These Stella McCartney Knitwear Pieces Are Made From Fermented Proteins

PETA activists are calling for an end to the use of wool. Stella McCartney, meanwhile, has brought a series of knitwear pieces to the runway made with a yarn that has more in common with yoghurt than with a sheep.

Called Brewed Protein, the fibre is produced through microbial precision fermentation, meaning it is made without animal-derived materials. It is developed by Spiber, a Japanese biotechnology company that creates synthetic textile fibres with a fineness comparable to that of baby cashmere.

From an environmental perspective, the production process for Brewed Protein has the potential to reduce greenhouse gas emissions by approximately 75% and water and land use by at least 90% compared with conventional cashmere.

For this collection, Stella McCartney created a series of fisherman knits, the classic ribbed sweaters inspired by those traditionally worn by fishermen. The designer is known for pushing the boundaries of material innovation. Over the years, the prominent environmental advocate has brought numerous innovations to the runway, from plant-based sequins and non-animal-derived faux feathers to a wide range of alternatives to animal leather.