By Dylan Clay
The full loin primal is taken from the hindquarter of the beef carcass.
The loin is home to some of the best cuts on the entire animal.
This cut is so loved that if you were to order a side of beef from a Farmer/Butcher, you’d find yourself struggling to pick the front-quarter or hindquarter solely due to this section of the animal.
It is cut from the round primal at the ball and socket joint where the femur meets the hip.
It is also separated from the rib primal at the 12th/13th rib.
There are 4 sub-primals found in the loin primal:
From a naming perspective, these sub-primals and their associated retail cuts are often the most confusing on the entire animal.
The short loin sub-primal is taken from the front part of the loin.
This portion runs from the 13th rib (where the beef rib is removed) all the way to the last lumbar vertebrae.
Popular cuts from the short loin include:
The tenderloin is comprised of three muscles – the psoas major, psoas minor, and iliacus.
In terms of anatomical location, it sits inside the short loin and extends along the cow’s pelvic girdle and along the spinal column.
If we were to look from the rear of the cow, the muscles look like this:
The tenderloin itself also tapers from being small (towards the front of the short loin) to large towards the back (towards the sirloin).
Towards the front of the muscle is where “filet mignon” comes from (quite literally 1-2 steaks) as this is the most tender part of the cow.
When left bone-in, this muscle is what differentiates t-bone steaks from porterhouse steaks; As the USDA has specific criteria for the width of the tenderloin.
From the above we can see how the “t-shaped” bone is formed.
The void semi-circle is the vertebral foramen; The “center-line” of the T is the transverse process of the vertebra.
The strip loin is the other half of the short loin – opposite the tenderloin.
The primary muscle that comprises the strip loin is the longissimus dorsi (the same muscle that makes up the “eye” of a ribeye steak).
However, other muscles do make up the strip loin, including the multifidus dorsi and the gluteus medius (found near the end of the strip – this muscle makes up the sirloin).
The strip loin can go by a few different names:
From this sub-primal we get top sirloin butt and bottom sirloin butt.
The top sirloin sits just under the tenderloin. Where-as the bottom sirloin sits right under the top sirloin.
From the top sirloin you get steaks like:
From the bottom sirloin you get cuts like:
The loin itself contains some of the most popular cuts on the entire cow, namely:
Other cuts (some deem offal) that come from this section include:
*This suet actually engulfs the tenderloin. Butchers will tend to be rather careful with their cuts so as not to slice into the tenderloin.