The practice has sparked a row in Europe, particularly among Muslims, Jews and Hindus who observe religious bans on some animal meat.

The New Zealand Food Safety Authority said today it was aware of the practice but is "confident that this is not the case in New Zealand".

According to Xtra, it said the Poultry Industry Association had "assured NZFSA that only vegetable proteins are used by the industry".

"As we have no reason to suspect that non-avian animal proteins are in use we have no reason to carry out testing," said a spokesman for the food safety authority.

Michael Brooks, executive director of the Auckland-based Poultry Industry Association, told NZPA he had confirmed with local companies that they didn't copy the European practice of injecting animal proteins into chicken breasts.

"As companies here do not do it, there is no need for testing by the companies," he said.

Britain's Independent newspaper reported that cafes and restaurants across that country have been selling chicken secretly injected with beef and pork waste.

Food manufacturers are making bulking agents out of porcine and bovine gristle and bones that help inflate chicken breasts, so that they fetch a higher price.

The swindle was detected by the UK Food Standards Agency when it used new scientific techniques because the non-chicken material had been so highly processed it passed standard DNA tests.

UK laboratories developed special DNA tests to detect the highly-processed protein powders, and confirmed cattle collagen in some chicken breast products, and pig collagen in some of the powders.'

Jews are forbidden from eating pork as pigs are considered unclean animals, observant Hindus who eat meat almost always abstain from beef, and Muslims are prohibited from eating pork products.