Tenderloin, prized for its tenderness, is an expensive cut of beef. A tenderloin tapers towards one end, and the ‘tip’ of the tenderloin is not suitable for tournedos or châteaubriand. Tenderloin tips are therefore available at about half the regular price of beef tenderloin. Other than their shape and size, their taste is exactly the same!

I’ve written before about transglutaminase, a natural enzyme that is sold under the brand name of Activa. The enzyme allows you to ‘glue’ meat, thus turning tenderloin tips into a tournedos! The enzyme doesn’t come cheap, but you only need a little (less than a dollar’s worth to glue a kilo/2 lbs).

Transglutaminase comes in a powder that you can either sprinkle directly onto the meat, or that you can mix with cold water in a 1:4 ratio to create a slurry. The latter is easier to apply more evenly and works better on an uneven surface. In Activa RM (in the US)/Activa EB (in Europe) the enzyme is mixed with a helper protein to make it glue even more effectively. Although it may sound ‘chemical’ to glue meat, it is a natural ingredient and if you keep to the dosage of 1% you won’t be able to taste it.

With help of transglutaminase, we can turn those cheap tenderloin tips into a prized tournedos!Or to prepare a wonderful Rosa di Parma at half the cost. Here’s how…

Weigh the tenderloin tips and calculate 1% for the amount of Activa to be used (e.g. 10 grams for 1 kilogram or .35 oz for 2.2 lbs). Wash the tenderloin tips under cold running water and pat them dry with paper towels. Combine the tenderloin tips with the Activa in a bowl…

…and toss to coat the meat evenly with the powder. The glue will hold slightly better when you make a slurry first by combining the Activa with water in a 1 : 4 ratio (so 40 ml of water for 10 grams of Activa), but that does mean adding 4% of water to your tournedos.

Arrange the tenderloin tips in a metal ring of the appropriate size, pushing down thoroughly to avoid air pockets.

Vacuum seal the meat with the ring to eliminate all the air. Now you can either allow the enzymes to do their job in the refrigerator, which will take at least 6 hours for the meat to bind well.

Or you can cook the meat sous-vide, where the higher temperatures (which must however be less than 58ºC/136ºF as otherwise the enzymes would break down before they can bind the meat — but who would want to cook tenderloin to such a high temperature) will make the enzymes work much faster (5 minutes at 55ºC/131ºF).

I prefer tenderloin to be only ‘warm aged’ at 50ºC/122ºF for 2 hours. There is some risk in this, as this temperature may not destroy all pathogens that could be present on the surface of the tenderloin tips. That is why washing the meat and working with clean hands and clean utensils is important. If you are going to serve the tenderloin to someone with a fragile health, cook to at least 55ºC/131ºF (this is actually also a good idea when using regular tenderloin instead of glued tenderloin) and long enough to pasteurize the meat.

The meat will release a minimal amount of juices that can be discarded as it is too little to make a sauce.

Use a knife if needed to release the constructed tournedos from the metal ring.

Dry the tournedos carefully on all sides with paper towels. Dry meat will ensure better browning.

Brown the meat in a very hot frying pan with clarified butter for about two minutes per side, then allow to rest for 5-10 minutes.

The result is a wonderfully rare/medium rare tournedos. You can hardly tell that it has been glued together from tenderloin tips.

I also tried to prepare one of my favorite dishes with tenderloin tips, Rosa di Parma. This is beef tenderloin stuffed with prosciutto, parmigiano, rosemary, and garlic. When sliced, it looks like roses. Again the tenderloin tips with transglutaminase worked very well, and in this recipe you notice even less that tenderloin tips have been used instead of regular tenderloin. So it is great way to save money on this delicious impressive dish.

Start by pounding the tenderloin tips to an even thickness of about 1 cm (1/3 inch) between two sheets of plastic wrap.

Wash the tenderloin pieces and pat them dry with paper towels.

Arrange the pieces into a rectangular shape as best as you can.

Mix the Activa (again 1 gram of Activa for each 100 grams of beef) with cold water (4 ml of water for each 100 grams of beef). Paint the meat with this slurry, painting in between the pieces as well.

Put slices of prosciutto on top. Since the beef only has limited surface to bind together, most of the binding will be between the beef and the prosciutto.

Carefully tranfer the beef to a vacuum pouch.

I used two sheets of kitchen paper to help with this operation. Remove the sheets, then vacuum seal.

Refrigerate for 6 hours for the beef and prosciutto to bond.

Season the beef side with salt and freshly ground black pepper. Brush the prosciutto side with a mixture of garlic, olive oil, and rosemary and sprinkle with freshly grated parmigiano as per the original recipe for Rosa di Parma.

If you don’t have sous-vide equipment, you can now roll up the meat, tie it with kitchen twine, sear it in a frying pan, and finish it in the oven (see the post on Rosa di Parma for details).

To cook sous-vide instead, roll it up and vacuum seal.

Cook sous-vide for 3 hours at 54ºC/129ºF.

Pat the meat dry with paper towels and very quickly sear it in olive oil over high heat. (See the original post on Rosa di Parma for details on making a sauce.)

Serve on preheated plates.

Flashback

Ragù Napoletano is a traditional dish from Naples, Italy that is mostly eaten on Sundays. Large pieces of beef and pork are cooked low and slow in a tomato sauce, and then the meat-flavored tomato sauce is served over pasta as the primo piatto, followed by the meat with a bit of the sauce as the secondo piatto.