They're using rice flour but processing it in a way that gives it the consistency, the 'bubble structure' and the volume of standard bread. Although there are a few gluten-free options already available, the mass-produced loaves often don't give the person the same experience of eating regular bread.
Wheat bread forms a flexible matrix that allows it to rise in the fermenting phase, but because rice flour doesn't have this, the gluten-free loaf has never been able to emulate the same consistency or feel.
Researchers at Hiroshima University in Japan analysed the make-up of wheat flour to discover that it contains bubbles that are coated in undamaged starch particles in a 'stone wall' arrangement that aren't in rice flour. These bubbles stop wheat bread from collapsing in the baking process.
But by processing rice flour differently, the researchers—who work for Japan's National Agriculture and Food Research Organization (NARO)—have successfully replicated the texture and taste of the wheat loaf, and without using gluten.