Sourdough with lemon juice

Have been trying to make sourdough with at least 1/3 wholemeal flour, home grind from grains, but bread texture becomes too rough and does not rise well, not enough gluten in the mix..
Read in a French magazine that in Traditional Baguette, baker can use flour, salt, yeast plus only one chemical, citric acid. Whereas in other types of bread, they can use up to 12 chemicals to improve performance. 

Turns out that lemon juice/citric acid can improves elasticity of gluten, helps to make bread rise much better.
Immediately added some lemon juice of in my sourdough mix, and indeed notice the difference in kneading, and rise of the dough improves. On top, the texture of resulting bread is more homogenous and smooth than before!