DK149544B - PROCEDURE FOR THE MANUFACTURING OF A LIQUID FOOD - Google Patents

Description

149544

The present invention relates to a process for preparing a ruminant feed in which a lignocellulosic product is treated with an aqueous solution of sodium hydroxide at a temperature of more than 60 ° C.

05 It has been known for more than 50 years that the digestibility of straw can be increased by alkali treatment. This method, which has been used in practice in Germany and Norway, and which is known as Beckmann's method (treatment with solution, leaching of excess alkali with water), has now been displaced for example by the newer methods which is stated by the Danish Rex,

Stigsen and Kristensen.

A method of the above-mentioned type for the preparation of feed intended for ruminants is known from French Patent Specification No. 2126365, which discloses a process for preparing animal feed from a mixture containing lignocellulose and an aqueous solution of alkali. This known process is characterized in that said mixture, having a solids content of at least 30%, is non-cananically mixed at a temperature of at least 60 ° C. Thereby, animal feed is obtained whose organic matter has a relatively high digestibility rate.

The above-mentioned known methods have certain disadvantages. In particular, the non-digestible constituents of the lignocellulosic products such as lignin, upon which pure alkali hydrolysis has no effect under the conditions involved, cause difficulties. As these substances are fixed in the cell walls, they significantly reduce the effect of alkali hydrolysis.

The present invention has for its object to alleviate the disadvantages mentioned above. Furthermore, it is an object of the invention to provide a new method of producing from a straw a ruminant feed, the digestibility and feed value of which is considerably higher than previously produced straw fodder. The method according to the invention is characterized by the characterizing part of claim V.

The invention is based on research work, having found, on the basis of animal studies and experiments carried out in connection therewith, that the addition of oxidizing materials and oxidation catalysts by the semi-dry alkali hydrolysis process 2 149544 reduces the lignin content of the products obtained and increases their utility. In experiments, it has been found that in the rumen rumen, more volatile fatty acids (carboxylic acids having 1 to 6 carbon atoms) are released by using feed prepared by the oxidative semi-dry hydrolysis according to the invention than by using feed produced exclusively by alkali hydrolysis or by semi-dry hydrolysis. Feeds prepared by the process of the invention can be added to feed concentrate, for example in an amount up to 45%. The best digestibility is achieved in the region of about 35%, and at this level wheat straw treated by the process of the invention provides ruminants with 90% of the amount of digestible energy that grain provides.

In addition, studies have shown that addition of urea, for example 0.5 to 5%, conveniently 15 to 3%, to raw material containing lignocellulose, during such semi-dry alkaline oxidizing hydrolysis, improves the digestibility of the products. In addition, the addition of urea improves the feed value of the feed in a known manner.

The invention rests on alkaline hydrolysis of a material containing lignocellulose which according to the invention is carried out in the presence of an oxidizing catalyst and semi-dry, i.e. at a moisture content of 10 to 20%. The process includes a strong mechanical tearing of the mixture which is formed by which the raw material's cells are disrupted and the alkali is allowed to efficiently hydrolyze on the lignocellulose. In particular, surprisingly in the process is the fact that the oxidation catalyst works effectively even in the semi-arid conditions.

The lignocellulosic material brought to use 30. in the process, for example, may be straw, hay or the like. The raw material is suitably used in the dry state, i.e. with a usual moisture content of 8 to 12%, usually approx.

10%. Prior to processing, the raw material is comminuted by cutting to chop with a length of 0.1 to 5 cm and possibly grinding to flour. The 35 comminuted raw material is sieved as required.

The oxidation catalyst used in the process can be any physiologically tolerated catalyst known per se, for example copper, iron, manganese, cobalt, nitrate, chromium, nickel, , vanadium and / or per-manganate catalyst such as copper sulfate, potassium permanganate, potassium bi chromate, potassium nitrate and / or sodium sulfate; in addition, nickel-05 or vanadium oxide can be added to the reaction mixture. The amount of catalyst added is 0.5 to 5%, preferably 1 to 3%, calculated relative to the amount of straw.

The amount of sodium hydroxide used in the process is 1 to 10%, preferably 2 to 8%, advantageously about 10%. 5% calculated in relation to the amount of straw. The sodium hydroxide is conveniently added to the feedstock at a concentration higher than 30%, advantageously higher than 50%, such as in the dry state.

To the lignocellulose-containing feedstock is added with the oxidation catalyst and sodium hydroxide and / or in addition to these 10 to 20% moisture, whereby the amount of lignocellulosic feedstock and of the dry matter throughout the mixture is 60 to 90%; the amount of water in the mixture is 10 to 30%.

The reaction between the lignocellulosic feedstock, the oxidation catalyst and the sodium hydroxide, i.e. the hydrolysis, for example, carried out in a separate container after mixing the raw materials, usually lasts 2 to 120 minutes, preferably 10 to 90 minutes, or 20 to 60 minutes, advantageously approx. 20 to 30 minutes. The reaction temperature is conveniently 30 to 100 ° C or 40 to 80 ° C.

The mechanical treatment of the raw materials and additives, the grinding, is conveniently carried out with a conventional granulation press commonly used in the manufacture of fodder, the mixture being introduced into a cylinder cavity in whose walls bores are formed. In addition, grinding and granulation of the mixture 30 is carried out by means of so-called coils, i.e. parallel to the cylinder cavity, generally cylindrical granulating means, by being pressed and twisted vigorously toward the inner surface of the cylinder cavity. The treatment is carried out at a temperature of 60 to 120 ° C, suitably 80 to 100 ° C. When tearing the mixture in question in the granulator, the instantaneous pressure acting on the raw material varies from zero to several tens, up to hundreds of ato. In this way, the cellular tissue of the raw material breaks down extremely efficiently and the hydrolysis can take place quickly. The treatment time can range from some half-dozen seconds up to some half-dozen minutes, for example within the range of 0.5 to 10 minutes, preferably 1 to 5 minutes.

The invention is described in more detail below by means of examples.

Example 1 880 parts ground or chopped straw (chop length 0.1 to 5, 10 cm) are mixed in a flour mixer with 20 parts oxidizing mixture consisting of 1 to 5 parts CuSO 4 * 5H 2 O, 1 to 5 parts KMnO 4, 5 to 10 parts KN03 and 5 to 10 parts of anhydrous Na 2 SO 4. In the same mixer, 100 parts of NaOH solution (30 to 70% by weight) is added by a suitable liquid addition method. When the mixture is homogeneous 15 (2 to 20 minutes depending on the mixer type), it is transferred to a seminal regular granulation press for feed preparation, which may be supplied with steam. The product will then stay for a few minutes at a temperature of 80 to 100 ° C. Depending on the later application and after finishing the straw chopped in the beginning, the final product can be granulated into grains with a diameter of 5 to 20 mm. For example, after the grains are cooled in a conventional device, they contain, for example, 10 to 16% moisture. In order to use the grains in compound feed, they can be further ground in a conventional hammer mill.

25 The final products can be added to compound feed for ruminants in an amount up to 45% according to formula and purpose. As a starting point, a mixture of 800 to 850 parts of straw and 30 to 70 parts of urea can also be used.

Instead of cereal straw and to replace it, other products containing lignocellulose such as rice husks, fruit waste (grapes, tomatoes, olives), coffee meat, cabbage, palm, sawdust, hay of poor quality, etc. is used.

The oxidation catalyst may be of any known type, for example a copper, iron, manganese or cobalt salt. Prior to processing, an oxidizing agent such as nitrate or permanganate may also be added. Potassium permanganate acts at once as an oxidizing agent and as an oxidation catalyst.

5 149544

Example 2 1) By comparison of ordinary straw, straw which has undergone the oxidizing hydrolysis and medium quality grains with respect to that of animals and obtains useful energy value 05, the following values are obtained: Usual straw 1300 calories

Processed straw 2600 calories

Medium-quality cereals 3000 calories 10 2) Transformation in the rumen. The release of volatile acids, the indicator of degradability of the cellulose, gives the following values 1, 2, 4 and 8 hours after ingestion: 15 1 h 2 h 4 h 8 h Usual straw 100 100 100 100

Hydrolyzed straw, no oxidation 170 117 106 102

Hydrolyzed Straw, Oxidized 213 143 134 127 20 3) In the case of cattle growth, the daily weight gain achieved was between 300 and 370 kg live weight, and the feed efficiency (feed / weight gain) during this period was as follows: 25

Daily weight gain increase degree_ Usual straw 1045 6.80 (35% of feed) 30 Oxidized, hydrolyzed straw 1293 5.37 (35% of portion)

Example 3

The procedure of Example 1 was carried out using the following catalysts: a) 1 to 5 parts CuSO 4-5H 2 O 1 to 5 - KMnO 4 5 to 10 - KNO 3 5 to 10 - Na 2 SO 4 05 b) 1 to 3 parts CuSO 4 1 to 3 - KMnO4 1 to 3 - K2Cr207 0.5 to 1 - V-oxides (V205) • JO1 to 2 - Ni2O3 (mixture of mono- and dioxide) 5 to 10 - KN03 1 to 2 - Co2 O3 (mixture of mono- and dioxide) 5 to 10 - Na2 SO4 Ί5 c) 0.5 to 2 parts CuSO4 1 to 5 - KMn04 1 to 3 K2Cr207 0.5 to 1 - V20 2 to 3 - Ni203 20 1 to 2 Co203 5 to 10 - kno3 5 to 10 - Na 2 SO 4

The mixture had a moisture content of 10 to 12%. The reaction phase was carried out at a temperature above 60 ° C for 40 minutes.

The grains coming out of the granulator had a temperature of approx. 85 ° C. The pH of the reaction mixture was above 7. The digestibility of the products corresponded to the digestibility of the oxidized products in Example 2.

30

Example 4

Wheat straw, ground in a hammer mill, was treated as follows: 1) 4% sodium hydroxide, absolute moisture content 10 to 12%, the product was granulated immediately after mixing, no catalyst, 2) as under item 1) but in use of catalyst and reaction time, 3) as under point 2) but moisture content 27%.

05 The improvement in digestibility of dry matter and organic matter (in%) was determined for the products produced and 0) for untreated straw according to a modified Tilley-Terry method. The results are listed in Table 1.

Ί0 TABLE 1

Digestibility increase_

Organic substances

Experiments Digestibility Digestibility Digestibility_ 15 o - 1 69.8% 73.1% 2 111.5% 132.7% 3 38.8% 46.8%