Baking Soda and Vinegar with Green Food Coloring

I did a science experiment where I mixed baking soda with vinegar. You are probably familiar with this basic experiment of combining acid (vinegar) with alkaline (baking soda). However, I took it even further. I put in the baking soda in my experiment container (a basic jar) and then poured in vinegar. The I added baking soda, then vinegar again... etc. Every time I added the other ingredient the chemical reaction got noticably smaller.

I did another experiment whith the same unwashed glass... only I rinsed out the stuff inside. I put in the baking soda, and dropped in about 6 drops of green food coloring. I tried to mix it in with a spoon, but it wouldn't easily. I poured in the vinegar, and it fizzled and the green coloring concentrated and swirled around in interesting areas. I left it open for about a month. When I came back, the liquid had evaporated, there was the baking soda on the bottom, and on top of the baking soda, there was a broken green crust that looked like the land after a drought, but the cracks were so severe they were completely different pieces. When I poured vinegar onto the baking soda, there was no reaction. I have only one theory of how this could be: When the vinegar evaporated, it left the acid, which cancelled out the alkaline from the baking soda. So, in a sense, I had created baking soda with a neutral Ph! (like water)