WO1998053703A1

WO1998053703A1 - Method for improving the resistance of proteins in seeds to degradation and the thus obtained product

Info

Publication number: WO1998053703A1
Application number: PCT/NL1998/000314
Authority: WO
Inventors: Jakob Van Bruggen
Original assignee: Schouten Products B.V.
Priority date: 1997-05-29
Filing date: 1998-05-29
Publication date: 1998-12-03
Also published as: NL1006163C2; AU7791698A; AU731500B2

Abstract

The invention relates to a method of improving the resistance to degradation of proteins in seeds for use in animal feeds, in particular for ruminants such as cows, comprising the steps of providing seeds that are reduced in size, so-called seed parts; subjecting the seed parts to a heat treatment; flaking the treated seed parts; optionally cooling and/or drying the flakes; and treating the flakes with formaldehyde.

Description

METHOD FOR IMPROVING-THE RESISTANCE OF PROTEINS IN SEEDS TO DEGRADATION AND THE THUS OBTAINED PRODUCT

The present invention relates to a method of improving the resistance to degradation of proteins in seeds used in animal feeds, in particular for ruminants such as cows. The invention further relates to the thus obtained product and the use thereof in animal feeds.

Proteins form an important part of the nutrition of humans and animals. They are inter alia important in providing essential amino acids which cannot be produced by the human or animal body itself, and in provid- ing nitrogen (N) . However, in order that these constituents can be made available to the body, proteins must first be degraded during digestion and absorbed in the body in a useful form.

Ruminants, such as cows, have a number of rumina . In these rumina the proteins are degraded by micro-organisms to ammonia and organic acids which are utilized partially for the production of microbial protein. However, part of the released nitrogen in the form of ammonia is not further utilized but absorbed into the bloodstream as urea and excreted via the urine. The result hereof is a loss of protein and nitrogen and moreover, in extreme conditions, a negative effect on the health of the animal as a consequence of high concentrations of urea in the blood. In order to prevent degradation of proteins in the rumina, whereby the proteins will reach the stomach itself substantially intact, where degradation of proteins into a useful form does take place, a number of treatments have already been proposed, such as a heat treatment or a chemical treatment. The object of such treatments is always to improve the resistance of proteins to degradation, which amounts in practice to bringing the proteins into a form inaccessible to protein- degrading micro-organisms in the rumina. However, the methods used heretofore have as yet been found to be insufficiently effective with some products in obtaining an optimal or at least acceptable protein utilization .^" It is therefore the object of the invention to provide a new method with which the resistance to degradation of proteins in the rumina of ruminants is improved, whereby the total protein utilization by the animal is augmented.

This is achieved by the invention by a method comprising the steps of: a) providing seeds that are reduced in size, so-called seed parts; b) subjecting the seed parts to a heat treatment ; c) flaking the treated seed parts; d) optionally cooling and/or drying the flakes; and e) treating the flakes with formaldehyde.

In this application "seeds" are also understood to include pulses .

It has been found in research that seeds treated in this manner, when compared to untreated seeds or to seeds which are only reduced in size and chemically treated, have a significantly improved resistance to degradation of 20 to 40%. The provision of seeds which are reduced in size (seed parts) can take place in different ways, for example by breaking intact seeds, but also by taking as raw material seeds which are already broken or otherwise reduced in size. Size-reduction of the seeds is important in making the interior of the seeds accessible for further treatment steps.

The heat treatment of the seed parts is prefer- ably a steam treatment, which consists for instance of exposing" the size-reduced seeds to steam for a determined period and bringing the product to a temperature of at least 100°C. This type of treatment is also known per se as "toasting". The moisture content of the seeds is increased by approximately 6% by the steam treatment.

Alternatively, heat treatments such as expansion, extrusion, rotary drying etc. can also be used. After the _steam treatment the reduced seeds are flaked by means of flake rollers, the pressure of which, and thereby the flake thickness, can be determined hydraulically. Due to the steam treatment and the flaking there occurs destructurizing and surface enlargement of the product, whereby the reaction with formaldehyde is greatly improved.

After flaking the product is dried if necessary and cooled to a moisture content of about 13%. The form- aldehyde treatment consists of intensive admixing of a formaldehyde solution into the flaked product. The dosage of the formaldehyde solution is such that 0.3 to 0.5% pure formaldehyde is added to the treated product.

After addition of the formaldehyde solution the product is stored for at least 72 hours in a closed space to give the formaldehyde the opportunity to take effect. The formaldehyde reacts with the proteins which thereby pass through the rumina without being degraded. Degradation can however take place in the actual stomach due to the lower pH prevailing there. The eventual absorption efficiency and utilization of the proteins is hereby significantly increased.

The method according to the invention is suitable for improving the resistance of proteins to degrada- tion in a large number of proteinaceous seeds, such as those of papilionaceous flowers and those of crops providing vegetable oils. Examples of seeds which can be used in the method according to the invention are lupin seed, sunflower seed, soya beans and rape seed. Lupin seed is particularly recommended.

The invention further relates to the product obtained by performing the method according to the invention, i.e. the seed treated in this manner and the use of this seed in the manufacture of animal feeds, in particu- lar for ruminants such as cows.

Finally, the invention relates to animal feeds containing the product obtained with the method according to the invention, and the use thereof as semimanufacture for the preparation of mixed fodders for ruminants.

The invention will be further elucidated by way of the non-limitative examples following hereinbelow.

EXAMPLES

EXAMPLE 1

Treatment of lupin seed 30,000 kg of lupin seed was broken by a grinding roller and subsequently fed to a Kahl cascade-toaster, in which the broken seeds were treated with steam for 20 minutes and heated to a temperature of 102°C.

The toasted seeds were flaked with a Bύhler flaking roller at a pressure of 40 bar and subsequently dried in a belt dryer and cooled in a belt cooler.

In a rapid mixer a 30% formaldehyde solution was added in a dosage of 1.66% to the flakes obtained in this manner. After the addition of the formaldehyde solution the flakes were stored in a closed silo for 72 hours.

EXAMPLE 2

Determination of in vitro protein resistance The degradation of the protein of the product as manufactured in example 1 was determined in vitro in accordance with the method described by Assoumani, MB. et al. in Animal Feed Science and Technology, 39 (1992) 357- 368. The protease resistance of the protein amounted to 78% after 4 hours of incubation. In untreated lupins a protease resistance of 8% was measured and in lupins only reduced in size and treated with formaldehyde a protease resistance of 62% was found. The additional treatment of heating with steam and flaking resulted in a significant improvement in the in vitro-determined protease resistance of the protein. EXAMPLE 3

Determination of the protein resistance, digestibility and starch resistance in vivo

The in situ degradation of protein and starch of the product as manufactured in example 1 was determined in cows by incubation in the rumen. This test was performed in accordance with the Protocol for in situ incubations in the rumen of dairy cows formulated by the Central Cattle Feed Agency in the Netherlands. The residues of the rumen incubation were tested for digestibility using the mobile nylon bag technique .

By way of comparison, a lupin seed only reduced in size and treated with formaldehyde was also tested in this experiment and the results were also compared with untreated lupins .

The results of this experiment were as follows:

product resistance (%) digestibility

protein starch protein (%)

Lupins treated 67.0 37 98.6 as in example 1

Lupins reduced 49.3 34 98.6 and treated with formaldehyde

Untreated lupins 22 10 98

A significant improvement in the resistance of the protein due to the steam treatment and flaking of the lupin seed without a decrease in the digestibility was also determined in the in vivo test .

Claims

1. Method of improving the resistance to degradation of proteins in seeds for use in animal feeds, in particular for ruminants such as cows, comprising the steps of : a) providing seeds that are reduced in size, so-called seed parts; b) subjecting the seed parts to a heat treatment ; c) flaking the treated seed parts; d) optionally cooling and/or drying the flakes; and e) treating the flakes with formaldehyde.

2. Method as claimed in claim 1, characterized in that the provision of seeds reduced in size (seed parts) takes place by breaking intact seeds.

3. Method as claimed in claim 1 or 2 , characterized in that the heat treatment is a steam treatment which consists of exposing the seed parts to steam with a temperature of at least 100┬░C.

4. Method as claimed in claim 1 or 2 , characterized in that the formaldehyde treatment consists of intensive admixing of a formaldehyde solution in a concentration such that 0.3 - 0.5% formaldehyde is added to the product .

5. Method as claimed in any of the foregoing claims, wherein the seed is chosen from seeds of papilionaceous flowers or crops providing vegetable oils.

6. Method as claimed in claim 5, wherein the seeds are chosen from lupin seeds, sunflower seeds, soya beans or rape seed.

7. Product obtained by performing the method as claimed in any of the claims 1-6.

8. Product as claimed in claim 7, wherein the seed used is lupin seed.

9. Animal feed comprising a product as claimed in claim 7 or 8 intended for use as an ingredient in mixed fodder for ruminants.