They were stored locally on your Macbook in the Documents/BeerSmith3 directory (or BeerSmith2 directory if you used that version). The file is Recipe.bsmx if you can recover it somehow from your old hard drive.
Here's an article on working with BSMX files:
http://beersmith.com/blog/2019/01/27/sharing-beer-brewing-data-using-bsmx-files-in-beersmith/
Brad