BLOOD CHUNKS

ALIMENTS EN MORCEAUX POUR ANIMAUX A BASE DE SANG

English Abstract

The invention provides a method of manufacturing a blood chunk. The method
comprises heating a blood fraction, adding hydrogen peroxide, and compressing
the resulting reaction product to form a chunk having a laminar structure. An
edible chunk comprising a major proportion of blood protein and having a
fibrous, laminar internal structure is also described.

French Abstract

L'invention concerne un procédé de fabrication d'aliments en morceaux pour animaux à base de sang. Ledit procédé consiste à chauffer une partie du sang; à ajouter du peroxyde d'hydrogène; et à comprimer le produit de réaction obtenu pour former des morceaux à structure lamellaire. L'invention concerne également des aliments en morceaux comestibles à structure interne lamellaire fibreuse composés essentiellement de protéines sanguines.

Claims

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CLAIMS
1. A method of manufacturing a blood chunk comprising:
heating a blood fraction (as herein defined); adding
hydrogen peroxide; and compressing the resulting reaction
product to form a chunk having a laminar structure.
2. A method according to claim 1 in which the blood
fraction is a haemoglobin fraction (as herein defined).
3. A method according to claim 1 or 2 in which the
compression is carried out at a temperature greater than
60°C.
9. A method according to any preceding claim in which the
compressed product is dried.
5. A method according to any preceding claim further
comprising steaming the reaction product of the blood
fraction and the hydrogen peroxide.
6. A method according to any preceding claim in which the
hydrogen peroxide is added to the blood fraction at at least
0.5% (by weight).
7. A method according to any preceding claim in which the
blood fraction is heated to between 60°C and 80°C before
addition of the hydrogen peroxide.
8. A method according to any preceding claim in which the
blood fraction comprises at least 10%, preferably at least
15%, protein by weight.
9. An edible chunk comprising a major proportion of blood
protein and having a fibrous, laminar internal structure.

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10. A method substantially as described.
11. A chunk substantially as described.

Description

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BLOOD CHUNKS
The present invention relates to the preparation of a novel
edible chunk comprising blood, and to the chunk itself.
Blood and blood fractions are used in the manufacture of pet
foods as a nutrient. In particular, the h~noglobin fraction
of whole blood is employed; by the hemoglobin fraction is
meant the residue from whole blood once the plasma, or most
of the plasma, has been removed. '~'he haemoglobin fraction
consists of red and white blood ells with a residue of
plasma. The hemoglobin fraction typically contains from
about 14% to 40% protein and about 35% to 45% red blood
cells. The remainder is mainly water together with other
blood components.
Conventionally, whole blood is heated by scraped surface
heating or steam infusion to 75°C and treated with hydrogen
peroxide to decolour it. The decoloured blood is dewatered
2o to give a powder. In alternative techniques, whole blood is
coagulated with for example a solution containing calcium
ions and the resulting coagulate cut into chunks. Such
chunks are homogeneous in texture, resembling liver.
It has now been found that if a blood fraction, defined
herein as comprising from about 14% to about 40% protein and
about 35% to 45% red blood cells, is heated and treated with
hydrogen peroxide a solid foam results. The foam reaction
product can be cut into chunks and incorporated into, for
example, pet food. If the foam reaction product is
compressed, a textured solid mass is produced. The
compressed solid mass has a laminar structure similar to
that of cooked meat.
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The blood fraction may be formed in any way. The blood
fraction may be the haemoglobin fraction of blood.
Alternatively, the blood fraction may be formed by removing
water from whole blood to concentrate it so that it
comprises from about 14$ to about 40~ protein and about 35~
to 45$ red blood cells. The blood fraction may be
reconstituted from purified protein and red blood cells.
According to the invention there is provided a method of
1o forming a blood chunk comprising heating a blood fraction
(as defined above), treating the heated blood fraction with
hydrogen peroxide and compressing the resulting reaction
product to form a chunk having a laminar structure.
Preferably the blood fraction is a haemoglobin fraction (as
defined above).
Preferably the hydrogen peroxide is added to the blood
fraction at at least 0.5$ by weight. There does not appear
to be a significant upper limit to the concentration of
hydrogen peroxide in the reaction mixture which is effective
2o to cause the desired reaction to take place; concentrations
of up to 30 (by weight) have been found satisfactory.
Preferably, compression is carried out at a temperature
greater than 60°C.
Preferably the blood fraction is heated to between 60°C and
80°C before addition of the hydrogen peroxide.
Preferably the blood fraction comprises at least about 10~,
more preferably at least about 15$, by weight protein. At
lower protein concentrations, the reaction product does not
absorb all the water present in the reaction mixture. Such
products are useful and their manufacture falls within the
scope of the present invention; however, it will usually be
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necessary to remove the proteinaceous material from the
unabsorbed water before it is used.
Additives may be included in the blood fraction to modify
s the nutritional content and flavour of the chunks. It is
preferred that the pH of the blood fraction is no less than
4, and that it is no greater than 9.
Compression of the reaction product of the blood fraction
and hydrogen peroxide can be carried out on the reaction
1o product as it is formed, or the reaction product can be
stored and then subjected to heating, for example by
microwave radiation, prior to compressing. Alternatively,
the reaction product may be steamed to give a product having
a jelly-like texture. The steaming can be carried out with
15 meat juices or other flavoured aqueous media to impart
particular flavours to the product.
The product can be dried, preferably at about 60°C, to
produce hard, crunchy chunks, which are useful as a dry pet
food.
2o The reaction product of the blood fraction and hydrogen
peroxide can be compressed under its own weight.
The reaction product may be compressed as a result of
restriction of any expansion of the reaction product caused
by evolution of gas as the blood fraction and hydrogen
25 peroxide react.
The pressure at which the reaction product of the blood
fraction and hydrogen peroxide is compressed to achieve the
laminar internal structure is not critical; a pressure of up
to about 400 kPa is preferred.
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_ g _
Also according to the invention there is provided an edible
chunk comprising a major amount of blood protein and having
a fibrous, laminar internal structure.
The invention will be further described, by way of example,
with reference to the drawings in which;
Figure 1 shows schematically a method according to a first
embodiment of the invention;
Figure 2 shows schematically a method according to a second
1o embodiment of the invention; and
Figure 3 shows schematically a method according to a third
embodiment of the invention.
The methods according to the invention shown in the drawings
include the following common features. The hemoglobin
fraction of blood is pumped from a tank 10 by a peristaltic
pump 12 to a steam infuser 14 where the haemoglobin is heated
to about 75°C. The heated haemoglobin passes from the steam
infuser 14 to a high shear mixer reactor 16, such as a
Dispax reactor. In the Dispax reactor, the hxmoglobin is
2o reacted with hydrogen peroxide pumped from a hydrogen
peroxide tank 18 by a hydrogen peroxide .pump 20. In the
reactor 16, the hemoglobin and the hydrogen peroxide are
mixed efficiently. Preferably, the reactor is a high shear,
low volume mixer to ensure adequate mixing of the two
components.
In the first embodiment of the invention, shown in Figure 1,
the foam reaction product 22 is deposited in a tray 24. The
reaction product 22 can be allowed to be compressed by its
own weight, in which case the solid mass produced is elastic
3o and can be cut up to provide elastic chunks. Alternatively,
pressure can be applied to the reaction product 22 in the
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tray by application of a pressure plate 26. On release of
the pressure plate a solid product 28 having a fibrous,
laminar internal structure is produced, which can then be
cut into chunks 30 as at 32.
In the second embodiment of the invention, shown in Figure
2, the reaction product 22 from the reactor 16 is passed to
a piston pump 40 in which the reaction product is
compressed. As the reaction product 22 leaves the piston
pump 40, it is diced as at 42 to produce chunks 44 having a
1o fibrous, laminar internal structure.
In the third embodiment of the invention, shown in Figure 3,
the reaction product 22 leaves the reactor 16 through a
disperser 50, from where it passes into a mouth formed by
the widely separated ends of two converging continuous belts
52, 44. The reaction product is compressed between the two
continuous belts, and the resulting solid sheet 56 is cut
into chunks 58 as it leaves the continuous belts 52, 54, as
at 60. Again, the chunks produced have a fibrous, laminar
internal structure.
2o The chunks have a fibrous, laminar internal structure,
similar to that of meat chunks, so that the chunks can be
readily used in canned food stuffs such as pet foods to
provide a protein source which is analogous in appearance
and texture to meat.
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