FI87881B - Method for recovering and treating press liquid from ensilage, novel fodder composition obtained by this method, and use of the syrup obtained by this method - Google Patents

Description

1 87881

The invention relates to a method for recovering and treating a silage compost liquid, to a novel feed composition obtained by the process and to the use of the syrup obtained by the process.

Silage press is a serious environmental problem in Finland and many other 10 countries. In connection with the production of fodder and silage prepared using the VAT method, a large amount of pressed liquid is generated, and in Finland, for example, thousands of tonnes of pressed liquid are produced every year. Until now, the pressed liquid has hardly been utilized, but most of the pressed liquid is lowered as such to the ground or driven into the fields. The eutrophication and groundwater pollution effect of these measures is very significant.

However, silage press liquid contains valuable components such as sugars, proteins, peptides, amino acids and other soluble ingredients in fresh grass mass. For this reason, attempts have been made to feed silage press liquid to cattle. However, the use of all the pressed liquid as such as livestock feed and at the same time to avoid the aforementioned environmental problems is hampered by the large amount of pressed liquid generated and the unused amount. the susceptibility of the pressurized liquid to spoil very quickly. For example, in the production of silage by the Alv method. . the liquid is formed in a few weeks and is present in an amount of _30 about 5-10% by weight based on the feed weight. In addition, silage is produced in the summer, when there is usually no need for fodder, as products are then available for livestock; retta food.

Surprisingly, a method has now been invented for recovering and treating silage pulp to obtain a concentrated syrup called grass molasses, which can be used as animal feed. In addition, said syrup can be used, for example, as a sweetener in the food industry, as a raw material in the production of ethanol and as a growth medium for various microbes.

The method according to the invention for recovering and treating silage compression fluid, wherein the compression fluid from the feed silo or hopper is introduced into a tank during silage production, is characterized in that the compression fluid is discharged or pumped into a tank to which sodium benzoate and / or potassium sorbate have been added. the total amount in the pressurized liquid in the tank is at least 15 0.1% by weight, and the fact that the pressurized liquid containing sodium benzoate and / or potassium sorbate is evaporated to a concentrated syrup with a dry matter content of 40-85% on a Brix scale by vacuum evaporators with a boiling point of 70 to 80 ° C, 20 when the pH of the pressed liquid is 2 to 7, whereby before evaporating the pressed liquid it is i) pasteurized if necessary and ii) desalted if desired. In the production of traditional printed feed, moist plant material is preserved as animal feed by natural lactic acid fermentation. In this case, from several years, the pressed liquid, the sugars contained in it, have at least partially fermented into milk from the silo or auma. . poksi. The press liquid thus obtained resembles a dilute lactate solution and can be treated by the process of the invention.

However, the method according to the invention is particularly well suited for the treatment of silage compaction liquid prepared by the AlV method. The VAT method is based on the addition of acid to fresh grass. In this method, a decrease in the pH of 3> 37 881 silage to close to four causes plasmolysis in the feed, as a result of which the press liquid is released from the silage much faster than, for example, in the production of conventional weight feed. Due to the low pH, the sugars in the pu-5 concentrate are not consumed in fermentations and the protein is not broken down.

In the process, in connection with the production of silage, the pressed liquid coming from the feed silo or hopper is led by draining or pumping to a tank to which sodium benzoate or potassium sorbate or a mixture thereof has been added as a preservative. Said substances have not previously been used for the preservation of press liquid. The amount of sodium benzoate and / or potassium sorbate in the tank must be at least 0.1% by weight, based on the pressurized liquid in the tank.

In order to keep a sufficient amount of preservative in the tank at all times, a concentrated preservative charge is fed into the empty tank before the pressurized liquid is introduced into the tank. When the pressurized liquid is then introduced into the tank, the preservative charge therein is diluted as the tank is filled and the preservative content of the liquid in the tank decreases. At the same time, the preservation of longer batches of pressurized liquid in the tank is also ensured, because there is always an excess of preservative in an empty or incomplete tank. As the amount of sodium benzoate and / or: 25 potassium sorbate, even in a full tank, must be at least 0,1% by weight of the pressurized liquid in the tank. calculated, for example, at least 1 kg of preservative must be fed into an empty 1000 l container. In this way, the country. . The silage effluent from the manufacture of silage may be preserved for at least some weeks.

In contrast, without preservatives or in the literature, good preservation results are not obtained with the recommended formic acid and formalin for preserving feed. This is also apparent from Example 1 below, in which 4 · i 7 3 31 describes the preservation of silage press liquid with various preservatives.

The success of preserving a pressed liquid is best illustrated by its lactic acid content. When preservation fails, hii-5s can grow in the pressurized liquid and the lactic acid content is the first to indicate this fermentation.

Pressed liquid stored on farms is transported to the treatment plant in a tank truck or collection tank. Since the production of silage on different farms usually takes place at the same time and as a large part of the silage is generated in the early stages of silage production, at least most of the silage stored on farms can be collected centrally by a tank truck circulating on farms.

15 A plant for the treatment of stored pressurized liquid may be, for example, a dairy property that has been decommissioned.

In the recovery and handling of the pressed liquid, it is important that it can be heat treated to improve the microbiological quality. If the proteins and other ingredients contained in the pressed liquid precipitate during the heat treatment, the heat exchanger may become clogged, making further processing of the product difficult.

When heating batches of pressurized liquid having different pH values to 75 ° C and 100 ° C, it was found that the pressed liquid can be heated without precipitates to 75 ° C when the pH of the pressed liquid is 2 to 7 and to 100 ° C when the pH of the pressed liquid is 2 to 6.

If necessary, the pressurized liquid is pasteurized. This can-. . can be done, for example, with a milk paste by placing the compressed liquid at a temperature of 70 to 90 ° C for a residence time of 15 s to 15 min.

The salt content of the pressed liquid is quite high, about 20% by weight of the total dry matter, measured as ash. In particular, the pressurized liquid contains a lot of potassium (about 10 "• '35% by weight of dry matter). The high potassium content can cause problems in animal nutrition. If it is desired to make a syrup containing less salts from the pressurized liquid, it can be derived e.g. electrodialysis or ion exchange equipment for desalination of whey.

5 The effect of desalination on the chemical composition of the pressed liquid is described in Example 2 below.

Syrup from a pressed liquid can be used for animal feed, but a particularly suitable and tasty syrup for feeding animals is obtained when the salt content of the pressed liquid is reduced by 50%.

If desired, other components other than sugars can be removed from the pressed liquid. For example, pure sugar feed can be prepared from the pressed liquid by chromatographic separation.

15 The preservative-containing pressurized liquid is evaporated into a concentrated syrup with a dry matter content of 40-85% on a Brix scale.

For evaporation, for example, vacuum evaporators commonly used in dairies for concentrating milk and whey can be used, in which the boiling temperature is generally 50 to 80 ° C. Critical issues for concentration are solution viscosity and precipitates. Surprisingly, the pressed liquid can be easily evaporated on a vacuum evaporator at a temperature of 70 to 80: · .: ° C to a dry matter content of up to 80%, measured on the Brix scale of the refractometer, when the pH of the pressed liquid is 2 to 7. No precipitation or fouling of the vacuum evaporator. .

80% compressed liquid concentrate, i.e. grass. . The glass is easily pumped at 20 ° C. In addition, it has been found that already 50% (° Brix) grass molasses remains at room temperature for a month.

For the further use of grass molasses, the most suitable dry -: * · material range is 50 - 80%.

The invention also relates to a novel feed composition obtained by the process according to the invention described above. This new feed composition is thus a concentrated syrup obtained by evaporation of silage press liquid with a dry matter content of 40-85%.

For some of the components important for feed use, the composition of grass molasses corresponds to the composition of mixed molasses, which is commonly used in compound feed and is a by-product of the sugar industry. If the salt content of the pressed liquid is reduced by 50%, the composition of the 50% demineralized grass molasses obtained therefrom is better than the composition of the mixed molasses for feeding the livestock.

The following table shows the compositions of ordinary grass molasses and 50% demineralized grass molasses, as well as the composition of known mixed molasses for the components important for animal nutrition.

15 Table 1

Composition of ordinary and 50% demineralised grass molasses compared to mixed molasses for animal feed

Crude Nitrogen-free Ash 2 0 protein extractives% by weight% by weight ·; ·· Ordinary grass molasses 10 70 20 50% demin.

: 25 grass molasses 10 80 10

Mixed molasses 9 74 17

The feed composition according to the invention contains dry. ; 10% by weight of crude protein, 70 to 80% by weight of nitrogen-free extracts and 10 to 20% by weight of ash, λ The preferred feed composition according to the invention contains 10% by weight of crude protein, 80% by weight of nitrogen-free extracts and 10% by weight of ash.

Il 7 87881

In addition to feeding the animals, the grass molasses obtained by the process according to the invention can be used, for example, as a sweetener in the food industry, as a raw material in the production of ethanol and as a growing medium for various microbes.

The invention therefore further relates to the use of the concentrated syrup obtained by the method according to the invention as a microbial growth medium.

As previously stated, the present invention avoids the environmental problems caused by the silage compression liquid and, in addition, makes the valuable ingredients contained in the compression liquid easy to utilize.

The significant share of pressed liquid in agricultural 15, eutrophication and groundwater discharges is illustrated, for example, by the following table in MK Woolford's The Silage Fermentation, Marcel Dekker Inc, New York and Basel, 1984, page 173, which shows the consumption of some agricultural emissions. amounts of biological oxygen:

Table 2

The biological oxygen demand of some agricultural emissions. *. lute Emission Biological oxygen demand; (mg 02 l'1) Silage press liquid 90,000

Piglets 35,000

Cow urine 19,000

Navettaliete 5,000

Household waste 500

The following examples describe in more detail the preservation of silage pressed liquid with various preservatives and its desalination.

e 87881

Example 1 Silage was normally prepared from grass using AIV II solution (6 1 / t grass mass as preservative; AIV II solution contains 80% by weight formic acid and 2% 5 phosphoric acid). The squeezing liquid was collected as it began to come off. The pressed liquid was immediately frozen and used later in the experiments shown in this and other examples. The storage experiment compared the shelf life of the compressed liquid without preservative, with preservatives known from the literature, formic acid and formalin, as well as with sodium benzoate and potassium sorbate. Table 3 shows the results of the monthly storage test (storage at room temperature for one month).

Table 0 3 Effect of different preservatives on the storage temperature of the pressed liquid at room temperature in the monthly storage test Storage method pH lactic acid-sugar protein content (%) concentration (%) decomposition

Fresh squeezed 4.2 1.2 5.6 Ten without preservative (before storage) 0.5% formic acid 4.4 0.2 2.1 0.1% formalin 4.1 0.4 4.5 0.1 % N-benzoate 4.1 1.0 6.0 0.1% K-sorbate 4.3 1.0 4.4

Pressed liquid 4.4 0.3 4.1 + without preservative (after 1 month of storage) 9 87881

It can be seen from the table that the formic acid and formalin recommended for mucus preservative and pulp in the literature do not achieve good preservation results, i.e. a good lactic acid content close to 1.2% of fresh pulp and a good sugar content close to fresh pulp. 6%. In contrast, the In some cases, lactic acid and sugar levels decrease and without preservative, protein degradation is also ha-10 claimed. Sodium benzoate and potassium sorbate, on the other hand, proved to be good preservatives even at a concentration of 0.1%.

Example 2

The salt content of the press liquid is about 20% of the total-15 female dry matter, measured as ash, and in particular the press liquid contains a lot of potassium (about 10% of the total dry matter). A laboratory-scale electrodialysis device was used for desalination of the pressed liquid, which is similar in principle to the industrial whey desalination equipment. The degree of desalination was monitored by measuring the conductivity of the solution. Desalting was very successful and no fouling and clogging of the films was observed. When the desalination rate was 50% according to conductivity, more than 60% of the potassium had already been removed. Table 3 shows the changes in the chemical composition of the pressed liquid during desalination. Ko. the table also shows that the losses of soluble protein and non-protein nitrogen are surprisingly small. For this reason, the method used is well suited for lowering the potassium content of the pressed liquid.

10 87881

Table 4

Effect of desalination on the chemical composition of the pressed liquid 5 Desalination rate (%) 0 50 70 90

Ash (%) 2.2 1.0 0.7 0.2

Calcium (mg / kg) 1300 850 520 120

Magnesium (") 550 260 260 84

Potassium (") 11500 4100 2400 165 10 Sodium (") 420 110 86 21

Phosphorus (") 810 620 520 160

Chlorides (") 3300 290 56 13

Soluble protein (%) 1.1 0.95 0.94 0.83

Non-protein N (mg / g) 1.6 1.4 1.3 1.2

Example 3 15

A batch of pasteurized pasteurized milk powder (80 ° C, 1 min) was evaporated on a vacuum evaporator commonly used in dairies at a temperature of 70-80 ° C. The dry matter content was measured on a Brix scale of the refractometer and evaporation was stopped when the dry matter content was found to be 50%.

The 50% ordinary grass molasses obtained contains 10% by weight of crude protein, 70% by weight of nitrogen-free extracts and 20% by weight of ash, calculated on the dry matter.

. · · 25

Example 4

A batch of demineralized press liquid according to Example 2 was evaporated on a vacuum evaporator commonly used in dairies at a temperature of 70-80 ° C.

. ·. : The dry matter content was measured on a refractometer in ° Brix and evaporation was stopped when the dry matter content was found to be 80%.

The 80% 50% demineralized grass molasses obtained contains, based on the dry matter, 10% by weight of crude protein, 80% by weight of nitrogen-free extracts and 10% by weight of ash.

Claims (8)

11 87881 A method for recovering and treating silage compression fluid, wherein the compression fluid from the feed silo or hopper is introduced into a tank during silage production, characterized in that the compression fluid is discharged or pumped into a tank to which sodium benzoate and / or potassium sorbate have been added in an amount such that / its total content in the pressed liquid in the container is at least 0.1% by weight, and the fact that the pressed liquid containing sodium benzoate and / or potassium sorbate is evaporated to a concentrated syrup with a dry matter content of 40-85% on a Brix scale, with evaporators having a boiling point of 70 to 80 ° C when the pH of the pressed liquid is 2 to 7, whereby before evaporating the pressed liquid it is i) pasteurized if necessary and ii) desalted if desired. Process according to Claim 1, characterized in that the pressed liquid is evaporated into a concentrated syrup having a dry matter content of 50 to 80% on a Brix scale. Process according to Claim 1 or 2, characterized in that, before evaporating the pressed liquid, its salinity is reduced by 50%, preferably by means of electrodialysis or ion-exchange equipment used for desalination of whey. Feed composition, characterized in that it is a concentrated syrup having a dry matter content of 40 to 85% on a Brix scale and prepared from a pressed liquid by a method according to claim 1, 2 or 3. Feed composition according to Claim 4, characterized in that it contains, based on dry matter, 10% by weight of crude protein, 70 to 80% by weight of nitrogen-free extractives and 10 to 20% by weight of ash. 12 87881 Feed composition according to Claim 5, characterized in that it contains, on a dry matter basis, 10% by weight of crude protein, 70% by weight of nitrogen-free extractives and 20% by weight of ash. Feed composition according to Claim 5, characterized in that it contains, based on dry matter, 10% by weight of crude protein, 80% by weight of nitrogen-free extractives and 10% by weight of ash. Use of a concentrated syrup obtained by the method 10 according to any one of claims 1 to 3 as a microbial growth medium. i3 87 881