MILK AND MILK PRODUCTS

Milk- is the lacteal secretion of mammary glands intended for the nourishment of young mammals. Milk is the only food for which there seems to be adequate substitute. It constitutes about the entire diet for the young of all mammals.

MILK PROCESSING

Pasteurization- The process of heating milk to a temperature of at least 63°C or 145°F and holding it at that temperature for 30 minutes. It destroys all pathogenic microorganisms and most of the nonpathogenic bacteria as well. Another process is the use of ultrahigh-temperature, milk may be heated to a temperature of 89 to 90°C of 192 to 194°F or above for 1 second or less.

Homogenization- Consist of forcing milk or cream under pressure through a small aperture in a machine called a homogenizer in order to break up the fat into much smaller globules, which will remain dispersed. Pasteurization after homogenization retards the development of rancidity because it destroys the enzymes that could otherwise attack the more highly dispersed fat.

Fortification- Consist of the addition of certain nutrients to milk as a means of improving the nutritional inadequacies of milk or as a means of exploiting popular interest in nutrition.

MARKET FORMS OF MILK

WHOLE MILK-from the time it was collected from the animal milk. It may be raw, Whole milk is milk whose composition has not been altered pasteurized or sterilized.

RAW MILK- is fresh whole milk that has not undergone any heat. treatment. Availability of this milk form is generally limited to families who own milking animals such as carabao, goat or dairy cattle.

At present, raw milk is sold in recycled bottles in all sizes and shapes. This is the form that may be easily the adulterated and the consumer should beware of this. Adulterated milk is difficult to differentiate from whole milk by appearance alone

Possible adulterants and the ways of detecting them in milk are as

follows:

Water- Adulteration with water may be detected by freezing point determination. The average freezing point of whole cow's milk is -0.50°C with a possible range of -0.525 to 0-C.

Rice Washing- This may be detected by reaction of iodine with rice starch. If milk gives a blue color with iodine, then it is likely adulterated with rice washing or other starches.

Coconut Milk -This may be detected by resorcinol test which gives a violet color of the milk is adulterated with gata.

PASTEURIZED MILK

-is fresh whole milk, which has been heated to temperature high enough to kill pathogenic microorganisms and to prolong its storage life but not high enough to alter the organoleptic qualities of the milk.

STERILIZED WHOLE MILK

Sterilized whole milk is canned whole milk that has undergone heating at temperatures much higher than 100°C (212°F) for a few seconds.

SKIM MILK

In skim milk most of the fat is removed thus reducing the fat content to about one percent of the whole milk. It is often fortified with Vitamins A and D.

LOW FAT MILK

 usually has between 0.5 to 2.0% milk fat. depending on the regulation. Low fat milk maybe labeled 2% on 2 to 10 milk. These milk may have extra nonfat milk solid added, making the protein and carbohydrate content slightly higher than in skim milk.

 CONCENTRATED MILK

- may be fresh, frozen, evaporated or dried. Milk is concentrated by the removal of water in varying amounts. The milk may be reconstituted to its original form by adding water. Concentrated fresh milk is first pasteurized and homogenized and then has 2/3 of the water removed at low temperatures under vacuum.

Evaporated Milk- Whole milk has slightly more than half its water evaporated in vacuum.

Sweetened Condensed Milk- Has about 15% sugar added to the milk, after which the product is concentrated to about 1/3 its former volume. Because of the 42% sucrose content of the finished product it acts as a preservative, the milk is not sterilized after canning.

Nonfat Dry Milk- Made from fresh pasteurized skim milk by removing about 2/3 of water under vacuum and then spraying this concentrated milk into a chamber of hot filtered air. This process produces fine powder of very low moisture content, about 3%

.

Dried Whole Milk- Made from fresh whole milk with water removed by the same procedure as is used for nonfat dry milk. Dried whole milk contains not less than 26% milk fat and not more than 5% moisture. Because of the fat content, it has a poorer keeping quality than dried skim milk.

Cans of evaporated and condensed milk should be turned every few weeks because of the solids tend to settle. The browning of evaporated milk and condensed milk are probably of the Millard reaction type (sugar-protein interaction) and occurs during both sterilization and storage. The rate of browning is greater at room temperature and with longer time of storage. If browning occurs, there will be some decrease in the quality of protein in the milk The best storage for evaporated milk is bout 4°C or 40 F

TONED MILK

Toning is a process of altering the composition of natural milk to a standard composition of 3% fat and 9% non-fat solids or other standard proportion preferred.

INFANT FEED FORMULAS

Infant feed formulas are usually powdered products containing milk components and other substances to make a product, which is a good substitute for human milk. They are not classified as milk because they have been considerably altered in composition. They are usually the only source of nourishment of infants who cannot be breast-fed.

CANNED AND FROZEN WHOLE MILKS

Fresh whole milk that is homogenized may be sterilized at a temperature of 132 to 138 C or 270 to 280°F for 8 to 10 seconds, after which it is canned aseptically. It may be stored at room temperature until opened, after which it must be refrigerated. Canned whole milk is available chiefly for use on ships or for export for other countries, where milk is less plentiful. Pasteurized, homogenized, whole milk can be quick-frozen but keeps best if it is held at a temperature below -23 C or -10 F until it is used. Quick-frozen milk should be used soon after defrosting.

 

SOFT-CURD MILK

Natural milk for some cows forms a softer curd during digestion than that from other animals. Natural soft-curd milk has a lower percentage of casein, calcium and phosphorous than does average milk. It is accomplished by the removal of about 20% of the original calcium and phosphorous and by a brief digestion with pancreatic enzymes.

 LOW-SODIUM MILK

Fresh whole milk may be passed through an ion exchange resin to replace 90% or more of its sodium with potassium. The low-sodium milk produced is pasteurized and homogenized and may be canned or dried. Some B vitamins and calcium are lost in processing but this milk has special uses in sodium-restricted diets.

MALTED MILK

Malted milk is a dry mixture of whole milk and other liquid obtained by cooking barley malt and wheat in water. Some malted milk used for beverages are flavored with chocolate.

CULTURED MILK

- are made from pasteurized milk by adding certain desirable bacterial cultures and controlling their growth. Yogurt is usually cultured from partially skimmed milk with the addition of a mixed culture of one or more strains of microorganisms, such a Streptococcus thermophilus, Bacterium bulgaricus and Plocamo bacterium yoghurted.

FLAVORED MILK AND MILK DRINKS

- is whole milk with a flavored syrup or powder sugar added. A flavored milk drink is skim or partially skimmed milk similarly flavored and sweetened, Chocolate milk usually contains 1% cocoa with 5% sugar and less than 1% stabilizers.

FILLED AND IMITATION MILKS

Filled milk is made by combining fats or oils other than milk fat with milk solids. The resulting product appears very much like milk

 STORAGE OF MILK

The various forms of canned evaporated milk should be stored in a cool dry place.

Sweetened condensed milk in opened can keep longer than evaporated milk without refrigeration because its sugar content serves as preservative.

Whole milk, whether raw, pasteurized or in opened can should be refrigerated whenever not in use.

CHEESE

 This is a solid milk or dairy product made mainly of casein upon its coagulation from milk by acid of the enzyme rennin. It is a product made from curd obtained from the whole, partly skimmed, or skimmed milk of cows, or from milk of other animals, with or without added cream, by coagulating with rennet, lactic acid or other suitable enzyme or acid, with or without further treatment of the separated curd by heat or pressure, or by means of ripening ferments, special molds, or seasoning.

CLASSIFICATION OF CHEESE

According to Moisture Content

Soft cheeses have a very high moisture content ranging from 55 to 80 percent, e.g., cream cheese. Semi-soft cheeses cheddar

cheese, mozzarella

have 34 to 55 percent moisture. e.g. Hard cheeses have 13 to 34 percent moisture. e.g., parmesan cheese

According to the Ripening Treatment

Ripening may be defined as the change in physical and chemical properties, such as aroma, flavor, textures and composition, that takes place between the time of precipitation of the curd and the time when the cheese develops the desired characteristics for its type.

Unripened, e.g., kesong puti, cream cheese, mozzarella.

Ripened, e.g., cheddar cheese, edam cheese (keso de bola)

PREPARATION OF CHEESE

Cold-Pack Cheese- Requires grinding and mixing together one or more varieties of cheese without the aid of heat make cold pack or club cheese. Acid, water, salt, coloring, and spices may be added, but the final moisture content must not exceed that permitted fort the variety of natural cheese from which it was prepared. The cheese is packaged in jars or in moisture-proof packages in retail-size units.

Process Cheese- Process cheese is made by grinding and mixing together different samples of natural cheese with the aid of heat and an emulsifying agent. A selected blend of cheese is used, or a portion of the same variety selected at different stages of ripeness, and the product is pasteurized before packaging. The cheese is ground and heated with sufficient water added to replace that lost by evaporation.

Process Cheese Foods- Variations of process cheese are produced that, although similar to process cheese, contain more moisture and less fat. Cheese food is milder in flavor and has a softer texture than process cheese because of its higher moisture content.

DIFFERENT KINDS OF CHEESE

NATIVE CHEESE OR KESONG PUTI- The native cheese is actually a semi-soft cheese with water content of about 52 percent. It is made from carabao milk. Native cheese making in the Philippines is an old cottage industry in the provinces of Laguna Bulacan and Cebu.

 CHEDDAR CHEESE

This is the processed cheese widely available in supermarkets and grocery stores in the Philippines. It is usually packaged in carbon boxes with aluminum foil enclosing it and does not need refrigeration until opened. They are conveniently used in macaroni and spaghetti dishes, in cheese pimiento canapés or in simple cheese sandwiches Cheese is a common food item to stock as it serves as a very convenient food to serve for unexpected guest.

Cheddar cheese is ripened cheese by lactic acid bacteria with medium water content of 34 to 45%. Its manufacture is not generally done in this country hence the reader is referred to Potter for the details of its manufacture. It is called Cheddar because it is the leading cheese style manufactured in the United States. It is also the most popular cheese in Canada and England. However, in these counties the cheese is usually not processed, but is eaten as natural cheese after ripening somewhat.

CREAM CHEESE

This is a soft, unripened cheese. It is spreadable. It has a creamy white smooth appearance prepared by coagulating case in with rennet after the milk has slightly soured. It needs to be refrigerated. It makes a delicious sandwich and cracker spread as well as dressing for fruit salads. It is also one of the most expensive.

MOZARELLA

This is semi-soft cheese with 45 to 55 percent water and is used for some pizza pies and lasagna. It is mild, delicate unripened cheese that originated from Italy.

EDAM CHEESE

Like cheddar cheese, this is a semi-soft cheese with 34 to 45 percent water. It is ripened cheese but with no gas holes. This is the well-known keso de bola available at Christmas time. It is ball-shaped with bright red paraffin coating. It has smooth solid texture and mild-nut flavor and is saltier than cheddar cheese. It originated from Holland. It blends well to grating for such dishes as baked macaroni.

PARMESSAN CHEESE

This is a hard cheese with 13 to 34 percent water. This is usually available in the grated form. It has a salty and smokey flavor and a yellow-white color. It originated from Italy.

BLUE CHEESE

Used in salad dressings, blue or bleu cheese is a semi-soft cheese with blue mold growing throughout the curd. It is mold-ripened which has a sharp salty tangy flavor. It is white but with blue veins, hence the name. The blue color vein is produced during the ripening period by the blue-green mold Penicillin Roqueforti. The blue color is actually from the spore of the mold.

SWISS CHEESE

This is a hard cheese that is well ripened. The bacterial ripening process gives it large shiny holes, which distinguishes it from other cheese. It has a pale creamy color and can impress one as having a somewhat soapy taste.

LIMBURGER

A bacteria ripened soft cheese. It is semi-soft, smooth and creamy yellow. It is known for its offensive odor possibly due to protect breakdown during ripening which is obvious to those who have not developed a taste for it. It originated from Belgium

GOUDA

This is a firm cheese that is pale yellow which is a mild nut-like flavor. It originated from Holland. Like Edam cheese it has a red wax coating and has the shape of a ball, it is smaller.

PROVOLONE

It has a smooth firm texture. Sometimes pieces of salami are incorporated in the cheese. This type originated from Italy.

GORGONZOLA

This is an off-white, crumbly and pungent semi-hard cheese that is mold ripened. Like blue cheese. It also has blue veins produced by Penicillium roqueforti. It has a spicy, tangy and peppery flavor. It originated from Italy.

 ROQUEFORT

This is another blue-veined cheese like Gorgonzola and blue cheese and is made of sheep's milk. It is a product of France. Penicillium Roqueforti also produces the blue color. It is the most famous of all blue veined cheese.

ICE CREAM

Ice creams are milk products and frozen desserts that are quite popular in the Philippines especially in hot summer days. They are frozen mixtures of cream and milk, sugar, flavoring and stabilizers Flavorings are usually tropical seasonal fruits and nuts of which the Philipines is well-known, example are mango, atis, avocado, macapurt kasey nut and langka. Stabilizers may be agar or gelatin.

 

Cream

is the fat of milk, which separates by gravity or by the use of separator from other constituents of milk

CLASSIFICATION OF CREAM

Whipping Cream- Contains not less than 30% fat. Heavy whipping cream contains not less than 36% fat.

Light or Coffee Cream- Contains 18% fat; thinner than whipping cream.

Half-and-Half- Mixture of milk and light cream and contains not less than 10.5% fat.