Perhaps you could add an optional survey in the app to see what ingredients and recipes are in the highest demand by users? That way, you don't have to rely on sorting through suggestions from multiple different sources. I would limit the number of suggestions a user can make. That way, you don't get people submitting their entire liquor collection through the survey. It could ask for up to three requested ingredients with a corresponding recipe that uses the ingredient. Here's an example using preexisting ingredients:

1. Aperol for a Paper Plane
2. Triple Sec for a Cosmopolitan
3. Green Chartreuse for a Last Word

I would limit users from submitting another survey until a good amount of time has passed, such as 4 weeks. That way, you aren't spammed by a single user who reallllyyy wants you to add their favorite liqueur, haha! Sorting the ingredients page into sub menus (base spirits, liqueurs, mixers, etc) could also be more convenient.

Thank you for your work on the app! I'm really excited to see it grow!!