Meat-alternative start-up Impossible Foods has put more flesh on the bones on when it plans to launch its burger into the US retail channel as it revealed a regulatory boost for a key ingredient.

The California-based business, which also today (31 July) announced a manufacturing deal with a major player in the meat industry, said it plans to launch the Impossible Burger into its domestic retail market in September.

The burger made its debut in select restaurants in 2016 and is now on sale in around 10,000 outlets in the US, Hong Kong, Singapore and Macau.

Meanwhile, Impossible Foods said the US Food and Drug Administration had cleared the use of soy leghemoglobin as a colour additive.

The regulator had approved soy leghemoglobin as a “generally recognised as safe”, or GRAS, ingredient last year. Impossible Foods then launched a separate move to get the green light to use the ingredient as a colour additive.

“We’ve been engaging with the FDA for half a decade to ensure that we are completely compliant with all food-safety regulations—for the Impossible Burger and for future products and sales channels,” Impossible Foods chief legal officer Dana Wagner said.

Meat giant OSI Group is to manufacture the Impossible Burger for the plant-based business. Impossible Foods already makes the product at its facility in Oakland, California.