miss flavored mop

[LT72884]

I made my first mop today. it tasted AWESOME until the last two ingredients.

I added three lemon slices and 1 tbls of butter.

here is the actual recipe i made up

1.5 cups distilled or cider vingar(most say distilled white tastes best)
1/8th cup or less ground pepper
1tbls or less crushed red pepper
1/4th cup ketchup
1/4th cup kosher salt
dark brown sugar. enough to balance the salt and vinegar flavors
chili powder
minced onions
lemon slices
butter

My wife told me it could be the butter. i agree. maybe the fat and the acid had a fight and the fat lost. haha

i know its one of those two ingredients. My question is... WHY? haha

and how to fix it with out making it worse.

thanks