Experimental cookery

at which egg coagulates is one explanation. The proportion of sugar in butterscotch fillings in different recipes varies from about 15 to 25 per cent, or 15 to 25 grams per 100 grams of filling. A usual procedure is to cook the sugar, cornstarch or flour, and scalded milk until thick. This mixture is often added to the beaten yolks by stirring the hot mixture into the yolks. Sometimes it is considered that the hot milk mixture will coagulate or cook the egg yolk sufficiently. However, if the temperature drops below 80°C. during this procedure and the mixture is not reheated the egg yolks will not be cooked sufficiently. The filling appears thick at the time, but on standing it becomes runny. If sugar is added to uncooked egg yolks, mixed, and left to stand for a few minutes the mixture appears thinner and more runny. If the yolks are not cooked sufficiently they act in much the same way, the sugar dissolving in the uncooked yolk and the filling becoming runny. This has never been observed by the author if the mixture is heated to a sufficiently high temperature after the egg yolks are added. The same thing may occur in chocolate and lemon pie fillings, although this in some instances is due to not using enough starch, the action of the acid on the smaller amount of starch lessening the stiffness of the filling. Another possible cause is the tannin of the brow^n sugar, because the tannin has a dehydrating effect on many sols. But to date it has not been possible to obtain thinning in the butterscotch filling by adding slightly more tannin than might be found in the sugar. Baked products. The addition of sugar to egg in baked products also tends to delay coagulation or peptize the egg proteins and will be discussed further under angel cake and cakes containing fats. Cooked Salad Dressings Vinegar, lemon juice, or a mixture of the two, is used in cooked salad dressings. The two acids do not behave alike, particularly in regard to curdling. The lemon juice contains citric acid and salts. Vinegar contains acetic acid, and cider vinegar contains salts. If mustard, sugar, and salt are kept constant in the recipe given in Experiment 65 with 72 grams of egg yolk and a total of a cup of liquid, results similar to the following may be obtained, provided the rate of heating is the same in each case. The mixture is cooked in the upper part of a double boiler, 12 to 15 minutes being required for the cooking process. pW Coats spoon Water about °c. 'inegar Vs cup VS cup 4.2 82 to 85 'inegar X cup K cup 3.9 78 to 80 'inegar K cup }4 cup 3.6 76 to 78 emon juice yi cup % cup 3.6 82 to 85 emon juice % cup % cup ?>.?> 78 to 80 emon juice H cup Vi cup 2.8 76 to 78 COOKED SALAD DRESSINGS 339