The accuracy of the reference - test results.

Hans Busk

Objective

The objective of workpackage 1, task 1, was to describe the accuracy of the EU reference dissection, and to describe the types of the errors, and assess their size.

Materials and methods

The dissections were carried out in 4 countries by a team of 8 butchers. The pigs were selected in 3 fatgroups and randomly according to sex. In total 128 carcasses (256 halves) were selected and both  halves were dissected. The butchers has in pairs dissected one carcass (two halves), and the combination of butchers has changed each day. Documentation of the types of the pigs has been carried out by different measurements and by photos.

Results

The selection of carcasses at the abattoirs has been difficult, partly because of grouping of the carcasses into fatclasses, but mostly because of a poor splitting and deviant slaughter condition.

The facilities for dissections were satisfactory. The temperature in the room was low and there was enough space to prevent mix of the different cuts.

According to the experimental design, the following characters have been used in the model for evaluation of the different effects:

Y = constant + country + fatgroup(country) + abattoir(country) + sex(country) + side + weight + butcher + carcass(country) + e

Lean meat percentage

Differences between lean meat percentage contribute to the explanation of the accuracy of dissection of the carcasses. Table 3 shows some results for lean meat percentage in some joints and in the carcass.

Table 3. Effect of butcher (sF) and carcass (sH). Variation of repeatability sr and reproducibility sR.   

              Reliability of the method.

 

sF

sH

sr

sR

Reliability

 

Shoulder. Lean meat %

1.13

2.30

0.98

1.50

0.70

Belly. Lean meat %

1.43

3.47

1.30

1.94

0.76

Loin. Lean meat %

0.69

3.12

1.08

1.29

0.85

Leg. Lean meat %

0.45

2.57

0.67

0.81

0.91

Carcass (EU). Lean meat %

0.68

2.81

0.87

1.10

0.87

 

Experiences and conclusions

The calculations have not been finished yet, and therefore a final conclusion cannot be given. Some experiences from running the experiment and some preliminary conclusions can be given.

  1. It is difficult to select carcasses at the abattoirs which have a slaughter condition as described for the reference dissection.
  2. We have succeeded in selecting the carcasses according to the experimental plan (i.e.fat classes, sex, weigt).
  3. Jointing of the carcasses in accordance with the instruction is difficult, specially for the shoulder (low reliability).
  4. Dissection of the joints is satisfying (reliability > 0.80).
  5. The reproducibility variation for lean meat percentage is 1.10.