How can I vacuum seal acidic ingredients with meat or poultry for freezing?

Home sealers don't like liquids in the bag, so use an ice tray to freeze any liquid you want to seal in the bag.

Both of these products freeze slushy, but that's fine. I squished the slush into a corner, and then added a layer of butter so that the chicken won't actually interact with the acidic ingredient until it's in the water bath. Just use the same temperature that you would for the same ingredients not frozen, but add 30-45 minutes of time.

I could make a freezer-full of these!

Alternatively, you can freeze your acidic ingredient and butter like this:

The butter will naturally rise to the top.

Now you could add your meat or poultry and seal if your vacuum is strong enough. Or you could add some chilled broth on top of the butter, add your meat and freeze vertically like this before sealing.

Of course you could easily tip the bag if you want the acidic ingredient in the corner.

You might want to make a sauce with your marinade and the juices in the bag. Scoop off some butter to saute your choice of aromatics, then add the defatted juices and reduce. You may want to strain it at that point. Thicken or finish with more butter, a bit of wine and/or some cornstarch or xanthan. See here: How should I prepare an excellent sauce from sous vide juices?