When in Rome, do as the Romans do! The same is with labelling food. For my international readers it might be interesting how to label a bread with grains in Germany. If you say grain relating to bread it always means cereal grain, fruit of grass. The German Guidelines of Bread and Pastry are very strict. Typical cereal grains are wheat, rye, spelt, buckwheat, barley, oat, millet/sorghum, maize/corn, rice and tricitale. Although buckwheat is not a grass, but a member of family Polygonaceae, it counts as a cereal grain in Germany. Pseudocereals like amaranth or quinoa don’t count as a cereal grain.
With a German view the recipe from p. 238 of Bread: A Baker’s Book of Techniques and Recipes
Five Grain Bread
A nice bread, but instead of getting more flavour with a bulk fermentation over night, I prefer a sourdough version.
The bread has a hydration of 90 %, sometimes a bit tricky for my flours. I made a hot soaker and it worked fine.
It tasted great with a rum flavoured Mettwurst from Schleswig-Holstein