Roasting - Part IV
Perfect Roast Beef

Killing Trichinosis by Freezing
I mentioned in two of our discussions that the trichinosis parasite is killed at 137°Fahrenheit. As a result, pork should be cooked to 150°F to be safe. In response, one of our e-club members wrote telling us that freezing kills the trichinosis parasite. My brother, who is a physician, told me that about 15 years ago. However, he said the temperature had to be well below freezing. I decided to check up on that. This is what I found:

Trichinella spiralis, known as trichina, used to be a problem for pork in particular. The pigs were contaminated by eating infected rats or garbage. However, for over 20 years the feed of pigs has be carefully controlled, which at first involved the cooking of garbage to sanitize it, so that now trichinosis is very, very rare. Furthermore, freezing can kill trichina. However, as my brother related to me, the temperature has to be well below the freezing point, and for an extended period of time.

At 5° Fahrenheit, which is over 25° below freezing, for a piece of meat 6" or less, it takes 20 days to kill trichina.  For a piece of meat more than 6" thick but less than 27" thick, it takes 30 days. The colder the temperature, the less time required. At negative 10°F, for a piece of meat 6" or less, it takes 10 days to kill trichina; for a piece of meat more than 6" thick but less than 27" thick, it takes 20 days. At negative 20°F below zero, for a piece of meat 6" or less, it takes 6 days to kill trichina, for a piece of meat more than 6" thick but less than 27" thick, it takes 12 days. The typical chest freezer should hold food at about 0°.

       Temperature                   6" Thick or Less                6" Thick But Less
                                                                                         Than 27" Thick

      5° F                              20 days                                30 days
   -10° F                              10 days                                20 days
   -20° F                                6 days                                12 days

If you are going to count on freezing to kill trichina, check your freezer's temperature, and be sure to allow enough days for complete killing.

Perfect Roast Beef

My favorite beef roast is a boneless rib roast, known in restaurants as "prime rib." It is easy to do and wonderfully delicious. Finish it with some jus to top each piece when served. 

The technique I am going to describe will work for all the beef roasts typically cooked by dry heat: rib roast, top sirloin, rump roast, top round, and bottom round. In a future letter I will show you where each cut is taken from with photographs of examples.

Don't worry about having a heavy duty roasting pan. But do choose a pan that you can put over a burner and deglaze; i.e., add water or stock and loosen all the brown bits to make a jus or gravy. A stainless steel pan is ideal. I also like the Kaiser La Forme roasting pans; they have a magnum surface which is hard but stick resistant. Also, choose a pan that holds the roast with room to spare so you can pour in stock during roasting. Be sure to use a thermometer; it is the best way to know what is happening in the roast. More on that below.

The first thing you need to do is choose the method of roasting: slow, medium slow, and medium.

(1) Slow Roasting - heat is 200º Fahrenheit
(2) Medium-Slow Roasting - heat is 250º Fahrenheit
(3) Medium Roasting - heat is 300º to 325º Fahrenheit

Medium roasting is what most cookbooks recommend and for which they give time charts. Part of your decision will be based on how much time you have and part on the result you want. 

There are four primary temperature levels for doneness as follow:

(1) Rare - 130º Fahrenheit
(2) Medium Rare - 140º Fahrenheit
(3) Medium - 155º Fahrenheit
(4) Well Done - 160º Fahrenheit

First, time. A slow roast will take about twice as long as a medium roast. For a 4-6 pound roast, you can figure about 5 hours for a slow roast to get a medium rare result (140º at center); about 3.5 hours for the same result using a medium-slow roast.

Second, result. A slow roast permits the heat to gradually penetrate the roast so that the interior heats up fairly evenly. It will produce an interior of fairly uniform doneness. If cooking to medium rare (140º at center), the roast will have a firm but pink and juicy interior right up to the edges of the exterior surface. It is quite beautiful, and also moist, tender, and tasty. Also, that doneness makes excellent beef for roast beef sandwiches and French dip sandwiches. The beef is firm enough to cut easily, but also juicy and tender. If you have never slow roasted a beef roast, you should just so you can see the result.

However, some desire a center that is medium rare but the outer portion of the roast well done; they like the contrast in color, texture, and flavor between the soft inner meat and firmer outer meat. It also provides different degrees of doneness for the differing tastes of those eating. For that result, use a medium-slow or medium roast. At the higher temperature, the outer portion of the meat will heat up more rapidly than the inner and reach a higher temperature and greater doneness. You will have a roast with a well done outer portion and a medium rare or even rare interior, depending on when you stop the roasting process. The medium-slow roast will give you more medium rare meat in the center; the medium roast less.

I do not marinate, salt, or pepper the roast before I begin. I like a pure beef flavor, and I do not want extra salt in the jus or gravy. I will salt it to taste when I am done. With a rib roast, I make jus; with the others, I make a gravy using the low-fat method presented in my discussion last week.

Use the steps I presented in the last week's discussion. Be sure to take into account carry-over cooking; and leave time for the roast to rehydrate before carving, which was all discussed last week. Also, at the end of the roasting process, you will probably want to turn the oven up to 500º Fahrenheit for 10 minutes for final browning. When doing so, add some high quality beef stock to the bottom of the roasting pan to compensate for the evaporation of juices due to the high heat on the bottom of the roasting pan and to keep the brown bits from over cooking.

Third, the perfect instrument. There is an instrument that makes roasting to your desired point of doneness a breeze. It is the Polder Electronic Remote Thermometer-Timer, our item #2999. Its probe goes in the roast at the beginning of the roasting process, while the thermometer sits outside the oven. Insert the probe so the tip is at the dead center of the roast. Set the temperature for your desired doneness at the roast's center. As the roast cooks, note the time and doneness; regulate the heat up a little or down to bring the roast to perfect doneness at exactly the time you plan to eat. You will feel like a culinary pilot bringing your roast in for a perfect landing. One beautiful thing about the thermometer is that you do not have to open the oven at all during the process. You just look at it occasionally to see how the cooking is progressing. Of course, you do not need a remote thermometer; a classic meat thermometer or an instant read will do. I have those too, but they are not nearly as convenient.

Last Saturday I slow roasted a 4.4 pound boneless rib roast. I figured 5 hours of cooking time. I put the roast in the oven at 1:30 aiming at 6:30 for dinner, the roast done to medium rare (140º Fahrenheit). As the cooking progressed, I felt the roast would get done too soon, so I turned the temperature down to 190º Fahrenheit, later to 180º Fahrenheit; then later back up to 200º Fahrenheit. I finished it off at 6:15 by adding some beef stock and 10 minutes of browning, during which the oven was constantly heating to try to get to 500º Fahrenheit. The roast turned out perfect. I let it rest and rehydrate while Gail, the co-pilot, made jus. I served it a bit later than 6:30, but only minutes.