Fermented meat trim and its incorporation in meat

Prior to incorporating meat trimmings into a meat piece, the trimmings are inoculated with starter culture and fermented with the bacteria from the culture to obtain fermented meat trim particles and then frozen for incorporation into a meat piece.

BACKGROUND OF THE INVENTION 
The present invention relates to incorporation of meat trimmings into meat. 
Meat trimmings are obtained from meat during the standard preparation of 
whole cuts of meat in the meat industry. The trimmings are usually, but 
not always, of low quality and usually contain some fat and some muscle 
tissue. It is possible, by using technology introduced onto the market in 
recent years, to incorporate suspensions made of meat trimmings into whole 
cuts of like meat to increase the weight using a multi-needle injector. By 
controlling parameters such as the amount of trimmings injected, the 
meat/fat ratio and the quality of the meat, this technology enables the 
production of cooked ham or other marinated meat products without 
affecting the standard quality with regard to flavour, shelf-life and lack 
of visibility of the suspension, and in some cases improving it, for 
instance, with regard to binding and yield. Such a process is described in 
U.S. Pat. No. 4,960,599. The cost saving of injecting trimmings is 
considerable when the trimmings are of low value compared to whole cuts of 
meat. 
In order to impart a specificity to the flavour and to improve 
microbiological stability, it has been proposed to ferment raw marinated 
meat by using a starter culture in a brine or marinade prior to cooking to 
produce bacteriocins. However, since the raw marinated meat can under no 
circumstances be allowed to ferment at a temperature higher than about 
+8.degree. C., the biggest problem is to find a starter culture that can 
produce bacteriocins and a specific flavour at low temperature. We have 
tested some commercially available cultures, but the effect on the final 
quality of the product regarding flavour and microbiological stability is 
minimal. In addition, the production time before the cooking step must be 
prolonged considerably. 
SUMMARY OF THE INVENTION 
We have found, surprisingly, that by fermenting meat trimmings with a 
bacteria prior to incorporation into meat, it is possible to adapt 
fermentation parameters such as temperature, time, humidity and 
ingredients, etc. to their optimal values. 
Accordingly, the present invention provides a process for preparing meat 
containing meat trimmings therein which comprises incorporating into a 
meat piece a suspension of meat trimmings in a brine, marinade, or pickle 
having a temperature which does not exceed 1.degree. C. and characterised 
in that before freezing, the meat trimmings are fermented with a bacteria. 
The present invention also includes the product of the process which is, 
thereby, a meat piece having incorporated therein bacterially-fermented 
meat trimmings. 
DETAILED DESCRIPTION OF THE INVENTION 
In carrying out the process of the present invention, the meat used may be 
obtained from all types of meat such as pork, beef, lamb, poultry and 
fish. Raw whole cuts of meat may be chilled, e.g. to a temperature from 
-2.degree. to 12.degree. C., preferably from 2.degree. to 10.degree. C. 
and especially from 3.degree. to 8.degree. C., and deboned, and the 
trimmings may be removed in the usual manner. The meat trimmings used 
preferably are those removed from the actual piece of meat to be treated, 
but it is also possible to use trimmings from the same type of meat as the 
meat to be treated. It is also possible to use trimmings from a type of 
meat other than the meat to be treated, although this is generally less 
preferred. 
The trimmings may be incorporated into trimmed whole meat cut pieces as 
such or into smaller portions of meat formed by dividing the whole meat 
cut pieces into smaller portion pieces having an average diameter of from 
0.5 to 10 cm, more conveniently from 1 to 5 cm. 
When the fermented meat trimmings are incorporated into whole cuts of meat, 
this may be carried out conventionally by injection, using, for instance, 
a multi-needle injector. When the meat trimmings are incorporated into 
smaller portions of meat, this may be carried out by mixing the meat 
trimmings with the smaller portions of meat, e.g. with agitation such as 
stirring or tumbling. For example, a suspension of the meat trimmings may 
be added directly to the meat pieces in a tumbler. 
Before fermentation, the meat trimmings are conveniently ground until the 
majority of the particles have a size of less than 30 mm diameter and have 
an average particle size of from 1 mm to 5 mm, preferably from 2 mm to 4 
mm diameter. 
Before, during or after the addition of a bacteria starter culture, the 
ground meat trimmings may be mixed with a brine, pickle, or marinate. As 
is well known, a pickle is used for preserving meat and may contain brine, 
or other salt, or vinegar or acid liquor, while a marinade is used for 
flavouring meat and may contain brine, vinegar or wine, oil, spices and 
herbs, etc. For instance, the ground meat trimmings may be mixed with 
sugar and a nitrite salt such as sodium nitrite. The pH of the mixture is 
usually in the range of from about 5.2 to 6.3, preferably from 5.5 to 6.0. 
Suitable bacteria providing starter cultures are species Lactobacillus, 
Streptococcus and Pediococcus and preferable strains are Lactobacillus 
sake and Pediococcus acidilacti and salami. Starter culture prepared with 
the bacteria may be mixed in water, as is conventional, before being added 
to the meat trimmings. The amount of starter culture used may be from 0.1 
to 10 ml, preferably from 0.5 to 5 ml and especially from 0.75 to 2.5 ml 
per kg of ground meat trimmings. The mixture of ground meat trimmings and 
the starter culture in the brine, pickle, or marinade is advantageously 
packed in a vessel or bin suitable for fermentation, such as a plastic bag 
or pouch, within which fermentation is allowed to proceed. The 
fermentation may take place at a temperature from 0.degree. to 55.degree. 
C., preferably from 8.degree. to 45.degree. C. and more preferably from 
15.degree. to 40.degree. C. over a period of from about 12 hours to about 
7 days, preferably from 18 hours to 5 days. During the early stages of the 
fermentation, e.g. after a period of from about 6 to 30 hours and more 
usually after a period of from 12 to 24 hours, the pH falls, for instance 
to a pH of from 5.2 to 5.3 or below. 
After the fermentation, the fermented ground meat trimmings are frozen, 
e.g. to a temperature from -5.degree. to -30.degree. C., preferably from 
-15.degree. to -25.degree. C. After freezing, the fermented ground meat 
trimmings are advantageously flaked, e.g. to particles having a maximum 
volume of about 2 cc, preferably a maximum volume of 1 cc. 
After freezing, a frozen brine, pickle, or marinade may be mixed with the 
fermented meat trimmings to form a suspension. The mixing may be performed 
by emulsifying one or more times, e.g. up to four times. The frozen brine 
may be at a temperature of from 0.degree. to -30.degree. C. and preferably 
from -5.degree. to -12.degree. C. The ratio of brine, pickle, or marinade 
to the fermented meat trimmings may be from 1:1 to 20:1, preferably from 
1.5:1 to 15:1 and more preferably from 2:1 to 9:1. For example, a brine 
may consist of a mixture of nitrite salt, sugar, ascorbate and water. The 
nitrite and ascorbate salts are conveniently the sodium salts. 
The suspension of meat trimmings in a brine, marinade, or pickle is then 
warmed to a temperature of not greater than +1.degree. C., for instance 
from about -2.degree. to -10.degree. C., preferably from -40.degree. to 
-8.degree. C., and incorporated into the chilled meat. The temperature of 
the suspension should not exceed +1.degree. C. since, otherwise, proteins 
would be extracted which would cause the suspension to thicken rapidly, 
and this may cause subsequent clogging of the needles when the meat 
trimmings are injected into the meat with needles. 
The amount of meat trimmings incorporated into the meat may be up to 15% by 
weight based upon the weight of the meat and may vary, e.g., conveniently 
from 1 to 10% and preferably from 2 to 6% by weight. During the 
incorporation of the suspension of the meat trimmings into the meat, 
especially by injection, a portion of the suspension of the meat trimmings 
is squeezed out of the meat and may be returned to the batch containing 
the mixture of trimmings with brine where it is chilled down again. Any 
portion of the suspension returned is preferably emulsified at least one, 
more preferably at least two or three times, with the next batch because 
it may contain small meat particles which are disrupted from the muscles 
during injection and which could cause clogging of the needles. When the 
meat trimmings are incorporated by injection, a part of the suspension of 
the meat trimmings preferably is added separately so that some may be 
absorbed during tumbling, since it is not usually possible to incorporate 
the exact desired percentage of suspension by injection. 
After the injection, the meat may be processed conventionally. 
The meat product may be a chilled product which is either non-cooked or 
cooked, or it may be frozen, preferably marinated, or dried. Examples of 
non-cooked chilled meat products are LARDON product, bacon, cold smoked 
ham, etc. An example of a cooked and chilled meat product is cooked ham. 
For a cooked, chilled product such as cooked ham, the meat may undergo 
tenderisation, tumbling, moulding, cooking, chilling, storage, slicing and 
packaging by conventional methods such as are well known in the art. The 
process of the present invention may provide protection against 
undesirable bacteria such as Listeria in chilled products and provide 
improved flavour in frozen and dried products.

EXAMPLES 
The following Examples further illustrate the present invention. Parts and 
percentages are by weight. 
Example 1 
A whole ham was chilled to 5.degree. C. and trimmed by removing fat, 
sinews, etc., before being separated into different whole meat cuts. The 
trimmings removed from the whole ham, i.e., the fat, sinews, etc., were 
ground in a Kilia grinder to an average particle size of 3 mm, mixed in a 
Hobart mixer with, per gram of trimmings, 2% dextrose, a mixture of 0.5% 
sodium nitrite and 0.5% sodium chloride, 1% sodium chloride, and 1.0% of a 
starter culture of L. sake containing 10.sup.6 -10.sup.7 bacteria. The 
mixture was packed into plastic pouches and fermented at 25.degree. C. for 
36 hours. The pH fell rapidly during the first day from an initial value 
of pH 6 to pH 5. 
After fermentation, the fermented mixture was packed into whole bags and 
frozen to -20.degree. C., flaked in a magurit flaker to particles having 
dimensions of 0.5.times.0.5.times.0.5 cm and warmed to -15.degree. C. A 
brine at -8.degree. C. composed of 10.08% sodium nitrite, 0.18% sodium 
ascorbate, 2.28% dextrose and 87.46% water (corresponding to an injection 
level of 40.5% and a 7% level of trimmings in the final product) was then 
mixed with the flakes of the fermented mixture in a ratio of 3 parts brine 
to 1 part flakes. The mixing was carried out by emulsifying three times to 
form a suspension. The suspension was then injected at -6.degree. C. into 
one of the whole cuts of ham through a multi-needle injector, and the ham 
containing the fermented meat trimmings was then subjected to 
tenderisation, tumbling, moulding, cooking, chilling, storage, slicing and 
finally packaging, by conventional methods. 
The chilled cooked ham had a longer shelf-life and an improved flavour 
compared with a similar product containing meat trimmings which had not 
been fermented. Furthermore, a similar product containing meat trimmings 
which had been fermented within the whole meat cut at 5.degree. C. had a 
shorter shelf-life and an inferior flavour compared with the chilled 
cooked ham product as prepared in Example 1. 
Example 2 
A similar process to that described in Example 1 was followed except that 
the injection level of the suspension was only 17.3%, instead of the 40.3% 
level used in Example 1, giving an addition of only 3% trimmings in the 
final product instead of 7% in Example 1. 
The chilled cooked ham had a longer shelf-life and an improved flavour 
compared with a similar product containing meat trimmings which had not 
been fermented. Furthermore, a similar product containing meat trimmings 
which had been fermented within the whole meat cut at 5.degree. C. had a 
shorter shelf-life and an inferior flavour compared with the chilled 
cooked ham product as prepared in Example 2.