Sure, there was the flap over "pink slime"... but that was still beef, though it was washed in ammonia. I don't think it was the meat people were bitching about so much as the ammonia.
It should be noted that only one company produced the ammonia-soaked "pink slime", and they don't do it anymore. Other companies process trimmings, too, but they already used other methods to keep the meat bacteria-free.
Firstly, the meat is NOT "washed" or "soaked" in "ammonia".
"Ammonia/ammonium hydroxide is one of a number of processing aids used with meat and poultry in order to ensure the safety of these foods before they are delivered to consumers. The pH enhancement process is an important component of our overall food safety effort. By adding a tiny amount of ammonia (gas) to the beef, we raise the pH in the beef to help kill any harmful bacteria that could possibly be present."
They use ammonia GAS to raise the PH level so any bacteria are killed. This ammonia combines with the water present in meat to form some Ammonium hydroxide. "Ammonium hydroxide is naturally found in beef, other proteins, and virtually all foods. It is widely used in the processing of numerous foods, such as baked goods, cheeses, gelatins, chocolate, caramels, and puddings."
Second, if people were just bitching about the "ammonia", then they'd call it "Ammonia Meat", not "Pink Slime". The name "Pink Slime" is a biased term meant to evoke a negative emotional response rather then evoke a logical discussion. It's kinda like the sugar industry calling honey "bee barf", or the chocolate industry calling flowers "dead reproductive organs of plants" around Valentines day.
Third, it was produced by three companies, BPI, AFA Foods and Cargill. AFA filed for bankruptcy, Cargill significantly cut production, and BPI closed three of its four plants.
Fourth, as you (correctly) point out- "pink slime" was just... beef. It was little cuts and trimmings that, because it was attached to fat, were difficult to get. So, they heated it up to soften the fat, spun it to separate the denser meat from the less dense fat, then, just in case it had picked up any bacteria during this additional processing, they exposed it to ammonia gas. That's it.