EFFECT OF BLEEDING METHODS ON MEAT QUALITY IN PIGS

The effect of bleeding in hanging (n = 140) and lying (n = 164) position after electrical stunning on meat quality in pigs was examined in a commercial slaughterhouse. The period between stunning and bleeding in hanging and lying position was reduced from approximately 25 sec to 10 sec respectively. All animals were suspended by the left leg and had the same genetic origin (Pietrain x (German Landrace x German Yorkshire). The pH-values 50 min p.m. (pH1) and the muscle conductivity 50 min p.m. (LF1) in ham and loin in the left and right half carcass were measured. Bleeding in lying position improved the average pH1-values in ham and loin in both half carcasses by approximately one standard deviation. This caused a reduction of proportion of PSE-meat (pH1 < 5,8) in loin in the left and right half carcass from 62,1 to 27,4 % and 62,9 to 22,0 % respectively. The average muscle conductivity was improved by bleeding in lying position in all muscles as well. Remarkable was the clearly increased average LF1-value in the left (suspended) ham at bleeding in hanging position. The positive effect of bleeding in lying position in this study has to be interpreted as a result of the entire changing measures (bleeding in lying position, new electrical stunning tongs, slightly modified gateway to restrainer).