Experimental cookery

may not coagulate in the presence of starch, hence not thicken the salad dressing. Bancroft and Rutzler, quoting Berlinsson, state that "albumin is prevented from coagulating even in boiling water by the presence of starch." However, this appears contrary to observed results in food prepara- tion. Possibly there needs to be a certain concentration of starch before coagulation is prevented or peptization of the egg protein may occur when heated above the temperature for coagulation of the egg protein. It will, at least, be an interesting point to investigate. Eggs Cooked in the Shell Effect of coagulation at low and high temperatures. Eggs cooked in water held at 70 °C. are not firm like those that are cooked in boiling water. The white cooked at 70°C. is very soft and jelly-like in consist- ency. The yolk held at this temperature for an hour or longer has the appearance of an uncooked yolk, but is more viscous, more waxy, thicker, and does not flow like the uncooked yolk. The color also remains more like that of the uncooked yolk, a deeper orange, instead of the yellow which is developed in eggs cooked at higher temperatures. The white of an egg cooked at least 12 minutes in boiling water is rather firm and may be tough. Eggs cooked at temperatures between 70° and 100°C. have tex- tures intermediate between the ones described above, i.e., they are firmer than the former and usually more tender than the latter. By cooking for a short time at a higher temperature the outer edge of the white may be firm to a depth depending on time of cooking, a portion near the yolk may be unchanged, and the yolk may be unchanged or the outer portion may be slightly cooked. The softer coagulum at the lower cooking temperature has been ex- plained as due to the effect of low temperature. Robertson suggests that it may be due to only partial coagulation of the protein at the low tem- perature. The white of some eggs is often more tender than that of other eggs cooked in the same lot. Perhaps this may be explained by the reaction, those which are more alkaline coagulating less readily. There is also the possibil- ity that the white of eggs cooked an extremely long time may become more tender. Barmore mixed egg white thoroughly and placed it in a cement briquette mold. The mold was immersed in water of the desired temperature and left 40 minutes. The tensile strength and the depth a steel ball and rod would penetrate were determined. Below 77.5°C. the samples were too tender to handle. The three tests all indicated a decided increase in tenderness as the temperature of coagulation was reduced with the exception of the steel ball at 93° and 101 °C. Here the data indicated that the change may have decreased instead of increasing the toughness. The other tests gave opposite results at these temperatures. POACHED EGGS 341 Rate o£ heat penetration. The higher the temperature of the cooking water, the more rapid is the rate of heat penetration. As the temperature of the egg and water become more nearly equal the rate of heat trans- ference is very much slower, but the temperature at the center of the yolk even after cooking in boiling water for 4 hours or longer is never quite as high as that of the water, but is a fraction of a degree lower.