Yesterday I tried making a meringue-based dessert with a recipe I've used successfully a few times before, which calls for 6 egg whites and 1.5 cups of sugar. I made sure to have no egg yolk with the whites, I used a stainless steel bowl and mixer attachment, the eggs were at room temperature - everything to my knowledge that should result in perfect peaks after mixing thoroughly.
After getting everything together though, my first batch of meringue never got past a marshmallow fluff-like thick but somewhat runny consistency. I tried again two more times being very careful to make sure everything was perfectly clean, and ended up with the same results each time.
At this point while cleaning up, I notice the packaging for the eggs stating that they have "25% less saturated fat than regular eggs" eggs, due to a special diet.
Could lower than average fat content in eggs affect getting stiff peaks from a meringue?