Device for injecting a piece of meat with a liquid substance such as brine

A method and device for injecting liquid substances such as brine or paste into a piece of meat. During injection, the piece of meat, which is conveyed over a row of spray nozzles, is held in contact with a row of the nozzles, preferably by means of a pressure roller. The rotational shaft of the roller is situated opposite the row of spray nozzles. This allows for deforming the meat to a slab of predetermined thickness and prevents the injection stream from being atomized prematurely, that is, outside the meat. This results in a homogeneous distribution of the brining liquid in the meat.

BACKGROUND OF THE INVENTION 
The invention relates to a method for introducing liquid substances such as 
brine or paste into a meat piece, wherein the liquid substance is injected 
into the meat piece. 
The invention relates more particularly to the injecting of brining liquid 
into a piece of meat without needles or other mechanical means being 
inserted into the piece of meat. To this end the brining liquid is sprayed 
at high pressure from a spray nozzle into the meat which, in the known 
methods, results in the surface of the meat being damaged. 
The invention has for its object to improve the above mentioned method such 
that this damage does not occur. 
SUMMARY OF THE INVENTION 
The method according to the invention is distinguished in that during 
injecting the piece of meat is held in contact with one or more spray 
nozzles for injecting the liquid substance. 
The contact prevents the injection stream being atomized prematurely, that 
is, outside the meat, which would result in a greater spraying spot. 
According to a further development the meat piece is deformed using 
mechanical means to a slab of predetermined thickness and with a certain 
width. Owing to the deforming of the meat to a determined thickness the 
required injecting pressure is reduced, which also contributes towards 
reducing the damage to the meat surface. 
It is further recommended in each case to subject the meat piece according 
to a determined grid to at least one stream of liquid substance under 
superatmospheric pressure. The most homogeneous possible distribution of 
the brining liquid in the meat is thus obtained, wherein it is recommended 
according to the invention to make the grid size a maximum of 2 cm, and 
preferably 1 cm. 
To avoid damage to the meat, particularly red meat, the invention proposes 
to make the thickness of the meat piece for deforming a maximum of 2 cm so 
that with a penetration depth of 1 cm 50% of the meat is already cured. 
The invention further relates to a device for performing the above stated 
method, which device is provided with a frame and one or more spray 
nozzles for the liquid substance carried by the frame, which device is 
distinguished in that means are arranged for holding the piece of meat in 
contact with the or each spray nozzle. According to a further development 
of the device according to the invention it is embodied with means for 
deforming the piece of meat, in particular close to the spray nozzles. 
With such an embodiment the meat piece is carried along the spray nozzles 
whereby these latter can have a stationary disposition, which facilitates 
the supply of brining liquid under high pressure and control of the 
comparatively short spraying times. 
In a preferred embodiment the transporting means are embodied as a conveyor 
carrying the piece of meat. 
In preference the spray nozzles are disposed in a line perpendicular to the 
conveying direction of the meat piece, wherein the conveyor can be 
embodied as an endless belt whereof at least one reversing roller is 
arranged adjacent to the row of spray nozzles. 
According to the invention the deforming means can effectively be embodied 
as a pressure roller whereof the rotational shaft is situated opposite the 
row of spray nozzles. According to the invention this rotational shaft can 
be distance-adjustable relative to these spray nozzles. 
According to another embodiment the means for deforming the meat piece can 
be embodied as a pressure chamber having two substantially parallel walls, 
in the one of which the row of spray nozzles is arranged and the other 
wall whereof converges relative to the one wall towards the spray nozzles, 
and wherein the transporting means is a piston movable reciprocally 
between the two walls.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The device according to FIG. 1 consists of a frame 1 of random type, which 
in the embodiment shown is made from tube profiles, this such that two 
endless conveyors 2, 3 can be supported in line with one another. Received 
between the two conveyors 2, 3 is a beam 4 having arranged therein spray 
nozzles to be further elucidated hereinafter, this such that these are 
arranged in a line perpendicular to the conveying direction P1. A pressure 
roller 5 which serves as deforming means for the meat is rotatably 
arranged opposite and above the beam 4, wherein it is noted that the 
rotational shaft of the roller 5 is received at either end in each case in 
a swivel arm 6. 
With reference to FIG. 2 and 3, the spray beam 4 is embodied as a beam of 
trapezium-shaped cross section having a number of vertical bores in each 
of which is received a spray nozzle 10. The bores communicate on the 
underside with a common feed channel 11 which communicates with a feed 
conduit 12 which is connected in a manner to be designated below to a 
liquid feed system 13. The spray nozzle beam 4 is held in two frame beams 
14 which form part of the main frame 1. 
In the embodiment shown the feed conveyor 2 is an endless belt 15 provided 
with a reversing member 16 extending parallel and close to the side of the 
spray nozzle beam 4. The belt 15 is further trained around a tensioning or 
drive roller 17 with associated guide rollers 18. On the feed side the 
belt is embodied with a second reversing roller 19. 
The discharge conveyor 3 is embodied in similar manner, with the 
understanding that it is arranged mirror symmetrically metrically relative 
to the spray nozzle beam 4. The driving of both conveyors takes place such 
that the upper part moves in the direction of the arrow Pl. 
The roller 5 embodied with a covering of elastic material can be of any 
type but is of a weight and is biased in the direction of the arrow P2 
such that a meat piece V to be moved forward on the conveyor is subjected 
to a determined pressure such that the piece of meat undergoes a deforming 
at the position of the spray nozzle beam 4, whereby the thickness is 
reduced. 
As already stated above, the roller 5 is freely rotatable on a rotational 
shaft 5' which is mounted in swivel arms 6 which are mutually connected 
with a coupling shaft 20 which is received in a fork-like bearing part 21 
which supports on the frame 1. The coupling shaft 20 runs through beneath 
the upper part of conveyor 2. If use is made of a determined biasing of 
the roller 5 in the direction of the spray nozzle beam 4, hydraulic 
cylinders (not shown) can then act upon the arms 6. 
There now follows a description of the liquid feed system, the liquid 
whereof serves as injection liquid for the meat piece V. 
Arranged under the spray nozzle beam 4 is a valve housing 25 of which the 
intake opening 26 is connected to a feed conduit 27 for the injection 
liquid, for example brine with additives, subject to the meat piece for 
processing. 
Arranged in the valve housing 25 is a non-return valve in addition to a 
non-return valve 29. Each non-return valve is embodied here as a ball that 
is movable in a chamber and which can close off and release a passage 
opening located thereunder. 
Arranged between both ball valves 28 and 29 in the passage 30 of the valve 
housing 25 is a branch bore 31 in which a plunger 32 is reciprocally 
movable. In the embodiment of FIG. 2 the plunger is driven by a hydraulic 
cylinder 33 by connecting the piston rod 34 thereof via a coupling 35 to 
the plunger end part 36 of plunger 32. 
Finally, it is noted that the outlet port of the upper valve part 29 is 
connected to the inlet bore 12 of the spray nozzle beam 4. 
The above device operates as follows. 
When a randomly shaped piece of meat is laid on the upper part of the feed 
conveyor 2 it is carried in the direction of arrow Pl to the spray nozzle 
beam 4. At this location the piece of meat V is brought to the correct 
thickness by the pressure roller 5 and liquid in the spray nozzles 10 is 
in each case sprayed, preferably every centimeter as seen in the direction 
of arrow Pl, into the meat on the underside. Spraying takes place for a 
very short time, between 12 and 60 milliseconds, in order to prevent 
stripes on the underside of meat piece V. With a correct distance interval 
between the spray nozzles 10, for instance 1 cm, a one centimeter grid can 
be obtained, see FIG. 5. By selecting the correct spraying pressure and 
spray velocity a good penetration depth of the liquid into the meat V can 
already be achieved, whereby the meat is contaminated not only regularly 
but also uniformly, see the concentric circles around the spraying 
positions in the grid according to FIG. 5. A uniform distribution of the 
brining liquid in the meat V is herewith assured. 
Spraying of the liquid is effected by periodically moving the plunger 32 
reciprocally in the branch chamber 31 of the valve housing 25. This is 
carried out in one case by actuating the cylinder 33 according to FIG. 2 
and in the other by the motor 39 as in FIG. 3. 
When the plunger 32 moves to the left liquid will be drawn via the lower 
valve 28 into the chamber 30, wherein after the plunger 32 has moved back 
the liquid in chamber 30 is placed under pressure, which results in the 
closing of the lower valve 28 and the opening of the upper valve 29, 
whereby the liquid can flow via opening 12 and channel 11 to the spray 
nozzle beam, whereafter it can exit to the outside via the spray nozzles 
10. 
Owing to the direct contact of the outflow opening of the spray nozzle 10 
with the underside of the meat piece V the bottom surface of the meat 
piece V will not be damaged. 
Shown below is a survey of test results on different sorts of meat. 
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Chicken fillet: 
required pressure 
90 bar 
sprayer orifice 
0.13 mm 
penetration to 
15 mm 
weight increase 
4-15% 
maximum increase 
25% 
Chicken legs: required pressure 
70-90 bar 
sprayer orifice 
0.13 mm 
penetration depth 
10-15 mm 
weight increase 
4-15% 
maximum increase 
20% 
Pork: required pressure 
200 bar 
(shoulder) sprayer orifice 
0.13 mm 
penetration depth 
25 mm 
weight increase 
4-30% 
maximum increase 
25% 
Pork: required pressure 
250 bar 
(bacon backs) sprayer orifice 
0.13 mm 
penetration depth 
30 mm 
weight increase 
4-20% 
maximum increase 
25% 
Salmon: required pressure 
60-80 bar 
(smoked salmon) 
sprayer orifice 
0.13 mm 
penetration depth 
20 mm 
weight increase 
3-7% 
maximum increase 
5% 
______________________________________ 
There now follows a description of an alternative embodiment according to 
FIG. 4. In the schematic depiction of this embodiment the spray nozzle 
beam 4 and the discharge conveyor 3 are the only similarities to the 
embodiment of FIG. 1-3. The spray nozzle beam 4 forms part of the bottom 
wall 40 of a pressure chamber 41, the top wall 42 of which extends 
parallel to the bottom wall 40. The sides of the pressure chamber 41 are 
closed by fixed wall portions (not shown). In the pressure chamber 41 a 
rectangular piston 43 is reciprocally movable by a hydraulic cylinder 44. 
The wall 42 located opposite the bottom wall 40 converges from the point 
45 in the direction of the spray nozzle beam 4, whereby a narrow passage 
opening is obtained at the position of the spray nozzles. Behind the spray 
nozzle beam 4 the pressure chamber widens again, wherein the open rear 
part debouches above the upper part of the discharge conveyor 3. 
The device operates as follows: By actuating the hydraulic cylinder 44 the 
rectangular piston 43 will move to the right in FIG. 4, whereby the piece 
of meat pre-arranged in the pressure chamber 41 is transported in the 
direction of arrow P1 and pressed through the narrow opening at the spray 
nozzle beam 4, whereby a deforming of the meat piece takes place to the 
desired thickness. The operation of the spray nozzle beam 4 can take place 
in a manner corresponding to that described above whereby the meat piece 
can be processed in accordance with the same grid pattern as in FIG. 5. 
The piece of meat V is further carried away on the discharge conveyor 3. 
The invention is not limited to the above described embodiments, wherein a 
kinematic reversal of the movement of the meat relative to the spray 
nozzles is conceivable. It is equally possible in a particular embodiment 
to move the spray nozzles relative to the stationary piece of meat V in 
order to obtain the desired spraying grid. 
In addition the spray nozzles do not have to be disposed in a line but may 
have any suitable configuration. It is furthermore conceivable to arrange 
the spray nozzle movably in two coordinate axes whereby one spray nozzle 
would be sufficient. 
The common feed chamber for all spray nozzles can of course be replaced by 
a separate feed for each nozzle, thus enabling volume control per nozzle.