FOODS NUTRITION. 491 



Experimental researches on heredity in silkworms, (t. Coutaone {Bui. Sci. 

 F)-ance et Belg., 37 (190,1), pp. 1-194, pfs. 9, figs. 7). — An extended study was made 

 of the influence of various conditions upon the various races of silkworms with 

 special reference to the transmission of these characters in hybrids or pure-bred 

 descendants of the iniiivichial silkworms upon which experiments were made. 

 These experiments were undertaken chiefly from a biological standpoint, and thus 

 far have not led to definite results which can be utilized in practical sericulture. 



It was found that the quality and quantity of the silk could be considerably influ- 

 enced by temperature, moisture, and other conditions under which the silkworms 

 were maintained. In a certain percentage of cases success was had in securing the 

 transmission of especially desirable characters from parents to offspring. It was 

 found that the probability of the transmission of acquired characters to offspring 

 could be stated with some degree of accuracy according to mathematical formulas. 



FOODS NUTRITION. 



Roasting- of beef, Isabel Bevier and Elizabeth C. Sprague {Illinois Sta. Circ. 

 71, pi>. 30). — The influence of different shapes and sizes of pans, time of cooking, 

 heat of the oven, and other factors upon the character of roasted meat (beef) was 

 studied with the special i)urpose of securing data on the effects of cooking. 



In a comparison of an oval concave pan with oj)en and closed rectangular pans 

 with flat bottoms, it was found that so far as total losses in weight were concerned, 

 the shape and size of the pan did not seem to be of great importance. So far as 

 color and consequently the flavor of the drippings were concerned, the area of the 

 pan and its shape were important, the pan with the smaller area giving the lighter 

 colored drippings in the experiments reported. 



"If the whole amount of drippings was used for gravy, the darkening if not exces- 

 sive might not be undesirable, but because of the number of uses for the excessive 

 fat in drippings, it is desirable to avoid the darkening of them. Moreover, authority 

 can be found for the idea that this darkening means that the fat was heated to such 

 a temperature as to render it less digestible. ' ' 



The results obtained with different sized pans were not definite as regards the 

 losses in weight in cooking. In comparing open and closed pans it was found that 

 the total losses in weight in roasting were greater in the open pan. However, when 

 cooked in a closed pan the meat was inferior in flavor, and was not as attractive in 

 appearance, since it did not brown well, nor was the color satisfactory if browned 

 outside the pan and subsequently cooked. The meat cooked to a greater degree in 

 the closed pan in 15 minutes than in the open pan. When cooked in a closed pan 

 a larger percentage of the material lost was recovered in the drippings, owing to the 

 fact that in the open pan the drippings are almost water free, while in the closed 

 pa.n considerable water is retained. 



As regards the effect of temperature, in the 14 experiments in which this factor 

 was considered the heat of the oven ranged from 83 to 260° C, and the total loss in 

 weight from 5.9 per cent to 20.6 per cent, which was less than one-sixteenth of the 

 total weight of the beef roast used. In general, the higher the temperature the 

 greater the loss in roasting. A temperature of not less than 249° C. was required for 

 the development of the so-called osmazome and the flavors in the meat. When meat 

 is baked for a short time at a very high temperature, 260° C, the outside layer is apt 

 to be overdone and the center too rare for use. When baked very slowly in a special 

 oven at a comparatively low temperature it was very evenly cooked throughout and 

 the juices were well retained, but the savoriness and flavor produced by higher tem- 

 peratures were lacking. Even if the meat was seared before cooking in this oven it 

 did not retain this appearance, but came from the oven gray and miattractive. "If 



