Water baths are commonly used to stun poultry for the halal market. But these present many potential problems for the bird, businesses and halal consumers, according to Steve Wotton, senior lecturer in Food Animal Science at the University of Bristol.
Because of the high volume of birds passing through the water baths, it was difficult to deliver a consistent current of 100 milliamps, which was needed to stun the bird, he told a Halal Food Authority seminar in London recently.
“As a result, some birds will get too much [current] and at the other end of the scale, some birds may not be getting stunned at all,” he said.
Birds stunned in a water bath were also more likely to flap their wings, potentially damaging them and devaluing the carcase as a result, Wotton added.
However, the Dutch-based machinery manufacturer TopKip had developed a head-only stunning line, which delivered a consistent current to ensure each bird was stunned, he claimed.
“The Dutch system takes the birds on a processing line, applies plates to the head of each bird and applies a consistent current,” Wotton explained.
Birds were also placed in a cone to prevent their wings from flapping at the time the current was applied, he added. The cone also reduced the amount of time birds spent inverted on the line, which was painful for them, he claimed.
“Chickens don’t have a strong vertebrae system and inverting them puts them through a lot of pain,” he added. “This [TopKip] system is taking the possibility of [high and humane output] halal poultry slaughter further.”
TopKip has one operational line in Canada and more would be rolled out later this year, it said.
Almost 1bn chickens are slaughtered in the UK each year, of which 31% are for the halal market, according to the Food Standards Agency. The vast majority of halal meat is stunned before slaughter, other figures have suggested. The halal meat industry is estimated to be worth £2.6bn a year.
To be halal, animals are required to be alive at the time of slaughter, which is why halal poultry is often stunned instead of gassed. A prayer is also said before a knife is used to kill the bird by cutting its throat.
Gassing is a method widely used to kill poultry in non-religious slaughter, because it is believed to be more humane and efficient.