Effect of stunning current frequency on carcass downgrading and meat quality of turkey
Résumé
The objective of this study was to determine
the effect of frequency of a 150 mA water-bath stunning
current on turkey hen carcass and meat qualities.
Fifty turkey hens were subjected to water-bath stunning
with alternating current of various frequencies: 50 Hz (n
= 12), 300 Hz (n = 14), 480 Hz (n = 12), and 600 Hz (n =
12); the duration of stunning was 4 s for each bird. Carcass
defects such as engorged wing veins, red wing tips, and
hemorrhages were recorded. Turkey meat quality traits
(M. Pectoralis major) were assessed based on rigor mortis
development, color, drip loss, cooking loss, tenderness, and cooking yield of cured products. The data showed
that frequencies of 480 Hz and 600 Hz are associated
with an increased rate of postmortem pH decline (during
bleeding). This effect is most likely due to the occurrence
of vigorous wing flapping during the first 3min poststunning.
Under the experimental conditions of the present
work, the increase in rate of pH decline after stunning at
480 and 600 Hz did not induce carcass and meat quality
defects. However, before any recommendation is given,
the influence of stunning frequency on turkey meat quality
needs to be evaluated under industrial conditions.