Experimental cookery

The extent the batter should be mixed depends to a certain degree upon the temperature of the ingredients. If the ingredients are w^arm, the flour proteins absorb more water and at a quicker rate than at low tempera- tures. The sugar dissolves better, and the fat is distributed more readily. Mixing should be shorter w^hen the temperature of the ingredients is high and longer when the temperature is low. But, since the fat creams better at 24° to 28°C., it is preferable to mix the ingredients at these tempera- tures. When the temperature of the ingredients drops to 18° to 19°C. the texture of the cake is not as nice as at 24° or slightly higher, even if creamed thoroughly on a machine. A microscopic study of the distribution of fat in cake batters shows that a very important factor in obtaining velvetiness is the way the fat is dis- tributed throughout the batter. If the fat forms an oil-in-water emulsion the cake is not velvety, for the spheres of fat or oil being surrounded by egg and flour cannot impart the softness called velvetiness to the cake. When the fat is distributed in rather thick layers, the cake is not velvety, for there is not the degree of separation of the other ingredients of the cake by the fat to impart this texture. For a velvety texture in the cake the major portion of the fat in the batter is distributed in very thin films or sheets around the sugar crystals, the air bubbles, and between the other ingredients of the batter. The distribution of the fat in thin films is most readily obtained when the fat is most plastic. Fig. 66 is a photomicrograph of cake batter that shows the butter dis- persed as an oil-in-water emulsion. All the materials were incubated at FAT DISTRIBUTION IN CAKE 493 40°C. and mixed at this temperature. The butter was melted, and during mixing an emulsion was formed. This photomicrograph has a higher mag- nification than the other photomicrographs used in the illustrations, and shows how well the melted fat may be emulsified by mixing. Myers studied the effect of two temperatures of ingredients at the time of combining on the fat distribution in the baked cake. The temperatures used were 25° and 30°C. ; the methods of combining ingredients, the conventional-sponge and conventional; and the fats used, butter and both smooth and grainy lards. The two lards were from the same source. A suf- ficient amount of open-kettle rendered lard for the whole experiment was carefully melted and divided into two portions. One part was allowed to cool slowly in an incubator at 25 °C. with the result that it was granular or grainy with some separated oil. The other portion was cooled within a kettle set in a container into which tap water at 10°-15°C. was running constantly. More than an hour of constant stirring was required before the lard solidified. The product was then set in the constant temperature box at 25 °C. for 12 hours, as suggested by a patent to Procter and Gamble Company. The resulting lard had a very desirable consistency, neither too soft nor too hard and waxy, and was very plastic. The analysis of variance of total scores shows that the variation due to temperature, method of combining, and fat used were all highly significant. A total of 300 cakes was made and the average total scores are given in Table 57. TABLE 57