Am I the Asshole For telling people not to eat the food at my sister's wedding?

My husband (27m) and I (26f) were married eight months ago. We had a BIG wedding with lots of food and drinks and people. I knew we would likely have leftovers, so had arranged for them to be donated to the soup kitchen we sometimes work with, however, my mom went behind my back and took most of it with her. I didn't really know what happened to the food.

Until now.

My sister Callie (30f) got married over the long weekend. She didn't want to mess with any of the planning and- knowing how my mom was during my wedding- decided to let our mom take over the whole thing.

All we had to do was show up where we were told and party.

The ceremony was beautiful, but it was when the buffet was revealed that I noticed something odd.

The food looked eerily familiar. Like, identical to what I had for my wedding except for a little more dried out and sad.

I found an opening and went to ask my mom about it where she happily told me she "saved a fortune" by unfreezing the food from my wedding to serve to the guests now. I was horrified and immediately voiced my concerns about safety. She got upset and said I was acting like a snob and should be happy the food wasn't going to waste. I argued that it was never going to be wasted, but she wouldn't hear it.

I didn't want to make a scene, but was worried about people getting sick so snuck off to see my sister. She was horribly embarrassed- mentioned that mom said something about saving money but didn't question it because she didn't want to foot the bill like I had. She told me not to eat the food and thanked me for the warning.

From there, my husband and I discretely started telling some guests to be weary of the food and the rest of the night was fine.

My mom caught some flack for being cheap, but I've also been catching heat. Some of our relatives have been saying that I intentionally made my family look bad and that the food was fine as it was frozen and then defrosted for the wedding. They say no one would have known if I didn't make a stink over it. I don't know if I did anything wrong, I could use some help and would like to know if I should apologize. AITA?

EDIT: I'm getting a lot of repeat questions, so I figured I'd post here:

My wedding had about 200 guests. My husband has a large family and we intentionally planned for more people to come and knew that a lot wouldn't for one reason or another so knew we'd likely have leftovers and wanted to be smart about it.

My sister and her husband have been together for about 10 years. They recently decided to get married for tax reasons and wanted to do a courthouse wedding, but my mom BEGGED her to let her do an "event". So, she had a small wedding with only 50 people. My sister HATES planning and people, so she let my mom do everything

Have ya'll ever heard of garage freezers? They're super common where I'm from.