When mine started to be noticeable, I had what I could call a fluttering feeling in my chest. That said, I thought it was my heart. It wasn't. It turned out to be a hiatal hernia, esophagitis, and GERD. Three endoscopies revealed Barrett's esophagus.
I'm not familiar with the Alkaline Diet, but I was told to avoid chocolate, tomatoes, citrus fruits, fatty foods, peppermint, and stuff like that because they tend to aggravate things more.
I hope this helps a little.