1. Archive

THE FESTIVE FEAST // That perfect roast is all in the temperature

Browned and meaty yet pink and tangy. Crusty outside yet buttery inside. Firm yet tender. Juicy but not stringy. The art of roasting is the art of compromise.

It is one of the oldest forms of cookery, and it is one of the grandest.

The glorious roast beef is a popular candidate for Christmas dinner and other holiday feasts, especially for families who regard two turkeys in two months as too much. Yet, for most cooks, the roast is also one fraught with concern.

"We can learn to be cooks, but we must be born knowing how to roast," wrote the French culinary philosopher Brillat-Savarin in The Physiology of Taste in 1825.

That was before the invention of the instant-read thermometer. If it's a roaster you want to be, there can be no better way to spend $10 than to run down to the grocery store and pluck one off the housewares shelf.

Different from the traditional meat thermometer _ those notoriously inaccurate things that stay in the meat throughout the cooking process _ an instant-read thermometer gives you a quick and exact reading. Just plunge it into the roast at its thickest part (being careful to stay away from the bone), and within a minute you know where you are.

In roasting, temperature is all.

In a study called "Flavor, Color and Other Characteristics of Beef Longissimus Muscle Heated to Seven Internal Temperatures," agricultural scientists at Kansas State University found that "beef flavor components and juiciness change most from 130 degrees to 150 degrees, then little change takes place until meat is heated to temperatures between 175 and 185 degrees, when browned and mouth-filling blend components increase and juiciness decreases."

In other words, these guys roasted beef loin from very rare to very well-done. What they found was that the peak temperature for flavor and juiciness was between very rare and medium-rare (on the USDA scale), although the world at large is of course fiercely divided on the issue of the perfect temperature.

What it all comes down to is meat and heat. There are many things that happen when you cook a roast.

Flavor changes as cell walls break down, mingling amino acids and proteins.

Texture changes, from stringy and tough to firm and buttery and finally to dry and tough.

Juiciness (a function of both water in the meat and the saliva in the taster's mouth produced in reaction to the presence of fat) decreases as the water is squeezed from the meat fibers, and the fat is rendered.

Finally, and actually fairly unimportant to the cook, color changes (at least in beef and lamb) from red to brown. This is not, as one might suppose, because of the blood leaving the meat (in properly slaughtered meat, there is little blood left), but because of a molecular change in two related pigments called myoglobin and oxymyoglobin (pork, lacking these chemicals, is never red).

Here are some recipes for roast beef and some accompaniments.

Information from the Fort Worth Star-Telegram and St. Petersburg Times staff writer Chris Sherman was used in this report.