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suits to date indicate t h a t there is a relation between rate of growth, as controlled by level of feeding and palatability of the cooked meat.

COOPERATIVE MEAT INVESTIGATIONS SUMMARY OF RESULTS OF COOKING MEATS LUCY M. ALEXANDER

U. S. Department o/ Agriculture Seven years ago a report was presented to this society on the newly organized national project "A Study of Factors Which Influence the Quality and Palatability of Meat" (later "Cooperative Meat Investigations"). In t h a t report cooking was named as a phase of the project. This marked a new era in the study of m e a t production. Through years and years of experimentation prior to the organization of the national meat project livestock studies had ended with the slaughter of the animal. Now production practices are being put to the "table t e s t " and it is possible to measure results in t e r m s of probable consumer satisfaction. The added value t h a t this test contributes to production studies is undoubtedly worth m a n y times w h a t it costs. At the same time the new project on meat has opened to home economists a field of far-reaching possibilities in experimental cookery. That some progress has been made in this field is shown by your president's request for a s u m m a r y of our accomplishments to be presented to you at this time.

Standard Methods Necessary When called upon to cook cuts from animals of known history, the first task was to work out a standard method of preparation. For beef ribs the foundation had already been laid by the Illinois station where experiments carried out about the year 1900 had shown the advantages of roasting this cut in an open pan without water. They found t h a t uniform cooking with small shrinkage resulted from the use of a high oven t e m p e r a t u r e (250~ and above) to sear the meat, and a sharp

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reduction in t e m p e r a t u r e to finish the cooking. "A Precise Method of Roasting Beef", issued at Illinois in 1907, featured the use of a t h e r m o m e t e r in a beef roast to show when the meat was rare, medium, or well-done, and stated the temperature ranges for the several stages of cooking. For experiments set up to test the merits of one cooking method against another the Illinois station used paired cuts. With such a foundation to build on, it remained for cooperators in the new meat project to work out details of laboratory technique for cooking meat to be tested for palatability. The North Dakota station and the United States Department of Agriculture took the lead in experimenting with various oven t e m p e r a t u r e s and meat t e m p e r a t u r e s on paired rib roasts. In this work other cooperators were the Iowa and the Nebraska stations and the Institute of American Meat Packers. A f t e r preliminary work it was decided t h a t beef ribs would be roasted to the rare stage, 62"C., for judging. In order t h a t the beef might be uniformly rare to provide to several judges comparably cooked slices the oven t e m p e r a t u r e was reduced to 125~ for the finish a f t e r searing at 260 ~ 270~ The principle of searing meat at the s t a r t in a hot oven was accepted without discussion. No seasoning was used on any of the meat to be tested. Standard directions for roasting beef ribs for palatability appeared in the revised project outline of 1927. A supplement issued in 1928 presented directions for roasting loin of pork, baking cured hams and cooking them in water, roasting leg and loin of veal, and leg and shoulder of lamb. Responsibility for developing standard methods of cooking other meats than beef had been apportioned to the several cooperating institutions. The North Dakota station took the lead on veal, Minnesota on fresh pork and bacon, the Institute of American Meat Packers and the Minnesota station on cured ham, and the U. S. Department of Agriculture on lamb. Uniform cooking accomplished by the use of slow oven temperature for the major part of the process was as desirable for these other meats as it was for beef. A meat t h e r m o m e t e r proved to be equally reliable as an indicator of the stage of cooking for beef, veal, pork; and lamb. In working out the technique of cooking veal, pork, and lamb for palatability tests each kind of meat obviously pre-

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sented a problem peculiar to itself. Fresh pork should be cooked thoroughly well done for m a x i m u m palatability and for safety. Those who worked on cured ham suggested t h a t it was best when cooked somewhat less thoroughly then fresh pork. The U. S. Department of Agriculture recommended cooking lamb slightly underdone and cooperators who checked this method indicated their approval. The question of removing the fell from the lamb was raised. When experiments indicated no definite relationship between the fell and the flavor of lamb it was decided not to take it off. All the kinds and cuts of meat studied except veal were best when roasted in the same general way as beef ribs, with the f a t side up on a rack in an uncovered pan. Roasts so placed are self-basting. Veal is too lean to be roasted without some sort of covering, so a lid on the roaster has seemed to furnish the simplest solution.

Methods Extended The subcommittee on methods of cooking presented to the A u g u s t 1931 conference of cooperators a proposed revision of the standard directions which had been issued in 1927 and 1928. A new f e a t u r e is a series of pen-and-ink illustrations which show where to place meat t h e r m o m e t e r s in the different cuts, how to carve these cuts and w h a t muscles to test. These revised directions are to be included in the general revision of the entire project outline, now in progress. Directions for several additional cuts of meat have been added and will appear in the new outline. The Minnesota station has developed a method for the oven cooking of bacon. The U. S. Department of Agriculture presented a method for roasting fresh hams. From the Missouri station came tentative directions for roasting beef chuck and for broiling steaks. Considerable space has been given to the discussion of the development of standard methods for cooking cuts from experimental animals, because of their relation to the general scheme of "Cooperative Meat Investigations." These methods must of necessity be laboratory methods. However, embodying as they do the principles of meat cookery, they can be translated into practical cooking directions for the housewife. In this way "Cooperative Meat Investigations" is contributing to " t h e newer knowledge of meat cookery."

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Thermometer Takes the Guess Out of Cooking Meat In the first place the meat project has popularized the fundamental work done by the Illinois station t h i r t y years ago. Probably the most outstanding single contribution to the newer knowledge of meat cookery is the use of the meat thermometer. Recommended by the Illinois station for testing doneness of meat it has been used in Home Economics classes in many institutions b u t its advantages have not been generally known. Convinced t h a t a t h e r m o m e t e r for meat cooking is j u s t as practical for the housewife as a candy or a deep f a t t h e r m o m e t e r the U. S. Department of Agriculture in 1927 called the attention of leading m a n u f a c t u r e r s to the need for a special short t h e r m o m e t e r of sturdy construction. Accordingly, based on specifications drawn up by the Department in consultation with the United States Bureau of Standards, a special roast meat t h e r m o m e t e r is now manufactured for household use. All the publications on meat cookery t h a t have been issued by the cooperating institutions in the meat project have f e a t u r e d the t h e r m o m e t e r as the best means of telling when a roast is done to the desired turn, no more, no less. More and more the t h e r m o m e t e r is being found to be the only sure guide for the proper cooking of large roasts of beef and pork.

Heat Penetration Varies Next to the t h e r m o m e t e r as a guide, and desirable information in any case, are the figures based on experimental work showing the approximate time per pound required to roast meat when certain oven t e m p e r a t u r e s or other cooking conditions are specified. The number of minutes to the pound obviously depends on the rate of heat penetration. Some interesting points are coming to light about factors that influence the rate of heat penetration, even when the oven t e m p e r a t u r e and the stage of cooking are constant. F o r different cuts of beef, roasted at the Missouri station, the number of minutes per pound varied from 17 to 32 for exceedingly slow cooking to the rare stage. This station states that cuts of beef which do not contain bone are relatively slower to roast then those which do. The U. S. Department of Agriculture has shown that boned and rolled rib roasts require relatively more time

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than standing roasts, confirming earlier work done at the Illinois station. In baking cured hams, whereas a whole ham will cook in 25 to 30 minutes to the pound, a half ham requires 40 to 45 and as high as 55 minutes to the pound. Shape, style of cutting, and composition of roasts are accordingly factors that influence the rate of heat penetration.

Fat Covering Aids Heat Penetration One factor of composition observed to affect the rate of heat penetration of roasts is the thickness of the fat covering on a piece of meat. Data from the Iowa station, Bulletin 272, show a trend towards more rapid heat penetration in large well-finished rib roasted. Highly finished ribs from the carcass contest of the 1930 International Livestock Show roasted by the U. S. Department of Agriculture in December of that year required less than average time for cooking. With lamb it is the same story. In roasting upwards of 2500 legs of lamb with the oven t e m p e r a t u r e and the meat t e m p e r a t u r e constant, the department has observed a range from 24 to 60 minutes per pound. Legs from well-fattened lambs tend to cook more rapidly in relation to their weight than legs from poorly finished lambs. Experiments on pork loin roasts in the Department have indicated that those with heavy f a t covering will cook in fewer minutes to the pound than those with less external fat. In this connection, studies reported by the University of California in 1927 revealed that the rate of heat penetration of roast was increased by external fat, b u t retarded by internal fat. The Illinois station has found t h a t during roasting some of the external fat penetrates into the lean meat and that a good f a t covering is desirable from the standpoint of palatability. Studies on the rate of penetration into p o r k fat, suet, and lean beef are in progress at the Minnesota station. The North Dakota station working on veal, which usually is quite lean, reports that because the rate of heat penetration is very slow when veal is roasted in an open pan it is advisable to use a covered roaster to speed up the cooking. It was observed in the Department that lean muscle of beef round was exceedingly slow to roast in an open pan. Recently, the Dep a r t m e n t has found that ripened lamb cooks more quickly than strictly fresh lamb.

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A special device for hastening the rate of heat penetration into roasts is the metal skewer recommended for beef by the University of California in 1926. By conducting heat into the center of a piece of meat, metal skewers in a roast reduce cooking time and shrinkage. Recently the Minnesota station has confirmed the efficiency of such skewers for meats other than beef. The information gained through cooking thousands of cuts of meat of varying characteristics under the same controlled temperature conditions shows that cooking time per pound is so variable that it is not always a sure guide to successful cooking. The really reliable means of telling how to have meat cooked to the desired stage at the desired time is the roast meat thermometer. By picturing what is happening at the center of a piece of meat in the oven, the t h e r m o m e t e r shows whether the cooking is proceeding rapidly or slowly and consequently whether heat should be decreased or increased in order to have the roast done at the proper time. There is unquestionably much more to be learned about factors t h a t influence the rate of heat penetration in cooking meat. Different fuels and different types of stoves and cooking utensils probably have their specific effects. In this connection, it is encouraging to note the North Dakota station work on the efficiency of certain types of cooking utensils and on fuel consumption in relation to type of oven, method of cooking, and material of which utensils are made. The Missouri station h a s compared gas broilers with electric broilers for steaks. It is to be hoped that there will be more information of this kind to contribute to the newer knowledge of meat cookery. In this day of countless new cooking devices accompanied by extravagant advertising claims, there is a real need for reliable, unbiased information to be made available to the consumer.

Meat May Be Cooked Under Wide Range of Conditions As previously stated, at the time the work on the standard methods was initiated the principle of searing roasts in a hot oven at the beginning of cooking was accepted. There has long been an idea prevalent that only by searing could the juice~ be held in during the cooking process. Several years ago, however, the Missouri station and the Department showed

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t h a t the cooking losses of beef were actually increased by the high temperature used in searing. Recently in the Department this finding has been confirmed for pork loin and leg of lamb. It is entirely possible to roast meat with a constant moderate oven t e m p e r a t u r e and no sem:ing and have it taste and look well. The Missouri station reports good results with the use of constant very slow oven t e m p e r a t u r e not only on tender cuts of beef, but also on some of the less tender cuts, formerly supposed to be satisfactory only when cooked as pot roasts and stews. Apart from the work on searing, experiments on different temperatures for roasting meat have shown t h a t almost any reasonable oven t e m p e r a t u r e can be used. The time required, the shrinkage of the meat, the u n i f o r m i t y of cooking, and the external appearance of the cooked cut will vary according to the oven temperature, but there seems to be no significant modification of the palatability of the meat t h a t can be detected by the measures now employed. So far, roasting has received the g r e a t e s t attention as a cooking method in "Cooperative Meat Investigations." Other methods of cooking meat are under investigation in several s t a t i o n s . The cooking of cured ham in water and under steam pressure has been studied by the Minnesota, Maryland and North Dakota stations and the I n s t i t u t e of American Meat Packers. North Dakota has worked on the braising of veal under controlled temperature conditions, and on the larding of veal and beef. At the Missouri station methods of broiling steaks, both tender and less tender, from beef animals of diff e r e n t classes and grades are being studied. Another promising field which is receiving attention is the selection and cooking of meat for institutional use. In this field the Minnesota and the North Dakota stations and the Institute of American Meat Packers have been conducting investigations.

The Project Offers Wide Opportunity to Home Economists Among recent publications growing out of the national project is a list of definitions of the terms most commonly employed in meat cookery. A great need for such definitions was revealed by a questionnaire sent out by the National Livestock

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and Meat Board several years ago. Accordingly definitions were formulated which it is believed represent the best t h o u g h t of a number of interested persons, directly and indirectly connected with the meat project. In conclusion, we of the home economics field count it a privilege to participate in these studies. Never before have home economics workers had such a wide opportunity to experiment in meat cookery. It has been valuable to observe and cook numbers of cuts from animals of known history. The definitely recorded data from these large numbers of roasts accurately described, cooked according to constant methods and tested for palatability not only have furnished the basic principles for meat cookery, b u t are pointing the way toward studies needed to develop these principles still further. An opportunity exists for careful observations on large numbers of cuts of meat with different characteristics. Their variations in response to the same t r e a t m e n t furnish the basis on which to modify the t r e a t m e n t in such ways as to bring out the best in meat of any particular description. For example, "cooking meat according to the cut" can then be qualified for the degree of fatness, the age, and other inherent characters. With the background of experimental work accumulating, it should some day be possible to say, for instance, j u s t w h a t kind of round steak to broil and what kind of porterhouse not to broil. Sound basic information of this kind is of immediate, popular application. It is of the utmost importance that such i n formation be presented to the teacher, the dietitian and the homemaker in terms of practical, common sense recommendations based on understanding of the problems of every-day life. The presentation of laboratory findings in such t e r m s is not always easy, b u t it does apply the acid test to the value of the contribution. In a project like "Cooperative Meat Investigations" which must by its nature be slow to arrive at some kinds of conclusions, it is well to r e m e m b e r at all times t h a t the goal is the more efficient production of better meat. Cooking has a g r e a t deal to do with the satisfaction with which the meat on the table is received. It is therefore important that home economists not only work on the improvement of meat cooking

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technique i n all its phases, b u t apply the findings in practical terms. The considerable number of publications on meat cookcry already issued by the institutions directly engaged in Cooperative Meat Investigations shows t h a t the home economists are alive to their privileges and responsibilities.

C O O P E R A T I V E MEAT I N V E S T I G A T I O N S D E V E L O P M E N T OF METHODS F O R T H E L A B O R A T O R Y STUDY OF MEAT PAUL E. H O W E

U. S. Department of Agriculture

This assignment was to consider what has been accomplished in the development of adequate methods for the laboratory s t u d y of meat. The President has also suggested that consideration be given to the physical, histological and chemical studies. The physical methods that have commanded the most attention are the tests for tenderness of the raw or cooked meat and the color of the flesh and fat. In the m a t t e r of tenderness there was a certain amount of work done to guide those who were looking for more accurate methods. K. B. Lehman in Germany had developed a mechanical "biter" which was fairly satisfactory but required that the meat be cut across the grain, otherwise the two j a w s would pass between the fibers. At the New Mexico Station some experimental work had been done on a device in which it was hoped to determine the work required to force meat through a hole or holes by means of a plunger. Three institutions, the Bureau of Animal Industry and the Kansas and Illinois Stations, have been particularly interested in developing methods of testing tenderness. The striking fact of most of this work is that a procedure may be fairly satisfactory in measuring some quality in homogeneous material, but that difficulties arise when it is applied to meat. These difficulties are apparently due more to the lack of uniformity of