Adding A New Parameter To Notification Products Table

Hello everyone,

We're developing an add-on for our customer and we encountered a problem.
In database, in table order_details we added a new column. We'd like to include value from this column in e-mail notifications, in products table, so for each product in order, a respective value from this column should appear.

We figured out how to do this by editing source code (change file app//Tygh/Template/Snippet/Table/ProductVariable.php), but we don't know how to do this using hooks. Has anyone tried to do something like that and managed to find a solution that does not require modifying core?