DE2127596A1 - Process for the production of vegetable fats and oils. - Google Patents

Description

Process for the production of vegetable fats and oils

Of the methods for the production of vegetable oils and fats that have been known and used industrially for a long time, the most important to be listed as follows:

1. Extraction by mechanical pressing

2. Obtaining by extraction

3. Extraction by boiling out, steaming out, melting out

Of these, the first two are by far the most frequently used processes. While it is not possible to retain the entire fat content of the fruit during pressing, the fats can be extracted from the material to less than 1% during extraction.

In some cases, extensive pretreatments are required for all procedures, which relate, among other things, to the crushing and shaping of the plant material. To pose a major problem at the extract! The solvent residues in the fat proceed as well in the extraction residue, some of which is used for feed purposes.

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0106γΐ-Α _Λ

distant, and so this problem is dealt with with considerable technical and economic effort; the discussion about it continues. For these reasons in particular, extraction processes for fats are completely forbidden in some countries, so here
only pressing processes are permitted, with the associated poorer yields.

The present invention provides a new process for the production of vegetable fats and oils, especially seed fats. It is based on the observation that in relation to
Pressure and temperature supercritical, health, taste and chemically harmless gases a solvent for
Vegetable fats are.

The method according to the invention for obtaining vegetable fats and oils, in particular vegetable fats, by extraction with a solvent, is characterized in that the fat is extracted from the seeds by extraction with supercritical gases which are harmless to health and from the resulting
Solution separates the fat by changing the pressure and / or temperature.

The invention is hereinafter referred to as the extractant
particularly preferred COp described, but can with
The same success is also achieved with the gases SFg, CHF ^ ₅ , CF ^ Cl, CFp = CHp, CHFpCl, CJg, which are also harmless in terms of taste, health and chemistry, which are used with COp isostere NpO and ethane or ethylene alone or in a mixture,
after they have been subjected to a pre-purification such as distillation. The preferred working conditions specified in the 4 cases explained below are to be transferred accordingly for the gases listed with regard to their critical data, which are known from the literature.

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It should be ^nerkt%, that extraction with CO ^ in liquid, that is subcritical, - possible condition, which, incidentally, also applies to the other gases that are listed above. However, the solving power changes abruptly during the transition to the supercritical state and is considerably greater here. With the proposed method, it is possible to completely extract the fats in their natural composition from the plant material without chemical changes, including the residue. The method works in a preferred embodiment, which is explained by the accompanying drawing, as follows:

The container Λ is used with the ground or roughly chopped Material loaded. A special shape is not required, and the removal of shells or sleeves is not necessary necessary if they do not contain components that could be extracted and that are undesirable in the fat. After removal From Lüftsauersto'ff by flushing the entire system with COp is introduced into the container A supercritical COp and charges here with the vegetable fat in the sense of a "supercritical solution".

The container is equipped with fine-pored metal filter discs (filter eye wave 3-5 li) closed, so that a mechanical dragging along of plant parts is not possible. The gas flow is then transferred via the heat exchanger W 3 to the container B and there segregated. This is preferably done by lowering the pressure to values <P,.,, Gas. The temperature can also be set to values <t. .., gas lowered, at the same level as in the extraction vessel Leave A or increase it.

(Basically, an increase in temperature, as well as a decrease in pressure, under P _crit also lead to system mixing. Both effects can be combined, but one has to be guided by the thermal load capacity of the extract. This results in various process variants, which are listed below ).

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If the temperature of the "loaded" gas flow on entry into the container B is _{lowered below ^ kri} ^ during the demixing, liquefaction of the CO ₂ occurs. It has been shown that in this case, in addition to the separation of the extract, ie the fat, the water from the vegetable material is also separated B does not fall below t _v ., But remains above it. The fat components also separate, but only very small amounts of water, so that with this method of operation a fat that is practically anhydrous is obtained. (The removal of the fats from container B after the end of the extraction is particularly easy by bringing the temperature to values above the clear melting point, lowering the pressure in container B to a few atmospheres and drawing off the fat or oil in liquid form Separation of the dissolved CO _2. This also acts as

inert gas). - The extract from the f ^ eije__Gass ^ tr_om is extracted from the container

ter B, conveyed by means of a liquid gas pump or compressor and 'compressed and re-enters the extraction tank A as a pure solvent, and so on. Depending on the solvent selected, the heat exchangers W 1 and W 2 have different functions. When conveying with a liquid gas pump, the CO _{2 must be} liquefied in the heat exchanger V / 2 "and the medium in the heat exchanger W 1 must be heated to supercritical conditions. When using a compressor, the medium in the heat exchanger W-2 may have to be brought to supercritical temperatures, while the heat of compression is to be dissipated in W 1. In practice, the heat exchangers are interconnected, so that particularly economical operating options arise with regard to the energy requirement.

As mentioned, different combinations of the parameters pressure and temperature during demixing allow different process variants. (Here P ₁ and 'tj. Relate to pressures and temperatures in extraction _{tank A, P 2} and t _? To separation tank B):

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Of = HGfNAL INSPECTED

010671-A

1st case: Conditions: P ₀ <CP

_krifc

preferred, absolute values

P ₁ = 100-400 atU P ₂ = 5 atü below t »= 5 ^C C above t. ..

up to 100 ⁰ C
t ₂ = 5 ⁰ C below

Here, the CO ₂ is liquefied in B and therefore also a separation takes place

certain water content.

2nd case: Conditions:

_crit

^fc 2> preferred, absolute conditions:

P ₁ , P ₂ , tj = see case 1 t ₂ = 4O-8O ⁰ C higher than

_{Because t 2} > t _1, this case is only possible if the thermal load capacity

of the extract allows this.

3rd case: Conditions: P _g <P _krlt preferred, absolute values

= see case 1

4th case: Conditions:

crit preferred, absolute values:

P ₁ , P ₂ ,

= see case 1

For this, what was said under case 2 also applies v / egen t ₂ "> t ^.

The operating time of the process is between, depending on the parameters 1 and 8 hours.

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With the method according to the invention, more than 99 ° of the extractable fat content can be removed from the seeds; it is also possible to obtain fats that are almost completely free of water.

Examples :

600 g of coarsely chopped copra were in the plant according to the drawing processed under the conditions of case 3 as follows:

Gas: dry CO ₂ P. = 350 atii

Duration: 3 hours t ₁ = 50 ⁰ C

P ₂ = 65 atm

t ₂ = 50 ⁰ C result :

35 g of solid, whitish-yellow coconut fat were obtained. The residue was a dry, light brown, powdery mass. Analytical data: see summary table.

2. ■ '

600 g of sunflower seeds were roughly chopped and processed in the plant according to the conditions of case 3 as follows:

Gas: dry CO ₂ P, = 320 atm

Duration: h hours t. = 50 ⁰ C

Pp = 56 atm

t ₂ = 55 ° C ' Result :

148 g of a light yellow, clear oil with a pleasant odor were obtained obtain. A dry, crumbly mass remained as residue. Analytical data: see summary table.

600 g coarsely chopped soybeans are processed in the plant according to the conditions of case 3 as follows:

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Gas: dry CO ₂ · P- = 280 atm. Duration: 5 hours. t ₁ = ^ 5 ° C

P ₂ = 56 atm

t ₂ = 60 ⁰ C result:

112 g of a light yellow oil with a mild, pleasant aroma were obtained. A dry, light yellow, powdery mass remained as residue.
Analytical data: see summary table.

H.

450 g coarsely chopped peanut kernels were in the plant according to

processed the conditions of case 1 as follows:

Gas: dry CO ₂ P = 500 atm

Duration: 3 hours t- = 50 ° C

P ₂ = 56 atm

t ₂ = 20 ⁰ C result :

There were 235 g of a light yellow, due to the low water content slightly cloudy oil with a peanut aroma. A dry, light yellow, granular mass remained as the residue. Analytical data: see summary table.

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Analytical data:

ο co op cn ts>

D CO -O CD

rehearse l, 449o ====== / saponification
number VZ Acid number
SZ Iodine number
JZ Fat content
% in dry matter Water content
% Klarschmöiz-
ounkt ° C N) Copra, un
processed 62.5 3.6 27596 Coconut fat,
extracted 1,448-
l, 45o
: ====== :: 259 2.5 8.4 <o, l 25.2 Copra,
processed 1.4675 o, 5 8.8 Comparison
values from d.
Literature f.
Coconut oil
sunflowers
seeds, un
processed 25-262 - - 7-10
! SSCSSSaS äS SB SS! ! SSSSESaSBB =
25th 2.5 22-25 Sunflowers-
oil, extracted l, 466o-
-l, 468o 192 3.5 I3o <£ o, l sunflowers
seeds, be
is working o, 4 2.9 Comparison
values for suns
flower seed
oil from d. Lit. 188-
194 125-
14o. ·· -,

Analytical data (continued);

CO % ■■

Soybeans,
unprocessed isasrss: SSSSS3 ssssasssssss: 5 se: = !? a as ss S3 s rs: : ss s ssssrs ss ss: : s = s: ssssst3sc:
19.2 = X SS KS CSB CS S3 S3 S3 BSt SXS
3 _r 9 ss ε = sssasxactxxs & si SKsxs * Soybean oil,
extracted 1.4674 189 2.6 125 "C. 0.1 Soybeans,
processed 0.6 4.8 Comparison
values f.
Soybean oil ad
literature l, 465o-
l, 469o 189-
195 117-
141 ISS-SSSSS ^-1 Se:
54.4 = —S = SB3t: SSSB
2.7 LO Peanut kernels,
unprocessed 1.4644 * fo, 1 Peanut oil,
extracted I, 47o7 19o 1.9 93 2.2 5.5 Peanut kernels,
processed Comparison
values for
Peanut oil
adLit. l, 47oo
l, 47lo - 184-
195 84-95

-j cn co

Claims (5)

1. Process for the production of vegetable fats and oils, in particular of seed fats, by extraction with a solvent, characterized in that one deh seeds the fat by extraction with health-safe supercritical Removes gases and separates the fat from the resulting solution by changing pressure and / or temperature. 2. The method according to claim 1, characterized in that for the deposition, the pressure is _{lowered to values O ^ ■ t} and the temperature to a value ^ t. ., leaves. J5. Method according to Claim 1, characterized in that the pressure is lowered to values <P- .. and the temperature is lowered to a value <'ty _rit for the separation. 4. The method according to claim 1 to 3, characterized in that the supercritical gas used is COp. 5. The method according to claim 1 to 3, characterized in that the gases SFg, SCF ₇ , CHF ₂ Cl, CF ^ Cl, CF ₂ = CH ₂ , C ^ Fg, N ₂ O, fithane, ethylene alone are used as the supercritical gas or in mixtures with each other or with COp. - 10 - 209852/0879