There are a couple of different ways you can identify a base. 

One is by counting the hydrogen ions on each substance before and after the reaction. If the number of hydrogens has increased after the reaction, that substance is a base (bases accept hydrogen ions hence the increase). 

Another way to identify a base is by dipping a red and a blue litmus paper into the substance. The substance is a base if the red litmus paper turns blue but there is no color change with the blue litmus paper.