Composites calcium compounds and polysaccharides containing glucuronic acid.

Composite materials comprising calcium salts hardly soluble in water as nanoparticulate primary particles with an average particle diameter in the range of 10 to 150 nm which are soluble in water at 20 to less than 0.1 wt% and polysaccharides xanthan contain selected glucuronic acid, welan gum acacia and gum.