Process for obtaining pure lecithin (de-oiled) from crude oil obtained during the production of vegetable or animal fats and oils

Abstract

1. Process for obtaining pure lecithin (de-oiled) from crude oil obtained during the production of vegetable or animal fats and oils 2.1. According to the state of the art, water is added to the oil in a precisely measured quantity while stirring, causing the lecithin contained in the crude oil to swell, separate, and dry. For some applications of lecithin, the oil is largely removed. The reduction of the oil content of the crude lecithin is achieved by extraction with solvents or solvent mixtures. These measures are very complex. In particular, the removal of residual solvents required in the final stage is very time-consuming. Furthermore, the lecithin is exposed to elevated temperatures again during this process step. The new process is intended to enable the production of pure (de-oiled) lecithin without the further use of organic solvents or multiple temperature stresses. 2.2. Pure lecithin (de-oiled) is directly formed from the crude oil obtained during the production of vegetable fats and oils by adding H2O and controlling the temperature appropriately. 2.3. Production of pure lecithin (de-oiled).

Description

[0001] Lecithins belong to the class of compounds known as phosphatides, which are found in almost every plant and animal material. They can be obtained in abundant quantities, especially from soybeans, sunflower seeds, and rapeseed, but suitable crude oils can also be produced from egg yolk and brain matter, corn, and, for example, safflower. The element phosphorus is present in phosphatides as phosphate esters.

[0002] Soybean oil, rapeseed oil, sunflower oil, and occasionally other vegetable oils are particularly delecithinized after extraction. They contain the lecithin in colloidal form. According to the state of the art, water is added to the oil in precisely measured amounts while stirring, and the lecithin contained in the crude oil is swollen. The emulsion-like mixture is separated in a separator. The delecithinized crude oil leaves the separator as the lighter phase. The aqueous, sludgy phase contains the lecithin. The viscous crude lecithin is obtained from the aqueous, sludgy phase by drying in a vacuum dryer.

[0003] Industrially produced soy lecithin is particularly important in terms of both quantity and composition. The crude lecithin obtained from crude oil extracted during soybean processing consists of approximately one-third oil and approximately two-thirds acetone-insoluble components, primarily phosphatides.

[0004] In some lecithin applications, it is desirable to largely remove the oil. Lecithins are used extensively in food processing and in pharmaceutical and cosmetic preparations. Therefore, high standards are placed on the quality of lecithins, especially with regard to their physiological safety.

[0005] The oil content of crude lecithin is reduced by extraction with specific solvents or solvent mixtures. These processes are very complex. In particular, the removal of residual solvents required in the final stage is very laborious. Furthermore, the lecithin is subjected to further stressful conditions, such as elevated temperatures, during this process step.

[0006] It is also known that pure lecithin can be produced using supercritical gases (DE 30 11 185 A 1), by contacting crude lecithin with a gas as an extraction agent under supercritical pressure and temperature conditions in an extraction step. However, improved processes (DE 3411755; EP 0 156 374 A2) also represent two-stage processes for the production of pure lecithin.

[0007] The invention relates to a process for obtaining pure lecithin (deoiled) from the crude oil obtained during the production of vegetable fats and oils by means of a suitable temperature control, wherein H2O is used as reagent under conditions in which the pure lecithin is formed directly.

[0008] This invention is directed to a process for obtaining pure lecithin that does not have the aforementioned disadvantages. This is achieved by the process according to the patent claims. Essentially, the present invention is based on a process in which pure lecithin is produced directly from crude oil by treatment with H2O at a temperature below 10°C.

[0009] For this purpose, the crude oil is cooled to a temperature below 5°C. Since the viscosity of the crude oil increases at lower temperatures, it is recommended that the crude oil temperature should not fall below -5°C for ease of handling. Water at 5°C or ice water is added to the crude oil, which has a temperature of 5°C or below, in precisely measured quantities while stirring, and the lecithin contained in the crude oil is precipitated. The mixture of substances is separated at a temperature below 10°C. The pure lecithin is obtained as a solid phase. The residual moisture is removed by drying in a suitable process, such as drying in a vacuum dryer or by freeze-drying. The pure lecithin obtained from extracted crude oil during soybean processing using this process consists of more than 90% components that are insoluble in acetone, primarily phosphatides.

[0010] Hydrogen peroxide solution can also be added to the water if the deoiled lecithin has special microbiological requirements. In this case, the water must be removed by drying at temperatures below 60°C in a vacuum to achieve a peroxide value that meets food safety requirements.

[0011] This production process is of particular importance, especially with regard to its physiological safety, since the crude oil is already produced using processes that do not involve (organic) solvents. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 30 11 185 A

[0006] DE 3411755

[0006] EP 0 156 374 A2

[0006]

Claims

[1] Process for the extraction of pure lecithin from the crude oil obtained during the production of vegetable oils by extraction with the aid of water, characterized by Water at a temperature below 10°C, preferably 0 to 5°C, is used to separate unswollen lecithin from the crude oil cooled to a temperature below 10°C, preferably 5 to -10°C, thereby obtaining pure lecithin from crude oil in a single-step process. This allows pure lecithin to be produced from the liquid lecithin without the use of organic solvents or supercritical gases. [2] Process for the extraction of pure lecithin from the crude oil obtained during the production of cold-pressed vegetable oils with the aid of water, characterized byWater at a temperature below 10°C, preferably 0 to 5°C, is used to separate unswollen lecithin from the crude oil cooled to a temperature below 10°C, preferably 5 to -10°C, thereby obtaining pure lecithin from crude oil in a single-step process. This allows pure lecithin to be produced without the use of organic solvents or supercritical gases. [3] Process for the extraction of pure lecithin from the crude oil obtained during the production of warm / hot-pressed vegetable oils by means of water, characterized by Water at a temperature below 10°C, preferably 0 to 5°C, is used to separate unswollen lecithin from the crude oil cooled to a temperature below 10°C, preferably 5 to -10°C, thereby obtaining pure lecithin from crude oil in a single-step process. This allows pure lecithin to be produced without the use of organic solvents or supercritical gases.