Dairy Products And Safety
Milk contains nine essential nutrients, making it one of the most nutritious beverages one can enjoy. But from a food safety standpoint, milk poses many challenges. Milk is an excellent growth medium for a variety of both pathogenic and non-pathogenic microorganisms. Its proteins cause it to be listed among the “Big Eight” foods that account for 90% of all food-allergy reactions in the United States. The carbohydrate in milk, lactose, cannot be physically tolerated by millions worldwide.
Pasteurization of Milk
Milk pasteurization is a technology for disinfection and extending the shelf life of milk, which involves heat treatment of the liquid at a certain temperature for a certain time.
Milk became subject to pasteurization as early as the 1890s in the U.S. because bovine tuberculosis and brucellosis were thought to be transmitted to humans through the drinking of raw milk. In 1938, milkborne disease outbreaks constituted 25% of all food- and water-based illness outbreaks. Today, that number is estimated at less than 1%.
So why is pasteurization so important and so effective? Because raw milk can contain any number of dangerous pathogenic organisms, including Bacillus cereus, Campylobacter jejuni, E. coli O157:H7, Listeria monocytogenes and Salmonella.Pasteurization, coupled with a comprehensive food safety program, can greatly reduce or eliminate the possibility of foodborne illness resulting from dairy products,also, pasteurized milk is stored much longer than usual.
When selecting milk at the store, make sure it is properly displayed and pay close attention to the date on the label. All fresh fluid milks should be stored at temperatures below 4 °C and should not be stacked high in the display cases,because upper shelves may be a few degrees warmer than lower ones.
In general, milk should be refrigerated at a temperature of between 0 °C and 4 °C. Keeping milk cold is critical to ensure it stays fresh, lasts longer, and keeps its delicious taste. The key is not to break the "cold chain" between the grocery store and home
Cheese
Although there are many different types of cheeses, some general safety guidelines apply:
1. Refrigerate solid cheese in its original wrap until opened. After opening, rewrap the cheese tightly in moisture proof wrap, such as foil, or place in an airtight container.
2. Buy only pasteurized cheese or hard cheeses.
3. If mold appears, throw away all soft cheeses (with the exception of harmlessly matured cheeses such as blue cheese).
4. Serve cheese at the recommended serving temperature, which varies according to type. Do not leave moist cheese, such as ricotta or mozzarella, out of the refrigerator for longer than 2 hours.
5. Frozen hard cheeses can be used as long as they are properly frozen. Cheeses with a higher water content freeze at a higher temperature than cheeses with a lower water content. Though freezing doesn’t destroy the nutrients in cheese, it affects its texture and quality.
Butter
Storing butter properly, lengthens the shelf life so it can be used over a longer period of time. To prevent a type of spoilage called rancidity, protect butter from heat, light and air by storing it covered in the refrigerator. Rancid butter has an unpleasant taste and smell.
Butter absorbs odors from other foods rapidly. To prevent flavor changes, keep butter wrapped in moisture- and vapor-proof material or in tightly covered containers. For refrigerator storage, leave butter in its original wrapper.
Butter can be stored for up to two weeks at refrigerator temperatures (below 4 °C). Higher temperatures cause off-flavors and unpleasant odors to develop. Butter should not be stored in the butter keeper (set at warmer temperatures) on the refrigerator door longer than two days.
To store butter in the freezer, wrap it in moisture- and vapor-proof freezer packaging material . If properly wrapped and held at -18 °C or lower, butter will keep well in the freezer for six to nine months. Butter should be thawed in the refrigerator or in the microwave, it is not recommended to thaw butter at room temperature.
Yogurt
The natural sugar in milk is converted to lactic acid by means of a bacterial culture producing the creamy, pleasantly tart yogurt. Yogurt is pasteurized to destroy disease-causing microorganisms. Fat and calorie content will differ depending on whether whole, low-fat or fat-free milk is used and whether fruit or sweeteners are added. The label will give the specific information for each yogurt.
Yogurt may be kept well covered in the refrigerator for seven to 10 days at 4°C .Freezing yogurt is not recommended because of the variable results in texture.
Sour cream, Cottage cheese
Sour cream and curd should be stored at 4°C, curd can be stored for 5-7 days after opening, and sour cream for 1-3 weeks.
Sour cream changes during the freezing and thawing process, which means that the fat separates from the liquid part of the cream, this results in a thickened texture that differs from the original texture of sour cream, which is soft and creamy, although for products such as baked goods and soups, you can freeze sour cream for texture and taste without negative impact.
Cottage cheese in its original packaging can be stored in the freezer for up to 3-6 months, however, freezing cottage cheese is generally not recommended, as it may cause a change in taste and texture
