On the right is a loaf made from grain grown in today's climate conditions. On the left is a loaf made from grain that sprouted in concentrations of carbon dioxide that are expected by mid-century if greenhouse gas emissions aren't reduced significantly.

So this is 2050 bread. It was baked at the Australian Grains Free Air CO₂ Enrichment facility (AgFace) in Victoria by a research group studying the effect elevated carbon dioxide will have on crops such as wheat, lentils, canola and field pea.

AgFace leader Glenn Fitzgerald said the effect of high carbon dioxide on grains is complex. On the one hand, it makes plants such as wheat and canola grow faster and produce greater yields but, on the other hand, they contain less protein. Elevated carbon dioxide also alters the ratio of different types of proteins in wheat, which, in the case of bread, affects the elasticity of dough and how well a loaf rises.

"We don't understand completely why that's the case," said Dr Fitzgerald, a senior research scientist with the Department of Economic Development, Jobs, Transport and Resources.

The group is now conducting research to see whether it can reverse the protein decline through the selection of new varieties of wheat. Grain breeders might then be able to develop new wheat strains with traits that can overcome this problem.