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Protocol for Evaluating Retained Water
in the Following Single Ingredient Red Meat Product: Steer/Heifer Carcasses

Note: The following is an example protocol and should not to be used verbatim. Because each establishment is unique, each establishment should design their protocol to reflect the individual characteristics of their operations.


1.0    Purpose Statement

         1.1    The purpose of this protocol is to determine the amount of
                   water absorption and retention in Steer/Heifer carcasses that
                   is unavoidable while achieving the regulatory pathogen
                   reduction performance standard for Salmonella (as set forth
                   in the PR/HACCP regulations 9 CFR 310.25(b).

2.0    Type of washing and chilling system

         2.1    The facility slaughter/dressing line utilizes a final carcass
                  washer at the end of the dressing procedures. This is    
                  followed by a carcass rinses that includes the antimicrobial
                  intervention (*insert example) prior to entry into the carcass
                  cooler. The carcass cooler is maintained around 34 F.

3.0    Configuration and modification of the chiller system

        3.1    The establishment uses a carcass water spray system in the
                 carcass cooler to chill carcasses rapidly. The carcass water
                 spray system consists of intermittent sprays of water during
                 the carcass cooling process.

4.0    Special features in the chilling process:

    4.1    Chlorine is added to the carcass water spray as an
             antimicrobial intervention at 20-50 PPM. The carcasses
             freely drain before exiting the carcass cooler and prior to
             further processing in the establishment or prior to shipping.

5.0    Variable factors that affect water absorption and retention

    5.1    The final carcass wash cabinet consists of a number of spray
             nozzles at a selected pressure at selected spray directions by
             the establishment. The final carcass wash water is the normal
             ambient water temperature from the municipality or of the
             well water. The number and size of spray nozzles, direction
             of nozzles, water pressure, and the length of time in the final
             wash cabinet may be changed depending upon the size of the
             carcasses, season of the year, and changes in the dressing
             procedures. The carcasses are in the chiller system (cooler)
             usually from 18 to 24 hours. The carcass cooler temperature
             is usually maintained around 34 F. The temperature of the
             water in the carcass water spray is the normal ambient water
             temperature from the municipality or of the well water. The
             frequency and length of intermittent sprays of water per bay
             during the carcass cooling, the carcass cooler temperature
             and the drain time from the last spray prior to exiting the
             cooler may be varied.

6.0    Standards to be met by the chilling system:

        6.1    The current FSIS Salmonella pathogen reduction
                 performance standards, as set forth in the PR/HACCP final
                 rule, will be met.

7.0    Testing methodology

        7.1    Water absorption and retention

                 7.1.1    Samples will be collected immediately prior to the final
                             carcass wash on the slaughter/dressing line to
                             determine the "green" weight of the carcasses.

                       *(insert number) random carcasses will be
                                            tagged and weighed in *(insert number)
                                            groups of *(insert number) carcasses. The
                                            *(insert number) groups will be distributed
                                            evenly throughout the production period
                                            (beginning, middle, and end) with the
                                            production period being defined as
                                            sanitation to sanitation.

                7.1.2   Samples will be collected from carcasses at point
                            exiting the cooler.

                      The tagged carcasses from will be
                                            weighed immediately prior to further
                                            processing or shipping.

                      These post-cooler weights will be
                                            compared  to the pre-final carcass wash
                                            weights to determine the retained water
                                            gained using a mathematical difference
                                            calculation (cooler exit weight minus "green"
                                            weight [pre-final carcass wash weight]) as a

       7.2    Pathogen reduction measurement

                7.2.1    *(insert number) groups of *(insert number) carcasses
                             will be randomly selected post-cooler from the same
                             lots as those tested in Section 7.1. The *(insert
                             number) groups will be distributed evenly throughout
                             the production period (beginning, middle, and end)
                             with the production period being defined as sanitation
                             to sanitation.

                      The percent Salmonella positive rate will    
                                            be determined using the post-cooler
                                            carcass swabs Salmonella performance
                                            standard methodology.

        7.3    Evaluation of cooler factors

                 7.3.1   The frequency and length of intermittent carcass
                            sprays per cooler bay

                     Three frequency and length of sprays will be

                                     Fifteen minute interval: Spray for
                                                             1 minute, spray off for 14

                                     Thirty minute interval: spray for
                                                             3 minutes, spray off for 27

                                     Sixty minute interval: spray for 3
                                                             minutes, spray off  for 57

                7.3.2    The carcass cooler temperature will remain around
                            34 F.

                7.3.3    The drain time from the last carcass spray until exit

                      Two drain times will be evaluated.

                              4 hours after last spray

                              6 hours after last spray

                7.3.4    Study design

                      A three-by-two factorial table will be used
                                           to evaluate the effect of these cooler factor
                                           settings on the percent moisture retention
                                           (Section 7.1) and on the pathogen reduction
                                           measurements (Section 7.2).

                       Each of the six cooler setting combinations
                                            will be evaluated for three processing
                                            periods (defined as sanitation to sanitation).
                                            Each processing period will be considered
                                            a replicate.

8.0    Evaluation and Reporting of Data

         8.1   The results achieved from the three replicates per cooler
                  setting combination will be averaged and reported as the final
                  result for each cooler setting combination.

                  8.1.1    Carcass weight differences will be determined using a
                              mathematical difference calculation (cooler exit
                              weight minus "green" weight) for each carcass group
                              resulting in recorded weight difference results. The
                              weight difference obtained per carcass group will be
                              divided by the "green" weight per carcass group to
                              determine the % moisture retention cooler exit per
                              group. The results will be averaged to obtain the
                              estimated average % moisture retention at point of
                              cooler exit.

                8.1.2    The Salmonella data will be reported as the number
                            of positive samples/number of samples tested x 100
                            (% positive).

9.0    Explanation of how the conclusions will be determined.

        9.1    Conclusions will be determined by comparing the baseline
                  pathogen reduction levels achieved pre-protocol
                  implementation with the post-protocol implementation
                  pathogen reduction results. This comparison will be evaluated
                  according to the specifications detailed in section 6.1.

         9.2    The amount of moisture retention that is unavoidable to
                  achieve the above food safety criteria will be reported.

(*) Each establishment should insert statistically significant and verifiable information that reflects their unique operations.


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Last modified: February 09, 2004