Here are instructions on how to open it, from Apple.
"Wait, instructions?"
Yeah...Food Sage is an "unsigned app", meaning I haven't paid Apple $99/year to certify it. So, when you try to open it, you'll get some scary warnings. To get past them, you have to tell macOS that you know what you're doing and you're super-duper-sure it's safe.
It technically could be a virus...but it's not! You have my word.
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