A. Class Experiments. Gelatine.
1. Soak a fourth of a teaspoon of gelatine in a tablespoon of cold water for five minutes. Does it dissolve? What has happened? Add two tablespoons of boiling water. Compare the result of putting two tablespoons of boiling water directly on a quarter of a teaspoon of gelatine not been soaked in cold water. Which method will you use in preparing gelatine?
2. Measure the number of tablespoons of gelatine in a box. How much does a tablespoon of gelatine weigh? How much jelly will it make? See directions with the box.
3. Compare the cost, the net weight, and the amount of jelly supposed to be made from packages of at least three different well-known gelatines.
B. Prepare Gelatine Dishes.
Dissolve one tablespoon of gelatine in nine tablespoons of water. Divide into three portions. How much more liquid can you add to each and obtain the proper consistency for jelly?
1. Make the first portion into a plain jelly, using lemon or orange juice for the additional liquid. For the amount of flavoring and sweetening follow the recipes supplied with the box.
2. Make the second portion into a sponge. Follow the recipe for snow pudding.
3. Make the third into a Bavarian cream.
Different flavors may be used, or a single flavor, - as, for example, coffee may be used in all three.
Place each in a wet mold, put in a cool place to harden. If you wish to use them at once, surround the molds with crushed ice and salt.
Gelatine for commerce is made from the skin, ligaments, and bones of animals. It is put on the market in a number of forms. Of these, sheet gelatine is possibly the cheapest, but pulverized gelatine is the most convenient.
As a gelatine jelly usually contains only about two per cent of gelatine, such dishes evidently are not very hearty. For this reason, they make excellent light desserts to use after a substantial meal, or as a hot-weather dish. Since they are also easily digested and absorbed, they are valuable, too, in invalid diets. But, combined with much cream and sugar, a gelatine dish may be made very nutritious.
A word of warning must be given in regard to the use of pineapple and gelatine. This fruit contains a ferment which is capable of liquefying the gelatine, so that if the fruit is used raw, the jelly fails to set. If the pineapple is heated, this ferment is destroyed; so that pineapple jelly may be made with either canned pineapple, or fresh pineapple which has been stewed for a few moments.
In making meat soups, gelatine is formed from the bone and connective tissue which are present in the meat. Since the bones of young animals contain more gelatine-making material than is found in the bones of older animals, while, on the other hand, the meat of older animals has most connective tissue, this explains why veal bones are so often used with beef in soup making. Hutchison quotes experiments which show that the buying of bones to obtain gelatine is much more expensive than adding commercial gelatine to soup, and suggests that the bones themselves should be used only in order to utilize what would otherwise be waste material.
Agar-agar, a Japanese sea-weed, is sometimes used instead of gelatine, especially by vegetarians. It passes through the body without being digested, and so has no food value. It has the advantage of not being so easily liquefied as gelatine and can be made without ice in warm weather. The vegetable gelatines on the market are usually agar-agar preparations.
Irish moss is another seaweed sold in a dried form. It has a peculiar flavor which is greatly relished by some people. Like agar-agar, it is probably not nutritious. When made into a jelly with milk, it may, however, furnish a pleasing variety; and is at least as nourishing as the milk alone.
1. Compare the cost of a plain fruit gelatine with the cost of the same dish made with a "ready-to-mix" preparation.
2. What advantage have the pulverized gelatines over the sheet form?
3. How many classes of gelatine desserts are there? Consult cook books.
4. What relation is there between gelatine and glue?