Food-Service-Manual-for-Health-Care-Institutions

Food Service Manual for Health Care Institutions
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combination of the two can be used. Dried cheeses also are used to heighten the cheese flavor
in some products.
Milk
Milk, an important component of many prepared foods, requires careful preparation procedures
to prevent curdling and scorching. High temperatures and prolonged cooking coagulate and
toughen milk protein, change milk flavors, and cause caramelization of the lactose in milk. But
the curdling and coagulation of the milk protein can be caused by other factors as well. For example,
table salt and curing salt such as that used in ham and bacon can cause milk to curdle, as can
tannins, found in many vegetables such as potatoes and in chocolate and brown sugar. Strong
food acids can cause almost immediate curdling. Because milk scorches easily, it should be heated
over water or in a steam-jacketed kettle with low steam. Prolonged heating at low temperatures
may darken milk (by caramelization of the lactose) or cause it to lose some of its flavor.
Several techniques can be used in preparing foods that contain milk to decrease the risk of
curdling. For example, the milk can be thickened with flour or cornstarch, as in white sauce
and puddings, to stabilize the milk protein during the cooking process. Salt should not be
added early in the cooking process. Acid ingredients, which should be at the same temperature
as the milk, should be added in small amounts toward the end of the cooking time.
Evaporated milk is whole milk with 50 percent of the water removed. Diluted with an
equal quantity of water, it can be substituted for fresh whole milk in most recipes with good
results because it is more heat stable and resistant to curdling. It produces smooth, even-textured
puddings and white sauces.
For reasons of economy and convenience, nonfat dry milk can be used for many cooking
purposes. Fourteen ounces of nonfat dry milk and 1 gallon of water produce the equivalent of
1 gallon of fresh skim milk. Adding 5 ounces of margarine or other fat to this recipe makes the
equivalent of 1 gallon of fresh, whole milk in fat and calorie content. In many recipes, 1 ⁄2 to
3
⁄4 cup of nonfat dry milk can be added for each cup of liquid to supplement the nutritional
value and protein content of the food.
Dry milk can be combined into food products by several methods. In cakes, cookies, quick
breads, and instant mashed potatoes, milk solids can be added to the other dry ingredients, and
the water needed to reconstitute the dry milk is added with the other liquid ingredients. For
custards, puddings, and similar dishes, dry milk solids should be combined with the sugar. The
water required for reconstitution is added separately. If the milk is to be reconstituted and used
in liquid form, the amount of dry milk specified by the manufacturer’s instructions should be
weighed and the water carefully measured. Once reconstituted, the milk should be refrigerated
immediately and protected from contamination.
Dried cultured buttermilk also is available and convenient to use in many recipes. It is combined
with recipe ingredients in the same manner as nonfat dry milk. Dried cultured buttermilk
should be refrigerated after the container has been opened.
Many desserts use dairy product foams. When air is beaten into cream or evaporated milk,
semistable foam is produced. Cream that contains less than 30 percent milk fat will not whip
without the use of special methods or ingredients. Whipping cream foams to about twice the
original volume and evaporated milk to about three times the original volume. The cream or
milk must be cooler than 40°F (4°C), and bowl and beaters should be thoroughly chilled. One
tablespoon of lemon juice per cup of evaporated milk will help stabilize the foam produced.
The lemon juice should be added after whipping.
If substituting nondairy whipped toppings for whipping cream in recipes, remember that
the nondairy products whip to larger volumes. Therefore, substitutions should be made according
to the quantity of whipped material required by the recipe, rather than by equal volumes
of unwhipped liquid.