I have heard that you can get the fattiest type, drain the grease as normal, and then rinse the meat with water in a colander to make it equivalent to the extra lean fat content. I'm not sure I buy that, and it seems this would rinse off any seasonings used also.
That sounds terrible. Cooked ground beef should be drained if necessary, but not rinsed. It will rinse away a lot of flavor, and I doubt it makes it the equivalent of having bought lean meat in the first place. There is still plenty of fat present in the meat itself.
If you want low fat get extra lean. If you want flavor get 80/20 or 70/30 and drain thoroughly for as little fat as possible. Do yourself a favor though and don't rinse it with water.
Your filling is basically a beef stew/casserole, so any cuts that suite long slow cooking are fine. They get cooked again while the pie is baked, so premium cuts will just be wasted
The lower grade and 'off cut' parts are what are most commonly used. Like rump, brisket, chuck, shank, neck etc
Using a bench top slow cooker makes cooking this all very easy. The beef needs to be fully cooked before making the pie. An eight hour slow cook is fine
You want the pieces to be a variety of sizes to fill out the pie shape, but make sure you have some at least the height of the pie filling. The larger pieces tend to be better, but that could be a matter of taste and culture
You need to get rid of plenty of fat before and after cooking. A mouth full of fat in a pie is not nice. There is already plenty of fat in the gravy and pastry, so trim off all you can
A good meat pie should have a solid layer of meat connected with gravy, not swimming. It should also not be so full as you can't eat it with your hands (for a single serve pie) without loosing half the contents
Puff/flakey pastry works best and holds everything together
Avoid overly strong flavoured gravies, you don't want to hide the beef and pastry taste
Before you attach the lid, place a slice of tasty cheese, or an extra generous serving of cracked pepper on top of the filling
A respectable pie looks like this - thanks to Ponsonby Pies (not made in Ponsonby anymore)
Best Answer
Molecular biologist here - there's no simple or cheap way to do this at home. You could try approaching your local university and see if they would be interested in testing samples for you - food adulteration is a big issue.
There's also the possibility that you are allergic to the turkey as well. The American College for Allergy, Asthma and Immunology suggest that this is entirely possible. If you have one meat allergy you are more likely to have another. Having said that, if what you have is actually an alpha-gal allergy (e.g. as a result of a Lone-star tick bite), these are only found in mammalian meat, birds (like turkey) have no alpha-gal, so a reaction to turkey would likely indicate cross-contamination.