The boss of chicken supplier 2 Sisters has apologised to customers for doubts over food safety raised by a joint investigation by ITV News and the Guardian - but denied his factory had "low standards".
Chief executive Ranjit Singh Boparan told MPs he was "very disappointed and upset" by the undercover footage but insisted the factory produced "safe food".
"I can't accept we have low standards," he told the Environment, Food and Rural Affairs Committee. "I reassure you the food that we produce is safe."
Watch 2 sisters boss Ranjit Singh Boparan's full appearance (begins 30 minutes in)
2 Sisters is the second largest food company in the UK by sales and claims to process more than six million chickens every week.
Mr Singh Boparan said the firm's entire staff were being retrained in food safety and CCTV cameras extended as a result of the investigation as he pledged to improve safety standards.
"We've started a journey," he said. "This is a moment of change."
Mr Singh Boparan added: "We absolutely apologise for the doubt it's caused our customers."
Appearing alongside the firm's group technical director Chris Gilbert-Wood, he invited the MPs to come to the factory "announced or unannounced" to check on the safety procedures.
The men were accused by committee chairman Neil Parish MP of "being economical" after giving evidence over the alteration of kill dates.
Mr Singh Boparan said the changing of labels at the firm's Site D plant in West Bromwich was "not wrong" but accepted the footage suggested otherwise.
"It looks wrong, so it shouldn't be done," he said, but later added: "We do change labels, it's part of our process."
Mr Gilbert-Wood said the process of dating meat "wasn't as robust as it should be" and said "we have strengthened our system".
Regarding the sacking of a worker who was filmed changing kill date labels, both men denied the dismissal was related to his part in the investigation.
"We've never fired anyone who is a whistleblower," Mr Singh Boparan said.
Mr Gilbert-Wood said the worker had "denied he was in the footage" and added that another worker filmed admitted his role and has kept his job and undergone retraining.
Although the factory had 36 CCTV cameras capturing 24-hour footage, the men confirmed the system had largely failed to capture the incidents in the undercover filming.
"Sadly, the CCTV footage doesn't cover the complete factory," Mr Gilbert-Wood said.
Mr Singh Boparan said the firm was extending the CCTV to cover "every aspect" of the factory and all of its other factories.
"If there is something we can learn from this, we will put it right and move on from this," he said.
ITV News reached out to UK supermarkets in regard to Mr Singh Boparan's appearance in front of MPs.
A Sainsbury's spokesperson said: "We were concerned by the allegations and stopped taking products from the site. We're watching the committee hearing very closely."
A spokesperson for Lidl UK said: "We remain in close communication with both 2 Sisters and industry partners on this matter and await to hear the committee’s conclusions and recommendations."
ITV News also contacted Marks & Spencer, Aldi and Tesco and is awaiting a response.
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