GB2069309A - Animal feeds and process for the production thereof - Google Patents

Abstract

A process is described for converting plant residues and wastes, such as those of labiateae from which essential oils have been extracted by steam distillation and pea and bean haulms, into an animal foodstuff. Plant material, comprising the residues or wastes is subjected to shock-drying to reduce the moisture content in minimum time to a value not above 10% by weight. The dried material is then ground so that 98 to 100% of the material has a size below 2mm., preferably 1mm, and at least 8% of the material has a size above 0.5 mm. The ground material is then sieved and a sieve fraction with a size inthe range of 0.35 to 0.75 mm., depending upon the starting material is separated. The sieve fraction with a grain size below the separated sieve fraction constitutes the desired foodstuff which may be pelletised alone or with other feed components.

Description

SPECIFICATION Animal feeds and process for the production thereof This invention relates to a process for preparing high quality animal foodstuffs or components of mixed feeds from plant sources, which have not been used or have been used only to a very limited extent for viable commercial application.

Thus several varieties of labiateae, e.g. different varieties of Mentha, especially subspecies of Mentha piperita, as well as Mentha arvensis, lavender (lavandula spica) and Melissa officinalis are cultivated on a wide scale for the essential oils which are contained in and extracted from these plates, e.g. peppermint oil, oil of lavender, etc. A mixture of the essential oils is removed from those parts of the plants which grow above soil level, by means of steam distillation. The resulting residues, the dry weight of which amounts to more than 95% of the dry weight of the plant parts used for steam distillation, are waste products without any value. Normally, the residues are removed as rubbish or burnt after having been subjected to air-drying. In some cases the residues are composted.Generally, the above procedures have a neutral costs basis, i.e. there is no profit or very little profit.

Similarly, different plants used for human nutrition, e.g. peas (Pisum sativum), beans (Phasaeolum vulgaris), broad beans (Vitia faba) and lentils (Lens culinaris) are utilized only partially for nutritional purposes. Thus quantitatively the major fractions of the vegetable matter like the haulms, comprising leaves and stems and often the shells or pods represent worthless waste products, as do the residues of the varieties of Mentha, Lavandula, etc., after the essential oils have been extracted from them by steam distillation. All these residues are unsuitable for use as animal foodstuff in spite of the considerable amount of nutritional substances, like protein and essential minerals, contained in these residues. This is not only due to their poor keeping quality but also because they can be digested in the stomach of the animals very incompletely.

It is an object of this invention to convert these residues or wastes into a product which can be assimilated very easily by practically all types of warm-blooded animals, such as chickens, (poultry), calves, sheep, pigs, cattle and goats.

Accordingly, one aspect of the present invention provides a process for producing a foodstuff for animals or an animal feed component from a material comprising plant residues and/or wastes, wherein the material is subjected to a shock-drying step during which its moisture content is reduced in minimum time to a value not above 10% by weight, and the dried material is thereafter ground so that 98 to 100% by weight of the material has a size below 2 mm. and at least 8% by weight of the material has a size above 0.5 mm. and wherein there is subsequently separated from the ground material a sieve fraction the size of which lies in the range of from 0.35 to 0.75 mm., depending on the starting material used, the sieve fraction with a grain size below this sieve fraction constituting said foodstuff or feed component.

Another aspect of the present invention provides an animal feed comprising as at least one of its ingredients a foodstuff prepared by the process just indicated.

The present process considerably reduces the raw fibre content of the residues or wastes and improves their digestibility.

The first step of the present process consists of an extremely rapid shock-drying step. Hitherto, this step has been used in a different connection, namely for the purpose of drying of digestible foodstuffs such as sugar beet flakes, fresh clover or other green feed. However, it has not been used before for the purpose of improving the ease of assimilation of a material. This drying is conveniently carried out in drum dryers, in direct contact with hot combustion gases at a temperature of from 300 to 8000 C., preferably from 350 to 5500C. During the drying, it is important to effect good thermal exchange between the gases and the material so as to prevent the material from being heated above 900 C., and so that the drying proceeds very rapidly, i.e. with a maximum dwelling time of several minutes only.The drying step is conducted so that the residual moisture content of the material is reduced below 10% preferably from 5 to 8% by weight.

In the next step of the present process, the dried material is subjected to grinding which should be neither excessively fine nor too coarse. The degree of fineness is to be such that 98 to 100% of the material has a size below 2 mm., preferably below 1 mm. However, not less than 8% and preferably more than 12% e.g. 15% and above should have a grain size above 0.5 mm. If the first step, i.e. shockdrying, and the subsequent grinding are carried out correctly then the raw fibre is ground to a much smaller extent than all the other plant components. This permits the finely ground material to be fractionated in the third step of the process by sieving.The selection of suitable sieves enables an oversize fraction with the most coarse grains and containing the main part of the raw fibre content together with minor amounts of other plant components to be obtained. The finer grain fraction or fractions contain all other plant components of the starting material in practically unaltered qualities.

Consequently, the latter fraction or fractions contain significantly reduced quantities of raw fibre.

The optimum sieve sizes employed depend upon the type of starting material used as well as the degree to which it is desired that the raw fibre content is reduced or to which a reduction of nutritional substances can be allowed, and in any case lie in the range 0.35 to 0.75 mm., and especially 0.5 to 0.6 mm.

As a result of this lowering of the raw fibre content, while preserving a considerably fraction of all nutrients contained in the starting material, plant wastes, which are unsuitable or only suitable to a limited extent for animal nutrition, can be converted to valuable foodstuffs or foodstuff components.

In order to avoid losses and to reduce troubles due to the fact that the finely ground material is in the form of a dust, it is preferred to pelletise the ground product in known manner before use, preferably immediately after sieving. The product may be pelletised by itself to form an animal feed or may be pellitised together with a mixture of other components to form a mixed feed.

The present process is particularly valuable for processing plant wastes which have a high nitrogen content. Thus the process is valuable for treating not only the haulms (stems and leaves) and shells or pods of legumes like peas, beans and lentils but also for treating the residue of Mentha plants after removal of essential oils therefrom, as these residues possess a high nitrogen content according to Kjeldahl, viz a protein content of 12 to 14%, i.e. of the same order as that of legumes.

The large quantities of vine leaves (Vitis vinifera) which become available in early summer due to pruning are also suitable as a starting material for the present process.

The invention will now be illustrated by the following Examples in which percentages are by weight unless otherwise indicated: EXAMPLE 1 Production of Foodstuff from Mentha: 4500 kg. of Mentha piperita L. (Hybrid Mitcham) were subjected to a conventional method of steam distillation for the removal of essential oils therefrom, the plant components consisting of those parts of the plants growing above soil level with a dry matter content of 25 to 28% and a cellulose content according to Sharrer of 35% relative to dry matter. The residues from the steam distillation were air-dried to a water content of 45 to 55% and then dried further up to a residual humidity of 5%, using a cylindrical drum drier of 11 m. length and 2.5 m. diameter, rotating at 4 r.p.m.Drying was carried out with hot combustion gases at a temperature of 3500C. to 6000C. at drum inlet and 110 to 1 300C., at drum outlet, depending on the water content of the plant components.

The dried Mentha residues (1220 kg. x 27% of the initial plant components) obtained by the above procedure, were ground to a size of 0.06 to 1.0 mm. in a second process step.

The sieve analysis of this powder was carried out according to DIN 10765, with the exception that instead of a 0.04 mm. sieve, the procedure was started with a 0.063 mm. sieve. After each sieving cycle, the sieve residue was added to the next larger sieve. The non-transferably residue from each sieve (0.00 to 0.03 g.) was numerically added to the quantity added to the next higher sieve.

Grain size Sieve Analysis (%) mm. 1 st analysis 2nd analysis mean value below 0.063 7.60 7.60 7.6 0.063-0.100 6.40 6.25 6.3 0.100-0.250 27.45 28.35 27.9 0.250-0.500 42.85 42.6 42.8 0.500--1.000 15.3 15.15 15.2 above 1.0 0.4 0.05 0.2 100.0 In a third process step, the powder was subjected to a sieve fractionation with a 0.5 mm. sieve.

The oversize fraction above 0.5 mm. was rejected. The fraction below 0.5 mm. amounted to 1080 kg., corresponding to 24% of the plant components used or 88.5% of the dried Mentha residues. The anal ytical data of this fraction are as follows: Water content 5.0 /0 Crude protein (N2 x 6.25) 13.5% Cellulose acc. to Sharrer 28.0% Fat 3.0% Ash 6.9% Sodium 0.15% Potassium 1.87% Calcium 1.34% Magnesium 0.80% Iron 1,341 mg./kg.

Manganese 1 06mg./kg.

Copper 26 mg./kg.

Zinc 66 mg./kg.

Cobalt 2.5 mg/kg Essential amino acids (% rel. to crude protein) Isoleucine 4.5% Methionine 5.1% Leucine 7.8% Lysine 9.5% Arginine 4.1% Tyrosine 2.5% Valine 8.0% Feeding and Growing Trials: 200 broilers (Hybrid Hubbard) 1 day old, were divided into two groups A and B, consisting of 100 broilers each (50% male, 50% female). The group A were fed with the following mixed feed which contained the Mentha Meal prepared as described above: Soyabean meal 22% Mentha meal 6% Cereal meal 42% Wheat meal 20% Concentrate "Nutrikem" Type 1603 10% The group B were fed for control purposes with a mixed feed having an identical composition to that given above, with the exception that instead of 6% Mentha meal and 42% of Cereal meal, it contained 5% Alfalfa meal and 43% Cereal Meal.

The Feed Conversion and increase of body weight are compiled in the following Table: Duration of Growth

28 days T 54 days 72 days Weight Weight Weight increase Increase Increase FCl+) FOCl+) h FCI+) Group A 1969 1.87 5093 2.23 8531 2.09 Group B 1758 t.95 4583 2.32 7638 2.14 (control) Feed use (kg.) +) FCI:Feed Conversion Index Weight increase (kg.) EXAMPLE 2 Production of Foodstuff from Pea Wastes: 4500 kg. of pea waste (leaves, stems, shells), having a cellulose content according to Sharrer of 31% relative to dry matter and a water content of 60 to 70%, which are produced as a waste byproduct in the course of industrial preservation of peas by canning or deep-freezing, were dried to a residual moisture content of 7% in a drum drier by the method described in Example 1. Subsequently, the dried wastes were ground and finally fractionated.

The sieve analysis, carried out in the same manner as in Example 1, gave the following result: Grain size (mm.) Sieve analysis (%) below 0.063 14.3 0.063-0.100 14.95 0.100-0.250 34.6 0.250-0.500 24.25 0.500--1.000 10.65 above 1.0 1.25 100.00 The resulting dried pea waste meal was subjected to a sieve fractionation as described in Example 1, with a sieve of 0.5 mm., and the fraction below 0.5 mm., was found to amount to 1230 kg. = 27.3% relative to the moist raw material.The analytical data of this fraction were as follows: Water content 7.0% Crude protein 16.5% Cellulose acc. to Sharrer 24.0% Ash 9.4% Fat 2.5% Sodium 0.10 /6 Potassium 1.23% Calcium 1.86% Magnesium 0.32% iron 908 mg./kg.

Manganese 36 mg./kg.

Copper 1 5 mg./kg.

Zinc 45 mg./kg.

Cobalt 0.012 mg./kg.

Essential amino acids (% rel. to crude protein) Isoleucine 9.3% Methionine 1.6% Leucine 7.6% Lysine 11.3% Arginine 4.3% Tyrosine 1.4% Valine 7.5% a) Feeding and Growing trials with broilers: The above pea waste meal was used to make a mixed feed A of the following composition: Soyabean meal 22% Pea waste meal 5% Cereal meal 43% Wheat meal 20% Concentrate "Nutrikem" Type 1603 10% A mixed feed B was used for control purposes and differed from the mixed feed A in that the pea waste meal was replaced by Alfalfa meal.

Feeding trials were carried out in the manner described in Example 1, with 200 broilers (Hybrid Hubbard), 1 day old, divided into two groups of 100 broilers each and bred for 72 days. The average body weight increased amounted to 8243% in the case of Group A and 7680% in the case of Group B (control) respectively.

The Feed Conversion Index was 1:2.11 in the case of Group A and 1:2.14 in case of Group B respectively.

b) Feeding and growing with pigs: A mixed feed C in pelletized form was produced with the above described pea waste meal with the following components: Cereal meal 38% Pea waste meal 38% Fish meal 12% Soya scrap 11% Mineral supplement 1% A mixed feed D, used for control purposes, differed from mixed feed C only by the fact that the pea waste meal was replaced by Alfalfa meal.

Two groups each of 10 pigs which were 14 days old and had an average body weight of 32 kg.

were reared, one group being fed with the mixed feed C and the other with the control feed D. The pigs were reared to the age of 24 weeks. The average increase of weight amounted to 106.25% in the case of Group C and 101.56% in the case of Group D (control). The Feeding Conversion Index in the 24th week was 1:6.24 for group C and 1:6.29 for Group D (control).

By following the process steps of shock-drying, grinding and sieving described in the above Examples, similar meals were produced from the leaves or green wastes of field beans, beets, vines and carrots, sieve sizes of 0.6 mm. being used for beans and 0.8 mm. for vines, beets, and carrots. Similar good results were obtained when these were fed to broiler chickens, pigs and goats, as part of the feed.

Claims (14)

1. A process for producing a foodstuff for animals or an animal feed component from a material comprising plant residues and/or wastes, wherein the material is subjected to a shock-drying step during which its moisture content is reduced in minimum time to a value not above 10% by weight, and the dried material is thereafter ground so that 98 to 100% by weight of the material has a size below 2 mm. and at least 8% by weight of the material has a size above 0.5 mm, and wherein there is subsequently separated from the ground material a sieve fraction the size of which lies in the range of from 0.35 to 0.75 mm., depending on the starting material used, the sieve fraction with a grain size below this sieve fraction constituting said foodstuff or feed component.

2. A process as claimed in claim 1, wherein the shock-drying step is carried out so that the moisture content of the dried material is 5 to 8% by weight.

3. A process as claimed in claim 1 or 2, wherein the oversize fraction above the sieve fraction is rejected.

4. A process as claimed in any one of claims 1 to 3, wherein the grinding is carried out in such a manner that more than 12% by weight of the material has a grain size of 0.5 mm.

5. A process as claimed in any one of claims 1 to 4, wherein the grinding is carried out in such a manner that 1 5% by weight of the material has a grain size of 0.5 mm.

6. A process as claimed in any one of claims 1 to 5, wherein the sieve size is about 0.5 mm.

7. A process as claimed in any one of claims 1 to 6, wherein the recovered fraction below 0.35 to 0.75 mm., is pelletised for use as a foodstuff or feed component.

8. A process as claimed in any one of claims 1 to 6, wherein the recovered fraction below 0.35 to 0.75 mm. is pelletised with other feed components to form a mixed feed.

9. A process as claimed in any one of claims 1 to 8, wherein the grinding is carried out so that 98 to 100% by weight of the material has a size below 1 mm.

1 0. A process as claimed in any one of claims 1 to 9, wherein the starting material comprises those plant components which grow above soil level of the genus labiateae, and from which essential oils have been removed.

11. A process claimed in claim 10, wherein the plant components are obtained from Lavandula or a variety of Mentha.

12. A process as claimed in any one of claims 1 to 9, wherein the starting material comprises those parts of plants of the genus Leguminoseae, not suitable for human consumption.

13. A process as claimed in claim 12, wherein said parts comprise the stems, leaves and/or shells or pods of peas. beans and/or lentils.

14. A process for producing a feestuff for animals or an animal feed component substantially as hereinbefore described in either of the foregoing Examples.

1 5. A feedstuff for animals or an animal feed component produced by the process claimed in any preceding claim.