Poultry processing.

DESCRIPTION

The present invention relates to an improvement in the treatment of poultry processing, by incorporating an additive in the scalding water used during said processing.

It is well known that during the processing of poultry processing in general, once slaughtered and bled birds are passed through a tank of scalding water maintained at a temperature of, for example, 50-60 ^ C. This treatment loosen the feathers before the next stage of processing consisting of plucking itself.

It has been observed that at the beginning of a normal working process for the treatment of bird processing, the number of microorganisms found in such birds, prior to treatment with scalding water, is significantly reduced after such treatment. However, as the rate progresses, said reduction in the number of microorganisms from before treatment until after treatment becomes insignificant as a result of the accumulation of microorganisms in the scalding water. This greater bacterial concentration existing in the skeleton of the animal and that penetrates the plucking machines, brings with it a greater contamination of the skin of plucked poultry.

It is well known that bacteria located in the bird's skin are more resistant than those found in the free state. Therefore, any bacteria that survive treatment with scalding water would be very difficult to eliminate during subsequent processing (see the article by Notermans, S. et al in British Poultry Science, 1975, 16, pp 351-361).

One of the most dangerous infections of this type is salmonellosis caused by Salmonella typhimurium. Another type of microorganism Campylobacter jejuni.

Recent studies have also shown that the incidence of food poisoning outbreaks, associated with Campylobacter jejuni, has increased significantly in recent years.

Since these microorganisms are also found in the scalding water, it is necessary to reduce the effects of these organisms to mony. Many attempts have been made to reduce salmonella contamination.

The use of chlorine has been effective, but it has the disadvantage of producing bad odors, undesirable flavors and coloration of the products.

Control by decontamination of the final product has also been suggested. However, this measure introduces another stage of processing and it has not been possible to test the efficiency of this method. Again, the already proposed use of lactic acid, if it is effective, not only causes undesirable coloration of the product at concentrations above 0.25%, but also adversely affects the texture of the meat in the case that scalding is incorporated into the water.

Likewise, it has been suggested to increase the pH of the scalding water to a value of approximately 9. Although at normal scalding times of 2.5-4 minutes, this treatment reduces the number of potential pathogens, it fails to eliminate them (see the article by Humprhrey, TJ et al in J. of Applied Bacteriology, 1984, 57 , pp 355-359).

It has now been found that these undesirable microorganisms can be substantially eliminated by the use of an acidic salt in the scalding water tank.

Consequently, the present invention consists of a method for the treatment of poultry processing, the processing of which comprises the step of submerging the skeleton of the birds in a tank of scalding water prior to plucking, said method being characterized in that in the water of Scalded incorporates an effective amount of an acidic polyphormate salt.

By the term "acidic polyphomate salt" is meant throughout this description that in the salt the ratio of chemical equivalents of the format anioon to a cationon other than hydrogen is at least 4: 1.

The acidic polyphormate is preferably tetra ammonic format.

The effective amount of acidic polyphormate used depended on the type and quality of the birds to be treated as well as the temperature of the scalding water. Thus, for a scalding water temperature of 50-60 ^ C, the amount of acidic polyphormate salt used is suitably 0.002 to 0.5% by weight of the tank water, preferably 0.005 to 0.2 % in weigh.

Those skilled in the art understood that the acidic polyphormate need not be incorporated into the scalding water tank as a previously formed salt. For example, it could be added as two or more reactant components that together will lead to a concentration and a cation-to-anion ratio corresponding to that of the acidic polyphormate salt that is only scalding.

Through the use of the additives followed by the present invention it has been found that, at suitable concentrations, said additives are effective even in the presence of other organic material that hitherto had adversely affected the techniques previously employed. Similarly, microorganisms have been proactively removed from scalding water.

The present invention is further illustrated with reference to the following examples. Preliminary evaluation of ammonium tetraformate (ATF) as a potential additive for water from scalding birds

The following work was carried out under laboratory conditions.

A strain of Campylobacter jejuni, biotype 2, originally isolated from a chicken, was subjected to various concentrations of ATF at a temperature of 50 C for 3 minutes to simulate the "soft" scalding process used commercially.

Initially, tests were carried out using water alone and the percentage reduction of the number of campylobacters was calculated in each case. The experiment was repeated with the addition of 1% horse serum or skim milk, to provide an "organic load" analogous to

019 637 which is produced in natural scalding water.

All trials were repeated four times and, in each case, the average count reduction was expressed as a percentage:

<td>Conc. Of ATF (ppm)</td><td>Water alone</td><td>With organic load</td>

<td> 5</td><td> 30,82</td><td> 12,90</td>

<td> 10</td><td> 38,34</td><td> 25,87</td>

<td> 25</td><td> 99,92</td><td> 38,34</td>

<td> 50</td><td> &gt;99,99</td><td> 96,37</td>

<td> 100</td><td> &gt;99,99</td><td> 99,99</td>

The above reductions were calculated after the effects of heat occurred only, that is, 50 ^ C / 3 minutes and, therefore, are only attributable to the activity of ATF itself.

The previous results show that ATF was effective in destroying C. jejuni at relatively high solutions and that organic materials at a level of up to 1% had only a slight effect in reducing ATF activity.

Effect of ammonium tetraformate (ATF) at 5 (0 C for 3 minutes on Salmonella agona

The procedure described above will be followed again, except that Salmonella agona was used as the test organism instead of Campylobacter jejuni. The results are expressed as the average percentage reduction in the count:

<td>Conc. Of ATF (ppm)</td><td>Water alone</td><td>With organic load</td>

<td> 100</td><td> 17,9</td><td> 17,5</td>

<td> 250</td><td> 30,1</td><td> 45,0</td>

<td> 500</td><td> 66,3</td><td> 84,1</td>

<td> 1000</td><td> &gt;95,0</td><td> &gt;95,0</td>

The above reduction percentages were calculated after only allowing the effects of heat, that is, 50 C / 3 minutes, consequently they are uniquely attributable to ATF activity.

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