I trimmed a whole beef tenderloin last year by drawing on my memory of my father's advice and close supervision when he had a butcher shop. I got it done but swore I wouldn't do it again. But the Costco price was $12.99/Lb. whole or $20.99 trimmed. So—I bought two untrimmed tenderloins for our Christmas Day dinner party. (I'd prefer that you'd think of me as frugal, not cheap. You know—prudent fiscal management.)
One was 9 lbs. and the other was 7.8 lbs.
The Internet probably has several videos that explain how to do it. It's pretty easy but it's time consuming for those of us who rarely do it. But you need a sharp and pointed knife. A fish filet knife will work. When I say sharp, I mean
SHARP. As a youngster I quickly learned that I didn't want to be a butcher but I am daily grateful that my father insisted that I learn to sharpen a knife and keep it sharp. (Thanks dad.) If your knife isn't scalpel sharp you'll be pushing a dull knife and you'll have cramps before you finish.
So here's a short list of what you need to do to trim a beef loin.
1. At the thicker end there's a knob of muscle that should be removed.
2. Under the top side's layer of fat there's something called silver skin. It's about the consistency of a Gates fan belt and must be removed. Trim the fat off first, then work on the exposed silver skin.
3. There's another tube of muscle running the length of the tenderloin. It's called the chain and it needs to be removed, too. You can do most of the removal by pressing your fingers into the separation. It has some usable meet to be trimmed off and you'll see some more silver skin.
Here are the two tenderloins trimmed and one pile of salvaged small pieces for stew meat, stir fry and such.
Here they are tied with butcher's twine and rubbed with Penzey's Old World spice.
As near as I can tell I had three lbs. of edible trimmings. I don't know what the finished tenderloins weighed or how much weight was in the waste pile. I'll track it better the next time to see if it's really cost effective to trim my own. (It may have been worth it for the memories of working with my dad.)
They were wrapped in shrink wrap and placed in the refrigerator for a day and a half. I seared them in my Weber Kettle over a hot charcoal fire—all four sides for a minute each side and finished them on the indirect side. I pulled them at our desired temperature.* They made a fine meal.
I wanted to use T's M-3 but couldn't bring myself to gamble on meat for 14 guests.
*Tenderloins are somewhat tapered. As a result the thick end will be more rare than the thin end. Just have your guests bring their plate to the carving table and state their preference for thickness and doneness.
