DE1058184B - Process for degumming vegetable oils - Google Patents

Description

Process for degumming vegetable oils The invention relates to a method for degumming vegetable 051e, e.g. B. of soybeans, cottonseed, Perilla, flaxseed, peanut, corn and wood oils, which give break-free oils be used for food and industrial uses involving vegetable Oils of the highest quality are required, especially suitable.

So far, break-free vegetable oils were almost exclusively made after the so-called "alkali cleaning" process, which mainly consists in the crude oil or the oil treated in water with an aqueous caustic alkali solution to wash. The "soap stick" created as a by-product, which is essentially consists of a soap mixture, neutral oil and water, but causes the loss valuable neutral oil, some of which is held in the soap stick and on the other hand is lost through hydrolysis.

In addition to this alkali cleaning, numerous other methods of producing nondestructive oils have been proposed. It is known from U.S. Patents 2,410,926 and 2,666,074 to convert oils by adding organic acids, e.g. B. of oxalic acid, maleic acid, etc., to degumming in solid or dissolved form. The method proposed in the present case is - as will be demonstrated - clearly superior to this known method.

According to the new process, the oil in question is treated with water for the purpose of degumming and then the aqueous component is separated from the oil, the oil with a small amount of at least one acid anhydride, namely acetic acid, propionic acid, butyric acid, according to the invention, prior to the separation of the aqueous component -, maleic acid, succinic acid, monomethylsuccinic acid or dimethosuccinic anhydride, is treated.

Compared to the alkali cleaning of vegetable oils, this one offers Invention has the following advantages: (1) The break-free oils can already be used during degumming can be obtained without further purification steps; (2) Fatty acids can be in a single Stage by distillation together with tocopherols and sterols during the odor removal be won; (3) the loss of neutral oil is much less; (4) that Odorless, nondestructive oil exhibits excellent taste and good taste Persistence on.

One of the unexpected features of the present invention resides in based on the fact that fracture-free oils are of good quality under normal conditions Can be made from raw vegetable oils that are neither partially purified have been left standing long enough for some of the slime to excrete could. On the contrary, the present process works better when it comes to cleaning Ordinary crude oils that are not allowed to stand or sit down or are used have been purified in any other way. It is of particular use in the treatment of soybean oil, because soy lecithin is the main lecithin of the Trade represents. It allows in an extremely economical way and in one stage the production of vegetable oils, which means in the treatment Show no breakage with heat and acid. You can of course also use mixtures of the acid anhydrides mentioned.

Basically one proceeds in such a way that one with the water degumming of the oil adding a small amount of one of the above acid anhydrides, the mixture is made Water, oil and anhydride for a suitable time at elevated temperature and stir then centrifuged to separate the aqueous phase.

According to a particular embodiment, the oil with a low Amount of acid anhydride before adding the water for degumming mixed and the resulting aqueous phase separated from the unbroken oil phase.

Another embodiment provides that the oil with a short time mixed with a small amount of the acid anhydride and then proportionately mixed with the degumming water for a long time and the emerging aqueous phase is separated from the unbroken oil phase.

Finally, however, the oil can also be used at the same time as the acid anhydride and the water to be treated.

The anhydride can therefore either be added (1) to the degumming water, (2) to the C51 or (3) to the mixture of C51 and degumming water. In the treatment of e.g. B. raw soybean oil according to the invention, the 01 is mixed for at least 1 minute with - based on the weight of the oil - at least 0.05% of the acid anhydride and then at a temperature between 40 and 100 ° C, preferably between 60 and 85 ° C , with - based on the weight of the oil - at least 1.51) / o water mixed for at least 5 minutes. The duration of the treatment is not decisive, but should be as short as possible for economic reasons.

The following examples illustrate the invention. Example 1 1500g of a crude solvent-extracted soybean oil obtained after the Official Method Ca 10-40 of the American Oil Chemists Society (after G a r d n e r) contained 0.5% breakage were heated to 60 ° C. 1.5 g were added with stirring Acetic anhydride given. After 5 minutes, 22.5 g of water were added. The mixture was then stirred for 15 minutes, during which time the temperature increased to 85 ° C became. The mixture was then in a centrifuge for 15 minutes at 1800 rev / min. centrifuged to separate the aqueous mucus phase from the C51. The C51 showed then no break in the heat and Gardner fracture tests. During the Gardner exam the C51 got brighter. It was then made in the usual way with bleaching clays and more active Coal bleached and then odorless in a known manner with steam at 225 ° C / 4 mm made. Before the odor was removed, the oil had a free fatty acid content 0.27%; after deodorization 0.008%. 2.5 g of the fatty acids were put together obtained with tocopherols and sterols in the condenser. It can prove to be expedient prove to add an aftertreatment agent, e.g. B. Sorbitol, Citric acid or the like to be added in order to improve the shelf life of the oil.

The C51 thus obtained was a first quality edible oil; it tasted even better than an edible soybean oil obtained by alkali-purifying the water-degummed crude oil and then rendering it odorless. The lecithin obtained by drying the gum was somewhat more fluid than the lecithin usually obtained by water degumming of soybean oil. Example 2 It should be determined whether the acetic anhydride used in Example 1 merely acts like the corresponding acid in the process. The procedure of Example 1 was repeated, except that 3 g of acetic acid were used instead of 1.5 g of acetic anhydride. (The amount of acetic anhydride used in Example 1 would theoretically correspond to 2.55 g of acetic acid. The 3 g used here were therefore above the theoretically required amount.) This attempt failed because with the acetic acid only a partially degummed oil was obtained, which was cloudy and did not fade when heated in the Gardner test. The same result was obtained when the experiment was repeated with 2.55 g of acetic acid. This clearly shows that the anhydride plays a very special role in the cleaning process and does not act like the corresponding acid. Example 3 The procedure of Example 1 was repeated, except that instead of the soybean oil obtained by solvent extraction, an oil obtained by the pressing process was used. The obtained centrifuged C51 was light and bleached well when heated. It was break free. The 01 was comparable after bleaching and deodorization in quality to that obtained by the method of Example 1 C51. Example 40 A mixture of 22.5 g of cold water and 2 g of acetic anhydride was added to 1500 g of a crude solvent-extracted soybean oil. The mixture was stirred, held at 60 ° C. for 20 minutes and then centrifuged. The oil was light in color and free from fractures by the Gardner test. When rendered odorless and bleached by the procedure described in Example 1, the C51 was a first grade edible soybean oil. Example 5 To 1500g of crude extracted soybean oil was added 22.5g of water at 60 ° C. After the mixture was stirred for 5 minutes, 1.5 g of acetic anhydride was added. The stirring was then continued for 20 minutes and the resulting mixture was centrifuged. According to the Gardner test, however, this C51 was not completely free of breaks.

Example 6 In a repetition of Example 5, 2 g of acetic anhydride were used. According to G ardner, the oil obtained was free from breakage and, after bleaching and smelling of mustard, gave an edible soybean oil of first quality. Example 7 To 1500 g of raw extracted soybean oil was added 22.5 g of water at 80 ° C. The mixture was then stirred for 5 minutes, 3 g of acetic anhydride were added and stirring was continued for 20 minutes. The obtained after centrifugation of the mixture was 01 ardner break free after G and gave after bleaching and deodorizing an edible oil first quality. Example 8 The procedure of Example 1 was repeated, only the entire degumming was carried out at 40 ° C. According to G ardner, the oil obtained after centrifugation was free of breakage and after bleaching and odorlessing gave an edible C51 of first quality.

Example 9 The procedure of Example 1 was repeated except that the entire degumming was carried out at 75 ° C. After centrifugation that was obtained oil after Gar d ner break free and yielded after the bleaching and odorless a first quality edible soybean oil.

Example 10 The procedure of Example 1 was repeated except that the entire degumming was carried out at 95 ° C. After centrifugation that was Z51 according to G a r d ner r free from breakage and yielded after bleaching and odorlessing a first quality edible 01.

Example 11 This example was similar to Example 1, except that a raw extracted soybean oil with 0.31% fraction processed. That after centrifugation The Z51 obtained was free from fractures according to Gardden and gave after bleaching and Odorless a first quality edible 01.

Example 12 This example was also similar to Example 1, except that they were used here 1500 g of raw extracted soybean oil with 0.21% breakage is processed. After this After centrifugation, the oil obtained was not free of breakage after G a r d n e r, but rather cloudy.

Example 13 Using 3.0 g of acetic anhydride, Example 12 repeated. After centrifugation, the oil was free from breakage according to G a r d n e r and when bleached and odorless, resulted in a first quality edible soybean oil.

Example 14 To 1500g of raw extracted soybean oil was added at 60 ° C added 1.5 g of powdered succinic anhydride with stirring. After 15 minutes 22.5 g of water were added; then stirring was continued until the temperature was reached Had reached 80 ° C. Stirring was then continued for a further 20 minutes. Then it became The mixture was centrifuged to separate the slime. The 01 received was after Gardner break free and after bleaching and odorlessing gave an edible soybean oil first quality. Example 15 When example 14 was repeated, only 0.75 g of powdered succinic anhydride was used. The Z51 was after centrifugation break-free and after bleaching and rendering odorless resulted in an edible oil first Quality.

Example 16 This example was the same as Example 14 except that the water became added before succinic anhydride. That obtained after centrifugation 01 was free of breakage and after bleaching and odorlessing resulted in an edible oil first quality.

Example 17 This example was similar to Example 14, except that 1.5 g of maleic anhydride were used instead of the succinic anhydride. The obtained after centrifugation was 01 break free and gave after bleaching and deodorizing an edible 01 first quality.

Example 18 This example was similar to Example 1, except that 1.5 g of propionic anhydride were used instead of acetic anhydride. The centrifuged 01 was break free and revealed after bleaching and deodorizing an edible 01 first quality.

Example 19 This example also corresponded to Example 1, only were instead of acetic anhydride, 1.5 g of butyric anhydride were used. The centrifuged Z51 was nondestructive and after bleaching and deodorization gave an edible Z51 first quality.

Example 20 A solution was added to 1500 g of crude extracted soybean oil of 3.2 g of maleic anhydride in 20 cc of water. The mixture was 15 minutes stirred at 60 ° C and then centrifuged. A break-free Z51 was obtained, which when bleached and odorless resulted in a first quality edible oil. Example 21 This example was similar to Example 20, but instead of maleic anhydride 3.2 g of succinic anhydride used. The centrifuged oil was free of breakage and yielded after bleaching and odorless, an edible 01 of first quality.

Example 22 This example was also similar to Example 20, except that they were used 3.2 g propionic anhydride were used instead of maleic anhydride. The centrifuged 01 was free of breakage and after bleaching and odorlessing resulted in an edible 01 "first Quality.

Example 23 0.4 g acetic anhydride was added to 400 g of a completely crude linseed oil given with stirring. After 5 minutes, 2 grams of water was added, followed by the mixture Was stirred at 60 ° C for 15 minutes. After it had cooled to 40 ° C, was centrifuged the mixture. The Z51 was break free.

Example 24 This example was similar to Example 23, only instead of the Acetic anhydride maleic anhydride is used. That obtained after centrifugation Flaxseed oil was break free.

Example 25 To 1000 g of a crude corn oil obtained by pressing 1 g of acetic acid was added. Then the mixture was heated to 70 ° C and below Stirring mixed with 30 g of water. After holding at 70 ° C for 45 minutes, the Centrifuged mixture. The result was a bright Z51 that was free of breakage.

Example 26 This example was the same as Example 25, only instead of of the corn oil used 1000 g of raw cottonseed oil. The centrifuged cottonseed oil was break free.

Example 27 This example again corresponded to Example 25, but were 1000 g raw peanut oil used instead of corn oil. The centrifuged peanut oil was break free.

The method of the present invention can be carried out in known devices carried out either as a batch or as a continuous process will. There have also been numerous attempts to the determine permissible and preferred working conditions. To these attempts Soybean oils with various breakage levels were used. A whole raw soybean oil, as it comes from the solvent extraction process, exhibits a fracture content between 0.48 and 0.70%. To ensure the best conditions for the generation of break-free To determine oils from partially degummed crude oils, oils with 0.56, 0.31, 0.21 and 0.13% breakage made. All of these oils became nondestructive oils according to of the invention using acetic anhydride as a degumming agent made in good quality. From these experiments and the above examples goes show that the process according to the invention for the production of fracture-free oils from completely raw vegetable oils and also from partially degummed vegetable oils can be used can.

A number of experiments were made to determine approximately the minimum amount of acid anhydride required to degumm a whole crude soybean oil to a nondestructive oil. The table summarizes the results obtained by treating seven 500 g samples of crude extracted soybean oil with various amounts of acetic anhydride at 60 ° C. In each case, after the acetic anhydride addition, the temperature of the oil sample was increased from 60 to 75 ° C. in 5 minutes with stirring, after which time 3% water (ie 15 g) was added. The temperature of the mixture was kept between 60 and 75 ° C. for 15 minutes with vigorous stirring. Each sample was then centrifuged in centrifuge beakers for 15 minutes at 1,800 revolutions per minute. After separation of the slime deposits, the breakage of each sample was determined according to Gardner. Acetic anhydride results 0/0 0.4 break-free 0.3 break-free 0.2 break-free 0.1 break-free 0.08 break free 0.06 break free 0.04 not break free From these results it can be seen that, under the conditions used, 0.06% acetic anhydride is sufficient to achieve a break-free oil. Experience has shown, however, that about 0.1% anhydride is the minimum amount that is sure to result in a break-free oil. It has been found that the amount of anhydride depends on the temperature and the amount of breakage in the crude oil. For example, very crude soybean oils with 0.1% acetic anhydride were obtained at 60 and at 80 ° C., while 0.2% acetic anhydride was required at 40 ° C. Partially degummed soybean oils with 0.31% breakage gave break-free oils at 60 ° C. with 0.1% acetic anhydride; at 40 ° C, however, at least 0.2% of the anhydride was also required here. Crude oil with 0.210 / 0 or less breakage could not be made break free with less than 0.2% acetic anhydride at any temperature.

A number of tests were carried out to see if the 1.5% water, based on the weight of the oil, in the known water degumming process sufficient, also sufficient if acetic anhydride or another anhydride according to of the invention is used. In general, it is best to increase the amount of water to a minimum, as increased amounts of water increase oil losses and also reduce the acetone-insoluble content of the dried lecithin. It has been found that crude oil with 0.31 or more 0/0 fraction according to the invention at 40 to 100 ° C using 1.5% water, based on the weight of the oil, can be made break-free. Crude oil with 0.21% or less breakage requires more, z. B. 3.0% degumming water. Larger amounts of water generally reduce especially at temperatures below 60 ° C, the required contact time.

Appropriate tests showed that only very short, in the order of magnitude 1 minute contact times for the acid anhydride and oil before addition of the degumming water are required if the sequence just mentioned of the addition is adhered to. Accordingly, the anhydride should, if minimum quantities to be used by him, to which oil should be added before the water is added, if degumming is to be carried out above 40 ° C. You can break free Obtain oil at a higher temperature by adding the water to the oil beforehand, if increased amounts of acid anhydride are used. It doesn't seem like a particular benefit lying in adding the water to the oil before the anhydride, while before When the anhydride is added to the oil, the contact time between the reagent and the oil can be very short can and changes in this contact time, if at all, very little Seems to have an effect if the anhydride is used before the addition of the degumming water is admitted.

It has been found that when the acid anhydride, which acts as a degumming agent, is added to the oil before the degumming water, the temperature of the oil can be within a wide range of no essential importance, i.e. the reagent can either be added to the cold oil and the oil then heated to degumming temperature or the oil can be heated to degumming temperature before the anhydride is added. Apparently the temperature at which the anhydride is added or contacted with the oil is not particularly important, unless the anhydride is added after the degumming water has been added.

The investigations also showed that the contact times between Entschleimungswasser and 01 with the temperature of the crude oil and the leakage amount in the crude oil vary. For example, in the case of crude soybean oil with a high level of fragility, when 3.0% degumming water was used, 15 minutes of contact time were required at 20 ° C, while when only 1.5 a / o degumming water was used, 30 minutes of contact time were required at the same temperature to obtain a break-free oil. At a temperature of 60 ° C or above, if 1.5% degumming water was used, 5 minutes was the minimum contact time to obtain a break-free oil if the other conditions remained the same. For crude soybean oil with 0.21% or less breakage, at least 3.0% degumming water was necessary and at least 30 minutes of contact time to obtain a break-free oil.

Visual inspection of the slime deposition appears to show that an extension of the contact time between water and 01 about the theoretical minimum time up to a practical maximum time the distance the slime eased by centrifugation. This judgment is based on the Appearance of the slimes when they are deposited on the bottom of the centrifuge beaker. If only a minimum contact time was used, the slime deposition appeared in certain layers, resulting in a non-uniform rate of deposition revealed. When the contact times were increased, the slimes settled in one uniform layer.

The preferred working conditions for degumming a particular Vegetable oils with an acid anhydride according to the invention can easily be obtained by simple Preliminary tests can be determined, but this should be unnecessary in most cases.

In analogy to Example 2, other acid anhydrides were also used as Acetic anhydride with the corresponding acids in their effect as a degumming agent compared: Were 1500 g of crude oil according to the invention with 1.5 g of maleic anhydride, propionic anhydride or succinic anhydride (that is 0.1%) treated as a degumming agent, the Gardner fracture test was negative; the oil was break free, shiny and bleached well in the warmth. Were the 1500 g of crude oil with 1.8 or 3.0 g of maleic, propionic or but succinic acid (that is 0.12 or 0.2%) treated as a degumming agent, thus the Gardner fracture test was positive; the oils were not fracture-free, but rather cloudy and showed no heat bleaching. So the treatment with acid anhydrides is clearly superior.

Claims (6)

PATENT CLAIMS: 1. Process for degumming a vegetable oil, in which the oil is treated with water and then the aqueous component of the oil is separated, characterized in that the oil before the separation of the aqueous component with a small amount of at least one acid anhydride, and acetic acid, propionic acid, butyric acid, maleic acid, succinic acid, monomethylsuccinic acid or dimethyl succinic anhydride. 2. The method according to claim 1, characterized in that the 01 with a small amount of the acid anhydride mixed before adding the water for degumming and the resulting aqueous phase is separated from the break-free oil phase. 3. The method according to claim 2, characterized characterized in that the oil is briefly treated with a small amount of the acid anhydride mixed and then with the degumming water for a relatively long time mixed and the resulting aqueous phase separated from the unbroken oil phase will. 4. The method according to claim 2, characterized in that the 01 at least 1 minute with - based on the weight of the oil - at least 0.05% of the acid anhydride mixed and then at a temperature between 40 and 100 ° C with - on the weight of the oil - at least 1.5% water is mixed for at least 5 minutes. 5. The method according to claim 4, characterized in that the temperature is between 60 and 85 ° C. 6. The method according to claim 1, characterized in that the Oil is treated simultaneously with the acid anhydride and the water. Into consideration drawn pamphlets: U.S. Patents Nos. 2,410,926, 2,666,074; Stapler- Schönfeld, "Chemistry and Technology of Fats and Fat Products", Vol. 1I, 1937, p. 22nd