, e.g. BY PRESSING RAW MATERIALS OR BY EXTRACTION FROM WASTE MATERIALS, REFINING OR PRESERVING FATS, FATTY SUBSTANCES, e.g. LANOLIN, FATTY OILS OR WAXES; ESSENTIAL OILS; PERFUMES
  • C11B3/00—Refining fats or fatty oils
  • C11B3/001—Refining fats or fatty oils by a combination of two or more of the means hereafter

Definitions

• a refined fish oil concentrate and the production process for same A refined fish oil concentrate and the production process for same.
• the present invention concerns a refined fish oil concentrate as well as the production process for same.
• cholesterol and useful biproducts such as urea adducts of fatty acid compounds are produced, in addition to higher unsaturated fatty acids.
• waste products from the fish refining indu ⁇ stry contain usable products, among others fatty acids, chol ⁇ esterol, proteins and enzymes. These are either fat-soluble or water-soluble. Such waste products are normally referred to as fish entrails.
• the water-soluble portion containing proteins and enzymes may be separated from the fat-soluble portion.
• the present invention concerns only the fat-soluble portion of the waste products, but it can also be used for other refined fish oils such as occur for instance in the fish product industry. In the following this will be called fish oil product.
• fatty acids the following may be specified as suitable for the medicinal purpose referred to: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Both fatty acids are « ⁇ > 3-fatty acids of the C-20 and C-22 acids. Their nomenclature according to the IUPAC system is:
• EDA eicosapentaensoic acid
• DHA docosahexaenoic acid
• 20 and 22 indicate the number of C-atoms in the mole ⁇ cule of fatty acid, 5 and 6 the number of unsaturated bondings, and ⁇ 3 that the last unsaturated bonding is posi ⁇ tioned in a distance of 3 carbon atoms from the u)-position.
• the fat soluble portion of cod entrails usually contains 10 - 25% of the essential fatty acid compounds EPA and DHA, as well as 2 - 4% cholesterol.
• the remainder is mainly fatty acid compounds with lower unsaturation, such as pure fatty acids or their glycerides.
• the purpose of the invention is to separate the essential fatty acid compounds from cholesterol and the remaining fatty acid compounds.
• Another purpose of the invention is to produce from a non-uniform raw material containing marine fatty acids and/or esters of these fatty acids, as well as cholesterol as main components after trans-esterification with a lower alcohol, and under alkaline conditions produce a concentrate con ⁇ taining the essential u3-fatty acid compounds, EPA and DHA, as well as isolate the cholesterol and the urea adduct of the saturated and lower unsaturated fatty acid compounds, which then appear in their own product fractions.
• esters for instance as methyl or ethyl esters.
• trans-esterification and esterification for instance with methanol for production of fatty acid methyl esters.
• This basic material is well suited for further separation of essential fatty acid compounds and cholesterol from the remaining less important fatty acid compounds.
• Another patent, SU 950.393 describes a method for production of cholesterol from for instance fish waste products by hydrolysing the fatty acid compounds and converting, them to soaps. These are then subjected to an extraction of trichlor- ethylene at room temperature, whereby the cholesterol is com ⁇ bined with the trichlorethylene and this compound is then subject to further separation.
• GB 1.240.513 also concerns a separation technique by means of urea where the raw material consists of pure methyl and ethyl esters of the C,g-C,gfatty acids. Urea precipitation occurs in a neutral environment with a surplus of the rele ⁇ vant alcohol. The purpose is to be able to obtain a stronger concentration of the V -linolenic acid.
• the above-mentioned fatty acid esters do not contain any higher fatty acids other than C-18 in the form of stearic acid, oleic acid, linoleic acid and linolenic acid, which after the urea precipitation and. separation of the urea adduct from the rest of the material has obtained a higher content of X -linolenic acid by means chromotography.
• the higher unsaturated fatty acid compounds 20:5 u)3 and 22:6 -J3 may be concentrated according to a method described in J 59-071396 where the fatty acid compounds men ⁇ tioned are extracted by means of polar solvents, such as ace ⁇ tone, methyl ethyl ketone, methanol, ethanol, and similar solvents, whereby a soluble and an insoluble extract are formed. Thereafter the extract is further processed to obtain essential fatty acid compounds.
• polar solvents such as ace ⁇ tone, methyl ethyl ketone, methanol, ethanol, and similar solvents
• Another special feature is that the precipitation of urea takes place in an alkaline environment, and in such a way that the alkaline environment is created through applying the base only in catalytic quantities such as a catalytic agent for the trans-esterification of glycerides to methyl esters and not as a means of saponification of the fatty acids.
• a third special feature is that the trans-esterification takes place at room temperature.
• a result of trans-esterification at low temperature and in an environment with low alkalinity is that isomerization of the double compounds is avoided, which results in a more uniform product with no toxic effect.
• transcon- figurations are avoided.
• the remaining solution is thereafter extracted by means of non-polar solvents, among others hex ⁇ ane, whereby the t ⁇ 3-fatty acids as well as cholesterol will be found in the hexane phase.
• the basic material is fat and/or fatty acids from fish and especially fat and/or fatty acids obtained from the fish processing industry in connection with ensilage and or auto- catalysis processes, but the process may also be used for other forms of marine fat.
• This fatty raw material is called a fish oil product in the claims.
• Such fat/fatty acids have a high content of saturated, unsaturated and polyunsaturated fatty acids with a chain length C 18, C 20 and C 22 as well as a certain amount of cholesterol, vitamins and other fat soluble products which are undefinable, usually characterized as unsaponifiable, as well as fatty acid compounds with shorter chain lengths.
• B alcohol with a low boiling point
• B for instance methanol or ethanol, prefer ⁇ ably methanol
• C auxiliary compounds
• Potassium hydroxide may be used as a catalytic agent and in order to prevent oxidization, especially when heavy metals are present, such as chromium, iron, cobalt, nickel and copper, small amounts of the sodium salt of ethyl- enediaminetetra-acetic acid (EDTA-Na 3 ) may be added.
• EDTA-Na 3 sodium salt of ethyl- enediaminetetra-acetic acid
• the esterification and trans-esterification take place under moderate conditions and stirring at about 20° C for some hours.
• the formation of alkyl esters is nearly complete when the ester product has changed its appearance from opalescent to clear.
• the clear solution (Dl) therefore contains alkyl esters of the fatty acids, glycerol, alkanol, as well as some water from the esterification of the free fatty acids.
• urea (E) and alkanol (B) are added and stirred in until everything is completely dissolved.
• the amount of urea depends on the composition of the fatty acids so that if the raw material (A) contains 6-8% EPA by weight, urea is added in the ratio 3 parts urea by weight to 1 part alkyl ester. In order to ensure that the components are completely soluble, 9 parts alkanol by weight is added.
• the slightly alkaline filter mass (G) is saturated with hex ⁇ ane and is extracted by means of this solvent through a known technique as for instance by a continuing fluid-to-fluid counter current process, whereafter a further quantity of adduct of urea fatty ester may be crystallized.
• two fluids are formed, consisting of hexane (I) and a residue (K). Box 4.
• the hexane extract (I) which contains the alkyl-fatty esters of the polyunsaturated fatty acids 18:4 ⁇ )3, 20:5 tt>3-and 22:64)3 as well as cholesterol as the most important com ⁇ ponents, is washed in a diluted hydrochloric acid ( ) in order to neutralize possible potassium soaps of the essential polyunsaturated fatty acids in the hexane extract.
• the washing water is decanted.
• Hexane (H) is thereafter removed by evaporation of the extract (I) so that a concentrate is produced which is free from solvents (N) and which contains the compounds that are essential for the invention, the fatty acid compounds EPA and DHA as well as cholesterol.
• the dehydrated extract normally contains 20-30 % EPA, 35-45% DHA, 10-20% other polyunsaturated fatty acids, as well as 5-15% cholesterol and undefined compounds, all by weight, but the composition referred to will depend on the type of fish used, the time of year the fish is caught, and the type and condition of the raw material.
• the concentrate of alkyl fatty acid ester (N) is thereafter cooled to approx. minus 25° C, whereafter cholesterol (0) is crystallized. This is centrifuged/filtered. Further impurities which are present in the concentrate (N) may be removed by cooling the mixture to a temperature of lower than minus 25 C, whereafter certain undefined com ⁇ pounds are precipitated and filtered by means of a known method.
• the remaining «J3-concentrate (P) thus contains 20-35% EPA, 35-50% DHA and 15-25% of other polyunsaturated ⁇ 3-fatty acid compounds (all by weight) as well as unsatur ⁇ ated fatty acid compounds which are not essential for the invention.
• Product (P) which contains the alkyl esters of the corre ⁇ sponding ⁇ 3-fatty acids may be utilized as it is or the con ⁇ centration of EPA and DHA may be increased.
• the product contains only small amounts of other fatty acids with the same chain length as EPA and DHA, it is well suited for separation of the essential fatty acids, EPA and DHA by means of supercritical fluid extraction.
• Another method for increasing the concentration is by means of preparative liquid chromatography by which method a mors than 90% purity of the essential fatty acids is obtained.
• the hexane fractions (R) contain free fatty acids as well as some of their alkyl esters and fairly high percentages of EPA and DHA, but also a fairly substantial portion of C 18-, C 20- and C 22-fatty acids with lower unsaturation.
• This acid solution contains water, alcohol, alkanol, glycerol, urea and other products which may be retrieved by a separate process which is not described here.
• the fatty acid components of the hexane fraction are increased by evaporating hexane (H) in a separate piece of equipment.
• the remaining solution is esterified using lower alkanols, for instance methanol or ethanol by means of an appropriate catalytic agent (V) which for instance may be dehydrated hydrochloric acid, acetic acid chloride or boron-trichloride.
• V catalytic agent
• the resultant alkyl ester (D2) from the fatty acid components (T) from box 7 may be processed in various ways, for instance returned to box 2 for urea precipitation of the less unsatur ⁇ ated fatty acids.
• the whole mixture was subjected to stirring for 15 hours at 20°C in order to bring about a trans-esterification of the glycerides to methyl esters and esterification of the free fatty acids to methyl esters.
• the urea adduct was separated from the solution by decanting and filtering according to an ordinary, known technique. Result: 100.1 kg urea adduct (F). Thereafter the solution was cooled to 0 - 4° C, whereby an additional 5.1 kg urea adduct (F) could be filtrated from the solution.
• This filtrate (G) contained u/3-polyunsaturated fatty acid methyl esters, cholesterol and a residue of unwanted fatty acid fractions with lower unsaturated C 18, C 20 and C 22 fatty acid methyl esters.
• To this filtrate we added hexane for saturation, whereby a further amount of urea adduct (22 kg) could be separated.
• This hexane-saturated solution was extracted in a counter-current with hexane so that the hexane extract (I) finally made up approx. 300 1. The remaining unextracted solution is called (K). The hexane extract was thereafter evaporated.
• the yield of 3-fatty acid methyl ester concentrate 10.2 kilos.
• the concentrate (N) which contained 23% EPA , 41% DHA and 8% cholesterol, all by weight, was thereafter cooled to minus 25°C, whereby pure cholesterol (0) crystallized and was removed by means of centrifuging during which time the resi ⁇ due in the centrifuge was washed with hexane with a lower temperature in order to remove the fatty acid methyl esters from the cholesterol crystals. Yield: 760 g pure cholesterol.
• the concentrated filtrate (P) contained 25% EPA-methylester, 43% DHA-methylester by weight based on the fatty acid portion and traces of cholesterol.
• Another advantage with the invention is that it is possible to produce a urea adduct based on the same procedure where a trans-esterification has been done from glycerides to alkanol esters without following the cumbersome procedure by first producing the fatty acids, esterify these with alkanol and then separate them by means of the fractionated urea preci ⁇ pitation.

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• Life Sciences & Earth Sciences (AREA)
• Microbiology (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Fats And Perfumes (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Medicines Containing Material From Animals Or Micro-Organisms (AREA)

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• 1985
  • 1985-12-19 NO NO855147A patent/NO157302C/no not_active IP Right Cessation
• 1986
  • 1986-11-21 DE DE8686906964T patent/DE3668467D1/de not_active Expired - Lifetime
  • 1986-11-21 IS IS3159A patent/IS1425B6/is unknown
  • 1986-11-21 IE IE306486A patent/IE59171B1/en not_active IP Right Cessation
  • 1986-11-21 EP EP86906964A patent/EP0255824B1/de not_active Expired - Lifetime
  • 1986-11-21 WO PCT/NO1986/000077 patent/WO1987003899A1/en active IP Right Grant
  • 1986-11-21 AU AU66211/86A patent/AU6621186A/en not_active Withdrawn
  • 1986-11-25 ZA ZA868927A patent/ZA868927B/xx unknown
  • 1986-11-27 CA CA000523914A patent/CA1303416C/en not_active Expired - Lifetime
  • 1986-12-03 NZ NZ218500A patent/NZ218500A/xx unknown
  • 1986-12-08 MX MX004578A patent/MX168698B/es unknown
  • 1986-12-17 DD DD86297792A patent/DD261805A1/de not_active IP Right Cessation
  • 1986-12-19 MA MA21072A patent/MA20840A1/fr unknown
  • 1986-12-19 AR AR86306258A patent/AR242111A1/es active
  • 1986-12-19 PT PT83991A patent/PT83991B/pt not_active IP Right Cessation

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