Can changing food cause dog to vomit?

Hello all! I have recently started to slowly switch my 1 year old dog from medi-cal food to Eagle Pack. I have been doing this VERY gradually. At first, she was eating about 80% old: 20% new. She ate it up no problem...but after about 20-30 minutes, she vomited a bit. She ate that right back up (eeuuw!) and then was fine. No problems for the rest of that day or the days that followed. She was on that ratio for about 3 days and was fine all the other days. Today, I switched to 70% old and 30% new. It was only a difference of 50ml to 75 ml of the new food so not a huge change. She again vomited about 20 min later and is now fine. Could this be just her reacting to the new "holistic" food? Is this just a coincidence? She does seem to get used to the food so do I keep going or should I try a different brand already?

Could she be eating the eagle pack faster? Dogs can vomit like that (i.e. right after eating) when they eat too fast. Maybe the first day, she eats faster and then the second, takes a breather.

It's all mixed in together but I guess she could be digging it out. She certainly is more enthusiastic about eating since we've switched. She would always eat before but now it's like she can't wait for me to set the bowl down! I haven't noticed if it's only after she eats in the morning that she does it. But that coudl be it. Maybe it's just the 'Excitement"! :)