DE2457846A1 - Protein contg, peanut powder prodn. - by salt-treatment, pressure-steaming and separating protein slurry from oil and aq. phases - Google Patents

Abstract

Ground-nut or peanut protein powder is prepd. by (1) treating the skinned peanuts in a satd. aq. salt soln. at a temp. and/or a time sufficient to remove the tannin. smell and the astringent bitter materials in the peanuts; (2) heat-treatment of the peanuts in water at >=90(100-120) degrees C, to remove salt absorbed in 1st process step, (3) heat-treatment under high press., pref. 15-20 min. in high pressure vessel with admission of an equiv. quantity of fresh water, so that the peanuts are comminuted to a slurry during steam admission, (4) strongly stirring the slurry with water, (5) allowing slurry to settle for a sufficient time, pref. 1-2 hrs. to form 3 phases, namely an upper oil-phase, an intermediate aq. phase and a bottom protein slurry phase, and separating the protein slurry phase, (6) centrifuging solids particles from protein slurry phase, washing the solid particles with water and spray-drying the solid particles, pref. at 170-200 degrees C, to obtain an ivory-white powder. The oil- and aq phases re recovered separately. Ivory-white to white powder is obtd. which is odourless and easily digested.

Description

Method of Making Peanut Meal The invention relates to to a process for the production of proteinaceous peanut flour from peanuts.

Since all over the world animal protein stocks are becoming increasingly limited are available, numerous attempts have been made to obtain protein from vegetable Products.

However, with the exception of soybean, none is sufficiently high in protein Known plant that would be used for this purpose.

Peanuts contain 30 to 32% protein. However, this is at 45 up to 48% crude fat, 3 to 4% water and 15 to 16% soluble, non-nitrogenous Associated substances, as well as 2 to 2.5% ash in the form of phosphoric acid and Alkali and 0.5 to 1% crude fiber.

The inventor previously described a method in US Pat. No. 3,829,589 described for the production of peanut flour, but the one produced by this process Peanut meal contains significant amounts of raw fat. This is a major disadvantage of the Peanut flour, which causes many difficulties, especially when it comes to the Only proteins should be added to food production and the high content on raw fat is disturbing.

Peanuts themselves are also used in food production, however, they are only subjected to roasting or pressing to produce oil will. Further processing is not known, especially not for Separation r of the protein. The reason for this may be that it is technically extraordinary it is difficult to peel, desdorise and separate the protein like this to carry out carefully that the protein is preserved largely undestroyed, with removal of tannin, other impurities and fat is particularly difficult are.

Process for the present invention is based on the object Manufacture of non-fat peanut protein flour to indicate that is odorless, essentially The ivory is free of fat, tannin and other impurities in the peanuts until it is white in color and is easy to digest after bothersome bitter, odor and color have been removed.

This is characterized by the method steps characterized in the claims achieved.

In the drawings, embodiments of the method according to present invention shown schematically.

According to the method shown in Fig. 1, the peanuts are after from which first the outer shells and then the skins have been removed, with a saturated or nearly saturated aqueous salt solution at a temperature from 20 to 50 C o, soaked for 5 to 5 minutes, then in water of over 9o0, preferably Ioo to 1200 heat treated and then together with a corresponding Put a lot of fresh water into a high pressure boiler, by doing by heat treatment under high pressure with steam supply for 15 to 20 minutes Peanuts are crushed into a pulp. If necessary, this porridge can be more suitable Way to be further crushed. The slurry is then transferred to a separation tank, adding an appropriate amount of fresh or hot water, stirring vigorously and then left to stand for one to two hours, whereby the pulp is divided into three phases stratified, i.e.

an upper oil phase, a middle water phase and a lower peanut protein phase. The lower peanut protein phase is means of the separator tank in the form of a pulp usual method taken, followed by centrifugation, for example by means of a centrifuge is done to get the peanut protein solids from the pulp, which are then washed with water and dried to flour. The drying preferably carried out by spray drying at a temperature of at least 17o0C, preferably 200 ° C.

The remaining two phases, i.e. the oil phase and the water phase, become deducted separately.

In the method shown in Fig. 1, the peanuts can after You have been soaked with the aqueous saline solution directly into the high pressure vessel without prior heat treatment.

For the extraction of the protein solids from the mentioned pulp you can a centrifuge method can be used. For the separation of the oil phase A suitable centrifuge is preferably used for the water phase. That Oil from the oil phase is purified to peanut oil, which becomes water from the water phase acidified by means of a mineral acid such as hydrochloric acid or sulfuric acid or an organic acid such as acetic acid, lactic acid and citric acid an acidic ion exchange resin or by means of electrodialysis to the water-dissolved Get protein in the form of a gel-like layer. That peanut protein is contained in fine protein flour, which is used for various purposes in the manufacture of food can be used and that also with the previously obtained Protein flour can be mixed. The water drawn from the system is fed back to the high-pressure boiler as the water to be fed.

The other method of the present invention is shown in FIG shown. After this process, the crushed peanut pulp, which is through the treatment in the high pressure vessel in the method explained with reference to FIG. 1 is obtained without using decantation as in the method of claim 1 brought to a pH of 4 to 5 by adding an acid, for example an inorganic acid such as hydrochloric acid and sulfuric acid or an organic one Acid such as acetic acid, citric acid and micro acid, preferably by means of hydrochloric acid in a separation tank to form three phases, i.e. the upper phase (oil phase), the middle phase (water phase) and the lower phase (protein pulp phase). The lower Phase (protein pulp phase) is separated and as described in FIG Process treated to obtain peanut protein flour.

The remaining liquid phase, which consists of the oil phase and the water phase is subjected to centrifuge treatment, around the oil phase to separate from the water phase. The separated oil phase is then by means of conventional Process Purified To Obtain Peanut Oil. On the other hand, the separated Water can be added back to the high-pressure boiler and used there.

If the acidifier used remains in the water and possibly exerts undesirable influence on the human body or the high pressure vessel or if it has an unexpected influence on the product, it must be neutralized or otherwise completely removed.

The reason for having the skinned peanuts with a saturated Soaked in aqueous saline solution is not only speeding up the removal of unwanted impurities, but also the removal of bitter and Odor # - and the reason that the peanuts that are in the saturated watery Salt solution have been soaked at temperatures above 9o ° in the high pressure vessel are heat-treated includes sufficient crushing of the peanuts and thus to facilitate the separation of the solid particles.

According to the method according to the invention, it is possible to use continuous Ways to get peanut protein flour that is off-white that extraordinary is easy to digest and odorless.

The invention will now be described in more detail on the basis of exemplary embodiments. In each case, peanuts are used that have been peeled and peeled, to remove the skins by leaving them at a temperature of 50 for 3 to 6 minutes heated until looOC and then skinned in a skinning machine have been.

Example 1 1 kg of peanuts whose skins have been removed become with a saturated aqueous salt solution at a temperature of 30 C for 3 minutes soaked for a long time, then transferred to a tank for tannin removal, with double that Amount of water is added, followed by a heat treatment at 1oo0 C for 20 minutes follows and after washing with water an addition of double the amount of water and This is followed by heating to 90 ° C. for 30 minutes in this tank. Then the heat-treated peanuts are washed with water and placed in a high-pressure double boiler introduced and while steam is being supplied, a corresponding amount of water is supplied, followed by heat treatment under pressure to obtain a slurry. The slurry is then transferred to a separation tank, using three times the amount of water is added and, after stirring vigorously, left to stand for one hour. The resulting lower phase (pulp phase) is withdrawn, with the fractionation the pulp phase is observed through an observation window. After a wash the pulp is spray-dried with water at a temperature of 2000C and it becomes obtained an ivory-white oil-free flour containing 80% peanut protein contains. The other ingredients in flour besides protein are fibers, carbohydrates, vitamins and moisture.

The water phase that has been separated from the oil phase becomes a protein set tank in which the water phase is adjusted to pH 5 by adding Hydrochloric acid is adjusted to precipitate the water-soluble protein that is separated and spray-dried into a flour. This flour then becomes the one previously obtained Flour added.

Example -2 According to Example 1, 2 kg of peanuts, whose thin Skins have been removed with a saturated aqueous salt solution at 40 ° C 2 Soaked for minutes in a tannin removal tank with double the amount transferred to water, followed by heat treatment at 110 ° C for 20 minutes, and after washing with water and adding twice the amount of water a heat treatment is carried out at 90 ° C for 30 minutes.

The peanuts treated with hot water are washed with water and transferred to a high-pressure double boiler and with a corresponding steam supply Added amount of water and heated under high pressure for 30 minutes to form a peanut pulp to obtain. The slurry is transferred to a separation tank and adjusted to pH 4.5 by addition adjusted by hydrochloric acid. After the solid particles of the pulp in the lower Phase settled, these particles are separated and washed with water the solid particles are spray-dried in order to obtain a flour, the more than 75% protein contains carbohydrates and vitamins while the rest and fibers and that is ivory-white in color. The one left behind Liquid, which consists of the water and the oil phase, is subjected to centrifugation exposed in a suitable centrifuge to separate the water from the oil. That The separated water is returned to the high-pressure boiler for further use.

Claims (13)

P. a t e n t a n s p r ü; ii c h e Process for the production of peanut protein flour, g e k e n n - marked by treating the skinned peanuts in a saturated aqueous salt solution one to remove the tannin, the smell and the astringent bitter substances in the peanuts sufficient temperature and time, heat treatment of the peanuts in water at a temperature above 90 °, around that in the first process step to remove absorbed salt, heat treatment under high pressure such that during The steam too drove the peanuts to be crushed to a pulp, stirring vigorously the pulp with water, allowing the pulp to settle for a sufficient amount of time three phases are formed, namely an upper oil phase, a middle water phase and a lower protein mixture and separation of the protein bi-phase, centrifugation the solid particles from the protein pulp phase washing the solid particles with Water, and spray drying the particulate matter to obtain an ivory white color Flour. 2. The method according to claim 1, characterized in that the heat treatment carried out under high pressure in a high pressure vessel for 15 to 20 minutes, an equivalent amount of fresh water being supplied. 3. The method according to claim 1, characterized in that the settling time 1 to 2 hours. 4. The method according to claim 1, characterized in that the spray drying step is carried out at a temperature of 170 to 2000C. 5. Process for the production of peanut protein flour, characterized by treating the skinned peanuts in a saturated aqueous salt solution one to remove the tannin, odor, and those found in peanuts Bitter substances at sufficient temperature for a sufficient time, heat treatment of the peanuts in water at a temperature above 900 to that in the first process step To remove absorbed salt, high-pressure heating of the heat-treated peanuts with the supply of steam and its comminution to a pulp, vigorous stirring of the pulp with the addition of water, allowing the pulp to settle for a time sufficient for the formation of three phases, namely an upper oil phase and a middle water phase and a lower protein pulp phase, separating the protein pulp phase, Centrifuge the solid particles from the protein pulp phase, washing the solid particles with water, spray-drying the solid particles to obtain an ivory-white flour Color, separation of the water phase from the oil phase, acidification of the water phase with an inorganic or organic acid or an ion exchange resin or means Electrodialysis to separate out the protein dissolved in the water phase of the deposited protein in the form of a gel-like layer, cleaning and spray drying the separated protein to obtain a water-soluble peanut protein and Mix the two peanut protein flour. 6. The method according to claim 5, characterized in that the heat treatment under high pressure in a high pressure vessel with introduction of an equivalent amount of fresh water for 15 to 20 minutes. 7. The method according to claim 5, characterized in that a settling time is used for 1 to 2 hours to form the arei phases. . Method according to claim 5, characterized in that the spray drying is carried out at a temperature of 170 to 2000C. 9. The method according to claim 5, characterized in that the used Acid hydrochloric acid, sulfuric acid, acetic acid, lactic acid or citric acid or is a mixture of these. 10. The method according to claim 6, characterized in that the water phase is fed back to the high-pressure boiler as fresh water after it has been separated off. 11. A process for the production of peanut protein flour, characterized by treating the skinned peanuts in a saturated aqueous salt solution one for the removal of the tannin, the smell and the astringent bitter substances heat treatment of the peanuts at a sufficient temperature for a sufficient time the peanuts in water at a temperature above 90 ° C to remove the in the first process step the absorbed salt, heating the heat-treated Peanuts under high pressure with steam until crushed to a pulp, setting the pH of the pulp to 4 to 5 by adding an acid such as hydrochloric acid, sulfuric acid, Acetic acid, citric acid and lactic acid to form three phases, one upper oil phase, a middle water phase and a lower protein pulp phase, Separation of the pulp phase, centrifugation of the solid particles from the pulp phase and washing the solids with water and spray drying the solid particles Preservation of a flour of ivory-white color. 12. The method according to claim 11, characterized in that the heat treatment is carried out under high pressure in a high pressure vessel, while an equivalent Amount of fresh water is supplied. 13. The method according to claim 12, characterized in that the water phase separated from the oil phase and fed back to the high-pressure boiler as fresh water will.