DK142934B - PROCEDURE FOR FRACTIONING OF GREEN LEAVES - Google Patents

Description

will) (11) PUBLICATION 142934 DENMARK (ευ int.ci.3a 23 j 1/00 § (21) Application No. 2649/72 (22) Filed on 26 May 1972 (24) Running day 26 May 1972 (44) The application presented and the petition published on 2 March 1 981 THE DIRECTORATE FOR 4.

PATENT AND TRADE MARKET (30) Priority requested from May 28, 1971, 147947, us (71) GEORGE 0. KOHLER, 2259 Tamalpais Avenue, El Cerrito, California, US: EMANUEL M. BICKOFF, 26 Binnacle Hill, Oakland, California , US.

i72) Inventor: Same.

(74) Plenipotentiary in the proceedings:

The company Chas. Hude.

(54) Process for fractionation of green leafy plants.

The invention relates to a method for fractionating green leaf plants to obtain proteins for feed purposes.

Lucerne is the main crop for feeding in the United States and is therefore suitable for use as plant material in the process of the invention. However, as a plant material, leafy green crops can generally be used, for example grasses, lespedeza, clover, alfalfa and similar common fodder plants and other green foliage plants such as lettuce, cabbage, kale, pea or bean plant. 3 oats, celery plants, beets and the like, which are grown for use as cattle feed or are available as waste or by-products from companies which pack or process such plant material.

Lucerne is a well known source of valuable nutrients including proteins, carotene (provitamin A), lipids, sugars, mineral salts, unidentified growth factors, etc. Methods for separating some of these components have already been proposed, which methods can be used to produce products which is suitable as livestock feed.

From the specification of U.S. Patent Application No. 883,544, a method for fractionating the alfalfa is known, which, among other fractions, results in a protein concentrate. This product is valuable as an energy-rich animal feed, especially poultry. The product has a high content of proteins, but it also contains significant amounts of other substances, such as chlorophyll and other pigments.

British Patent No. 705,369 discloses a process for the preparation of animal feed in which vegetable or animal material is processed to produce proteinaceous liquids by mechanical compression agents by which the cellular structure is degraded and a juice obtained which is separated. The remaining fibers or the remaining tissue are then washed to extract the protein content and the resulting washing liquid, with or without the juice obtained initially by compression of the raw material, is heat treated to flocculate the proteins which are then separated, for example by filtration. The flocculation can be carried out by heating to at least 60 ° C, for example 80 ° C, and the liquid from which the proteins are removed can be returned and used for leaching of proteins from fibrous material from which the juice is removed by the mechanical compression treatment.

Hereby, the vegetable proteins are precipitated at once, and therefore, by this known method, it is not possible to make a differentiated separation of the various proteins according to the purpose of use, either cytoplastic proteins, ie. colorless proteins, or chloroplastic proteins, i.e. pigmented proteins.

SUMMARY OF THE INVENTION The present invention aims to provide a method of the above-mentioned type by which differential precipitation is possible and by which the green leaf plants are pressed after any pre-treatment to form a juice and a press cake, after which the juice is heat treated. The process is characterized in that the juice is heated to a temperature of 55 to 70 ° C over 0.6 seconds, kept at this temperature for 0-20 seconds and cooled, whereupon the agglomerate formed by chloroplast proteins, chlorophyll, carotenoids and lipids is centrifuged. and the agglomerate is optionally heated for approx.

1 minute to approx. 80 ° C.

As plant material, alfalfa can be used and protein fractions containing either chloroplastic or cytoplastic proteins can be obtained.

In a convenient embodiment of the process according to the invention, the plant material is mixed with a sulphite source before pressing.

By the addition of such antioxidant, a reduced degradation of carotenoids is obtained.

Furthermore, it is advantageous in the method according to the invention before setting the plant material to adjust this to a pH value of approx. 7 to approx. 11 by addition of an alkalizing agent. By adding an alkalizing agent, it is achieved that a greater amount of protein will be transferred from the plant material to the green juice.

By heating the formed agglomerate to ca. 80 ° C for approx. 1 minute, the centrifugate is obtained from a hydrophilic jelly mass to a water-giving, quark-like consistency, after which the mass can be easily pressed to reduce the moisture content.

The process according to the invention can in principle be divided into the following main operations: I. Formation of a green juice (L-1). In this working step, a dried plant material (fraction A) can also be obtained which can be used for livestock feed.

II. Separation of a fraction B from the green juice (L-1), Fraction B is a product containing the chloroplastic proteins, chlorophyll, carotene, xanthophyll and other carotenoids as well as lipids.

It is valuable as livestock feed because it has a low content of fiber and a high content of protein, carotene and xanthophyll. The remainder of this process step is designated as clear juice (L-2), III. Separation of a fraction C from the clear juice (L-2). The fraction C is the main product of the process of the invention and contains the cytoplasmic proteins derived from the original alfalfa. It is essentially free of chlorophyll, carotenoids, lipids and bitter substances, as well as other undesirable flavor components.

The remainder of this process step is referred to as brown juice (L-3). It can be concentrated to obtain a syrup (fraction D) useful for livestock feed.

The invention will be explained in more detail below with reference to the drawing and using the alfalfa as an example of useful plant material,

Operation I: Manufacture of green juice.

The starting material for the fractionation is fresh green alfalfa, preferably in chopped form. According to customary farming practices, alfalfa is harvested when harvested. This usually chopped green plant material is selected as the starting material in the process of the invention. The fresh green material is introduced into a mixer 1, which may, for example, be a container with a mixing screw or a rotating drum. The mixer 1 is advantageously used for incorporating desired additives into the lucerne mass, the preferred additives being water or brown juice (L-3) as well as an alkalizing and / or reducing agent such as sodium metabisulfite, ascorbic acid or ethoxyquin. The effect of these additives is discussed later in the description.

After the mixing step, the green lucerne material is freed from juice by being passed through a press 2 with or without prior grinding, which may, for example, be a set of conventional sugar cane rolls. Other appliances which can be used for the juice extraction are screw presses or oil presses. As the aim is to get as much juice as possible out of the lucerne, the plant material can be repeatedly passed through a single set of press rolls or alternatively pass through a group of several sets of press rolls. The plant material obtained by a single pressing can advantageously be mixed with an additional amount of additives before being fed to the next set of press rolls.

5 142934

In this sapirification operation, a green juice fraction (L-1) and a fiber cake press cake are obtained. This press cake will generally have a moisture content of approx. 65-75%. The quantity ratio of juice to press cake will depend primarily on the moisture content of the starting material. In general, 100 kg of green alfalfa results in (a) about 50 to 60kg press cake and (b) a total amount of juice of approx. 40-50 kg and the amount of liquid (water or brown juice) added during the mixing step.

The press cake is passed through a drying apparatus 3 which can take the form of a rotary kiln, which is usually used for lucerne drying, thereby obtaining a dried product, referred to herein as fraction A and being a valuable cattle feed.

When using a high quality alfalfa harvested in Northern California, fraction A (on a dry matter basis) contains the following components:

Protein x 23% xxx

Fat 4%

Fiber 23%

Ash 10% NFE xx 40%

Carotene 330 mg / kg

Xanthophyll 770 mg / kg x Nitrogen content x 6.25 xx Nitrogen-free extract (mostly carbohydrates), as a difference, xxx Certainly for typical alfalfa obtained during commercial operation, the protein content will be several percent lower.

It has been mentioned before that certain additives can be incorporated into the lucerne in mixer 1 before pressing. It has been found that in case an alkalizing material is added, a greater amount of protein will be transferred from the plant material to the green juice. This is desirable as it means that a larger amount of protein will be formed in the following operations when fractions B and C are isolated. As alkalizing material may be used ammonia, ammonium hydroxide or sodium or potassium hydroxides or carbonates. Usually, the alkalizing agent is added in an amount such that a pH of 7 to 11 is obtained.

142934 6

In use, the alkalizing agent is preferably dissolved in water and the resulting aqueous solution is mixed with the lucerne. Addition of water is also useful for increasing the transfer of protein from the plant tissue to the green juice. Instead of water you can use the brown juice (L-3) which remains as a residue from the working step III. By continuously carrying out the process according to the invention, for example, a portion of the brown juice of L-3 can be continuously returned to the mixer 1. If water (or brown juice) is used as an additive, it is preferably used in an amount of approx. 1-3 kg per kg of lu = cores. However, much larger amounts can be used, for example 10 kg per day. kg of alfalfa.

Various materials can be incorporated into the lucerne during juice pressing if desired. For example, a conventional antioxidant may be added to reduce the degradation of carotenoids. For this purpose, any known antioxidant useful for the preservation of carotenoids in alfalfa or other feed materials can be used. Typical compounds of this category are those disclosed in United States Patent Nos. 2,562,970, 2,611,703, 2,651,572, 2,686,124, and 2,771,962, a preferred example being 6-ethoxy-2,2,4,4-. trimethyl-1,2-dihydroquinoline, commonly known as ethoxyquin. Only a small amount of antioxidant is needed, approx. 0.01% to 0.5%, based on the lucerne dry weight.

Other possible additives are sodium metabisulphite and ascorbic acid.

Addition of sodium metabisulphite or generally any sulphite source is preferred. Examples of such sources include ammonium sulfite, sodium sulfite, sulfur dioxide gas and sulfuric acid. However, it should be noted that the weight amount of such bisulfite additives should be less than the equivalent of 1% sodium bisulfite. Such additives are preferably added before the addition of the alkalizing agent and before the first pressing 2. However, such addition can be done at any time before heating in the heaters 4 and 14.

Another way to increase the transfer of proteins from the plant tissue to the green juice is to reduce the size of the alfalfa pieces. This is conveniently done by equipping the mixer 1 with rotating blades or the like, which produces a comminution of the plant parts as they come into contact with the water (or brown juice) containing the alkalizing agent. Alternatively, the lucerne may be ground before it is fed to the mixer 1. For best results (maximum transfer of proteins to the juice), the grinding is performed when the lucerne is mixed with the additives in the mixer 1.

Example 1.

This example illustrates how an increase in pH promotes the transfer of proteins from alfalfa tissue to the green juice.

Twenty-five gram portions of freshly chopped alfalfa were each mixed with 250 ml portions of water, and the pH was adjusted (by addition of hydrochloric acid or sodium hydroxide) to a certain level as indicated below. The mixtures were mixed for 2 minutes and then separated into their components of fibrous plant material and green juice, the latter being analyzed for nitrogen content.

The working conditions used and the results obtained are given below.

Nitrogen content in green juice p_H_% total-N in alfalfa_ 4.0 18.6 4.7 25.4 5.3 48.7 5.8 x) 65.1 9.6 70.4 10.7 74.9 11.4 81, 0 X)

The natural pH of the juice.

Example 2.

This example illustrates how disintegration of the lucerne enhances the transfer of proteins from the lucerne tissue to the green juice.

25 gram portions of freshly chopped alfalfa were mixed with 250 ml portions of water and the pH was adjusted to 8 with sodium hydroxide. The blends were then subjected to a disintegrating effect, subjected to a rotating blade which varied in cutting effect on the alfalfa pieces for varying periods of time. The mixtures were then separated into their components of fibrous plant material and green juice, and the latter analyzed for nitrogen content.

The working conditions used and the results obtained are given below.

Duration of disintegrants = Nitrogen content in green juice effect min_% total-N in alfalfa_ 1 45 2 68 4 86

Step II. Separation of chloroplastic material.

(Fraction B).

The green juice (L-1) from the press 2 was used as the starting material for this working step. It is desirable that no significant delay occurs between the formation of the green juice in the pressing stage and the beginning of step II, since hydrolysis of protein occurs rapidly once the cells are broken. This hydrolysis, which is triggered by proteolytic enzymes, can be suppressed by appropriately adjusting the juice's pH to the range above 8.0. In this step (II), the green juice is treated to selectively remove chloroplastic proteins, chlorophyll, carotenoids and lipids, while the cytoplasmic proteins remain in solution.

The green juice is then passed through the heater 4.

A steam supply heater capable of heating the green juice to 70 ° C in 0.6 seconds was used. Samples of the green juice were thereby heated to various temperatures of 55, 60, 65 and 70 ° C. In some cases, the hot juice was immediately cooled to a temperature below 40 ° C. In other cases, the juice prior to cooling was stored in a warm state for a specified time. In each case, the chilled product was centrifuged to remove the chloroplast material. The clear juice obtained was assayed to determine the amount of cytoplastic protein remaining therein. The conditions used and the results obtained are listed in the following table.

9 142934

Treatment conditions j the clear

Temperature Warm-up time in hot cooling time juice past- Appearance time, condition, second-rate cyto- 0 6.8 96 cloudy, green 60 0.6 0 10.4 88 cloudy, brown 60 0.6 10 9.1 85 clear, brown 60 0.6 20 10.6 83 clear, brown 65 0.6 0 11 , 4 80 clear, brown 70 0.6 0 10.2 71 clear, brown

During this heating step, it is important that the heat is applied in such a way that no substantial part of the juice achieves a temperature which is substantially above the specified range. Thus, if parts of the juice are overheated, there is a tendency for preferred aspects to be lost, as some of the cytoplastic protein content of the juice will precipitate with the chloroplastic protein, chlorophyll and carotenoids. Such undesirable overheating can be avoided in various ways. For example, the juice temperature can be increased by using a hot water bath or other heat source which ensures a relatively low temperature gradient. Advantageously, stirring methods can be used for the juice under heating to maintain a uniform temperature throughout the liquid. Another method consists in passing the juice through a hose immersed in a tank containing water or other heat exchange medium maintained at a temperature of 50 ° C or higher so that the juice as it passes through the hose is brought up to the desired temperature.

After the juice has been heated as described above, it is passed through a cooler 5, which may be designed as a conventional heat exchanger, in which the juice is cooled to below 40 ° C. Using the above-described treatments, the chloroplast content of the juice will be agglomerated as a fine-grained green suspension.

To separate this chloroplast material, the mixture is centrifuged (box 6) to obtain 1) the remaining partially clear juice (L-2) and 2) the chloroplastic material containing chloroplast proteins, chlorophyll, carotene, xanthophyll and other carotenoids. = pides, unidentified growth factors etc.

142934 10

This mixture is then filtered through diatomaceous earth in a filter press. Thereby a bubbly clear liquid is obtained. The chloroplast residue is returned to the diatomaceous earth filter.

After separation of the chloroplastic material in the centrifuge 6, but before transferring to the dryer 7, the centrifugate is heated by steam injection to 80 ° C for approx. 1 minute. Hereby, the centrifugate changes from a hydrophilic jelly mass to a water-giving, quark-like texture. The pulp can then be pressed to reduce the moisture content, increasing the solids content from 12% to 46%. The cake-like material can then be granulated and passed through a granulator. Then the product is fed to the dryer 7, which can be a conventional double drum or a rotary dryer. The dried product, fraction B, is a valuable material for feeding cattle. Fraction B typically contains (on a dry matter basis) the following:

Protein x 54.5%

Fat 9.3%

Fiber 1.56%

Ash 18.1% NFE ** 21.0%

Caroten 500 mg / lb.

Xanthophyl 1200 mg / lb.

x Nitrogen content x 6.25 xx Nitrogen-free extract (mostly carbohydrates), determined by difference.

Because of its high xanthophyll content, fraction B is particularly valuable as poultry feed, which produces chickens and young hens with highly pigmented (pale yellow) skins, which most consumers prefer over pale skinned chickens. Also, if chickens are kept for egg production, such xanthophyll rich rations are advantageous for obtaining eggs which have plums of deep yellow color.

Work step III. Separation of cytoplasmic protein.

(Fraction C).

The clear juice (L-2) remaining from working stage II is used as the starting material for this working step.

11 142934

The purpose of this operation is to separate the cytoplasmic proteins from the clear juice, which can be done in several ways. The cytoplasmic proteins can be precipitated in one of the following alternative ways: 1) Addition of acid to adjust a pH of approx. 3 to approx. 4.8.

2) Heating to a temperature above 50 ° C, eg 55-80 ° C.

3) Adding acid to adjust a pH of approx. 3 to approx.

4.8 plus heating to a temperature above 50 ° C, eg 55-80 ° C.

Further, one or more of the aforementioned methods of treatment may be used consecutively to ensure that the entire desired protein content is recovered. For example, you can proceed as follows: The L-2 juice is heated to 55 ° C, cooled and the precipitated protein is removed. The remaining liquid is then subjected to the same treatment one or more times, each time using a steadily increasing temperature and obtaining a series of protein isolates.

Alternatively, the above procedure can be used, but use a successively lower pH value (with or without increasing the temperature), thereby again obtaining a number of protein isolates.

Such successive treatments have the advantage that in the initial phases where the acidification and temperature conditions are mild, particularly pure and unnatural isolated proteins are obtained.

A particularly favorable treatment method comprises stepwise acidification without any use of heating. This procedure is carried out at ambient temperature (room temperature). The juice L-2 is first acidified to a pH of 4.8 and centrifuged, whereby the majority (usually 2/3) of the total amount of cytoplasmic protein is isolated in a particularly pure undaturated form. The residual liquid is then acidified to a pH of 3 and centrifuged, thereby isolating the remaining portion of the cytoplasmic protein in a pure form, however not as pure as the first fraction.

The drawing illustrates two alternative techniques for precipitating the cytoplasmic protein, one of which involves the addition of acid while the other is based on heat treatment.

12 142934

In the process carried out with the addition of acid, the clear juice (L-2) is passed from the centrifuge 6 through the conduit 8 to the mixer 9, where it is mixed with enough acid to adjust the pH to 3-4.8. Sulfuric acid, hydrochloric acid, phosphoric acid or other non-toxic acids can be used for this.

To separate the precipitated cytoplasmic protein, the acidified mixture is then centrifuged (box 10) to obtain a quark-like mass containing the cytoplasmic proteins without chlorophyll, carotenoids, lipids and bitter substances or other undesirable aroma components.

The cytoplasmic protein separated by the centrifuge 10 is then washed in the washer 11 with water (acidified to a pH of about 4-5) to remove water-soluble contaminants. After washing, the pH of the protein material is adjusted to approx. the neutral point by rinsing with a dilute solution of sodium hydroxide and passing to a drier 12, e.g., a conventional freeze dryer. The dried product, fraction C, is valuable as a supplement to cereals and other low protein feed materials. For a typical working range, fraction C (solids basis) contained the following:

Protein * 85%

Fat 0.66%

Fiber 0.20%

Ash 4.32% NFE 9.8%

Carotene nothing

Xanthophyll nothing x Nitrogen content x 6.25.

xx Nitrogen-free extract (mostly carbohydrates), determined as difference.

Using the alternative method of precipitation by heating, the clear juice (L-2) is passed through the conduit 13 to the heating apparatus 14, which may be a conventional heat exchanger or a direct steam supply heater. Herein the juice is brought up to approx. 55-80 ° C and is preferably kept at this temperature for approx. 1-5 minutes.