Turkey Meat. Seasonal Effect on Meat Quality and on Dead on Arrival Index in a Commercial Plant

ABSTRACT The objective of this study was to determine the incidence of Pale, Soft, Exudative (PSE) meat and to characterize the Dark, Fim, Dry (DFD) meat as well as the Dead on Arrival (DOA) index in a commercial turkey slaughterhouse in southern Brazil during the summer and winter seasons. The journeys (n=64) were over a distance of 36 ± 20 km and took approximately 95 ± 20 min. Color (L*) and pH distribution of turkey breast meat (n=5,352) were evaluated from different farms (n=64) during the 2015-2016 years. The pH, water-holding capacity, color (L*, a*, b*) were used to establish cutoff values for DFD meat (L* < 44.0 and pH > 5.90) and presented correlation among them. The L* value was the highest during the summer (P<0.01), indicating the highest incidence of PSE meat (28.35 %), and lowest during winter, observing the highest incidence of DFD meat (10.3 %). Finally, the obtained summer DOA index was 0.23 % higher in relation to winter.

Commercial preslaughter blue light ambience for controlling broiler stress and meat qualities

The objective of this work was to study the effect of blue light diffuser on the broiler stress control by measuring the occurrence of PSE meat just before slaughtering. Birds were divided into the following two groups before slaughter at the point of being hung on shackles: broiler group under low intensity blue light ambience (475, 17-20 lx) and control group under white light (550-650nm, 321-332 lx). Birds' stressful conditions were measured by the occurrence of PSE meat. Breast fillets were classified as PSE meat based on pH (<5.8) and lightness (L*> 53.0). The fillet samples in the control group had the following characteristics: pHu=5.77, L* = 54.26 and b*= 6.27. The fillet samples from birds under blue light ambience had the following characteristics: pHu=5.81, L* = 52.86 and b* = 5.22 (p < 0.05). These results revealed that the treatment of blue light ambience just before slaughtering contributed to the alleviation of ante mortem stress of the birds, which was observed by a 14% decrease in the occurrence of PSE meat. Exposure to blue light just before slaughtering was shown to have potential to be used in modern slaughterhouses to offer a comfortable atmosphere, thereby maintaining breast meat quality.

Lipid oxidation and fatty acid profile related to broiler breast meat color abnormalities

The aim of this work was to study the influence of lipid oxidation on broiler breast meat (Pectoralis major m) color abnormalities. There were 27.0 percent more lipid oxidation in PSE in relation to normal meat and 41.0 percent more in relation to DFD-like meat (p<0.05). The fatty acid profile was also significantly different since the arachidonic acid (AA) fraction increased 38.6 and 70.5 percent in PSE meat comparing to normal and DFD-like meats, respectively. The ratio PUFA/SFA changed in these three types of meat: 0.736, 0.713 and 0.694 for PSE, normal and DFD-like meat respectively, reflecting the highest production of polyunsaturated fatty acids in the PSE meat samples. Results indicated that phospholipase A2 enzyme activities played a relevant role towards the development of PSE-meat syndrome in a cascade of biochemical reactions promoting the formation of free radicals from AA, which ultimately damaged the muscle membrane systems.

A influência da oxidação lipídica no surgimento das anormalidades das cores do filé do peito de frango (Pectoralis major) foi avaliado. A oxidação lipídica foi 27 por cento maior em carnes PSE em relação ao normal e 41,0 por cento em relação ao análogo DFD (p< 0.05). O perfil dos ácidos graxos foi também significantemente diferente desde que a fração do ácido araquidônico (AA) aumentou 38,6 por cento e 70,5 por cento em carnes PSE em comparação às carnes normais e análogas ao DFD, respectivamente. A razão PUFA/SFA se alterou nos três tipos de carne, 0,736, 0,713 e 0,694 para carnes PSE, normal e análogo ao DFD, respectivamente, refletindo a maior produção dos ácidos graxos polinsaturados em amostras PSE. Esses resultados corroboram os nossos anteriores, indicando que a atividade da enzima fosfolipase A2 tem um papel relevante no desenvolvimento da síndrome do PSE em uma cascata de reações bioquímicas promovendo a formação dos compostos radicais livres do AA que finalmente compromete os sistemas das membranas celulares do músculo.

The effect of management of transport and lairage conditions on broiler chicken breast meat quality and DOA (Death on Arrival)

The aim of this work was to evaluate the influence of time of broiler chicken transportation and lairage prior to slaughtering on the occurrence of PSE (Pale, Soft, Exudative) meat and Death On Arrival (DOA) under non-commercial conditions in the Brazilian summer. Male birds (n=250) from a commercial line were subjected to different periods of journey (30, 90, and 180 min) and lairage (0, 90, and 180 min) before slaughtering. The occurrence of PSE was higher in broilers subjected to shorter journeys and lairage periods, whereas DOA was more pronounced upon longer periods of transport and lairage. The DOA occurrence percentage was much higher in comparison to commercially available figures, confirming that broiler chickens are very sensitive to both transport and lairage maneuvers.

O objetivo desse trabalho foi avaliar a influência do tempo de transporte e período de descanso antes do abate dos frangos na ocorrência das carnes PSE (Pale, Soft, Exudative: Pálido, Amolecido e Exsudativo) e DOA (Dead On Arrival: Morte Na Chegada) nas condições não comerciais durante o verão brasileiro. Frangos machos (n=250) de uma linhagem comercial foram submetidos a diferentes periodos de jornada (30, 90 e 180 min) e descanso (0, 90 e 180 min) antes do abate. A ocorrência do PSE foi maior em frangos submetidos tanto em tempos para as viagens curtas como para o de descanso enquanto que DOA foi mais pronunciada em condições de jornadas longas e maior periodo de descanso. A porcentagem da ocorrência do DOA foi maior ao se comparar com os resultados obtidas por empresas comerciais confirmando que os frangos são sensiveis às condições das viagens e de descanso a que são submetidos.