Researchers at Tohoku University in Sendai, Japan have developed a new type of “super silk” by modifying the diet of silkworms. This was done to prevent silk from shrinking and losing its shape when exposed to moisture.

The researchers added plant-based cellulose nanofibers to the silkworms’ food. This simple change resulted in silk fibers with 50% higher tensile strength than conventional silk. The modified silk also showed significantly better resistance to shrinking, with the fibers shrinking to less than one-quarter of the amount seen in regular silk. These improvements remained consistent even after the fibers were spun into yarn and made into textile fabrics.

“Our goal was to improve silk while preserving its natural advantages,” said Hiroki Kurita, Associate Professor at Tohoku University. He explained that the team was pleased to discover that a simple change in the silkworms’ diet produced silk that is both stronger and much more stable in wet conditions. Kurita added that the researchers hope this sustainable approach will support the development of next-generation functional textiles.