not a doctor but a "one off face swelling" after eating something for the first time seems like it would be much more rare than an actual allergic reaction.
That's what I thought too, until I had a one off face swelling and throat closing event after eating a new food and went to an allergist, only to learn I was not allergic and have had successful re-eatings of that food.
What I learned from the allergist is, histamine angioedema is essentially the same thing as anaphylaxis, and is treated the same, but is different in cause in that repeat exposure to the food item will not cause a repeat episode.
I'm not a doctor either, but according to my allergist (who is), most people who think they are allergic to some random thing that most people have never heard of people being allergic to, are not in fact allergic to that thing.
Reading the full text of the article you linked it looks like their criteria cover both angioedema and anaphylaxis and add the two together.
> The most common triggers reported were medications (34%), foods (31%), and insect stings (20%)
https://pubmed.ncbi.nlm.nih.gov/24144575/
not a doctor but a "one off face swelling" after eating something for the first time seems like it would be much more rare than an actual allergic reaction.