I have long wondered why all of the canning texts exhort one to use a plastic or wooden utensil to remove air bubbles before processing. I've read that it's because you want to avoid scratching the sides of the jar. But when you're digging out the last of the jelly with the butter knife, doesn't it make that a moot point? If there is another reason to use plastic, I'd like to know.
PS: This question comes about because I used a knife to remove air bubbles when I canned my apple butter. Am I going to die?