I am not a professional, but for the last few years I consider cooking to be by far my primary hobby. I am also a very technical/science minded person, so your mileage may vary:
+1 - On Food and Cooking
+1 - The Professional Chef (I got my 8th edition copy for $10 at a used book store)
Someone mentioned "Charcuterie" by Polycn/Rhulman. I branched into charcuterie myself about 2 years ago, and that was my starting point. However, after picking up a few others, my recommendation on the topic would be "In The Charcuterie" by Toponia Miller and Taylor Boetticher. For the best science oriented (plus many good recipes...just no fancy pictures) option I would recommend "Home Production of Quality Meats And Sausages" by Stanley Marianski & Adam Marianski.
For Japanese cooking, there is nothing that even compares to Washoku and Kansha (both by Elizabeth Andoh). This is my current obsession...probably because I just got back from Japan where I took a 3 day intensive cooking class run by Mrs. Andoh. My first actual class experience (otherwise completely self taught to date), and it's REALLY upped my game in Japanese cooking.
The only other thing I'll add, is that I've found a lot of success focusing on a specific dish and searching good blogs and youtube videos to see how other people have written about it and presented it. After a few years of doing this, I've found that I can quickly identify something that will work for me when searching out something new, and there's a good dozen or so blogs that I can really rely on (No Recipes, Smitten Kitchen, Frugal Gourmet, Cured Meats, etc). It's all about finding sources that you can easily relate to and absorb information from.
GOOD LUCK!