Dhineshkumar.V and Dr.D.Ramasamy
Research Scholar, College of Food and Dairy Technology, TANUVAS, Chennai-52.
Professor and Head, Food Science and Technology, Chennai-52.
Corresponding Author: [email protected]
Bengaluru, March 06, 2016: Enjoyed by more than six billion people worldwide, milk consumption continues to grow apace. As a fresh product from many different animal sources and geographies, milk and milk products require careful handling, processing, and packaging to ensure that they are safe to drink and contaminant-free when they reach consumers.
Milk production is a global enterprise, but a small number of countries/regions dominate the marketplace. The top 10 producers in the 2013 market year and their total milk production in millions of pounds were: European Union–306,659,860; U.S.–201,597,442; India–126,764,500; China–76,058,700; Brazil–71,384,948; Russia–69,224,440; New Zealand–43,382,119; Argentina–26,005,462; Mexico–24,845,842; and Ukraine–24,603,336.
Data collected in 2013 highlights vast differences in production levels per dairy cow among countries. In the U.S., the world’s second largest milk producer, a farmer can expect to achieve 21,865 pounds of milk per animal. That is almost 65 percent more than cows in the European Union (13,303 pounds per cow) and an astonishing 840 percent more than India, the world’s third largest milk producing country at just 2,627 pounds per cow.
The disparity between yields in the U.S. and the rest of the world can be explained by several factors. Dairy farmers in North America prefer the high yielding Holstein cows, which have been bred to maximize milk production. The European Friesian cows favored in Europe and other markets typically have lower yields. Farming methods too have evolved differently in North America, where it is more common for dairy farmers to use milk production hormones; milk cows three times daily, rather than the twice-daily regime popular in other countries, and use total mixed ration feeding systems and large, loose-housing operations.
In the U.S., cows raised in intensive production systems produce most of the milk.Per capita, milk consumption is higher in developed countries: 100 kilograms (kg) per person per year in the U.S. and 70 kg in Europe, compared to less than 40 kg per person in developing countries. Globally, changing consumer habits and population growth have resulted in increasing demand for milk and milk products.
Healthy import and export markets demonstrate the scale of the market and the growing demand for milk and milk products in both developed and developing countries. Rising incomes, population growth, urbanization, and changes in diets are driving the increasing demand for dairy products in developing markets. Global milk production has increased by 50 percent since 1982, from 482 million tons to 754 million tons in 2012. However, the consumption of milk has not risen as fast as that of other livestock products. Meat consumption more than tripled and egg consumption increased 500 percent in the same period.
Nutrient Rich
Milk provides essential nutrients and is an important source of energy, high-quality proteins, and fats. Rich in nutrients, including calcium, magnesium, selenium, riboflavin, vitamin B12, and pantothenic acid, milk is an effective way to add diversity to plant-based diets.
Globally, a wide range of dairy animals produce milk, including traditional herds of dairy cows, but also buffalo, camel, sheep, goats, and yaks as well as horses and donkeys. Each plays an important role in the diets of children and adults and has its own unique composition and balance of nutrients.
The age, breed, farming methods, environment, and season influence the color, flavor, and composition of milk and allow the production of a variety of milk products, including liquid milk, fermented milk, cheese, butter and ghee, condensed milk, evaporated milk, dry milk, or milk powder, cream, whey products, and casein.
Quality Management and Testing
Milk testing and quality control should be carried out at all stages of the food supply chain. Good quality raw milk has to be of normal composition and acidity, free of debris and sediment, free of off-flavors, and free of abnormal colors and odors.
Managing quality through risk analysis, or the identification of potential hazards linked to a product or a process, using Hazard Analysis and Critical Control Points (HACCP) or similar tools, must be applied along the whole supply chain, from the cow to the consumer.
Furthermore, testing to ensure quality can be conducted, including organoleptic characteristics, composition, microbiological contamination, physical and chemical contamination, hygiene, and adulteration.
Contamination
Food businesses need to be aware of the potential sources of milk contamination, as well as their responsibility to identify them and to mitigate risks they pose. From the cow to the consumer, sources for contamination include the following:
• Fecal contamination: soiled animals, particularly the teats, udders, and tails (which are in close proximity to the milking area/equipment);
• Bacterial contamination: poor hygiene and milking practices, including dirty hands and milking equipment, and failure to effectively clean and disinfect teats prior to milking, as well as inadequate cleaning and disinfection of equipment and bulk tanks after milking;
• Abnormal milk: abnormalities including mastitis pathogens, blood, and clots;
• Physical contamination: foreign objects may find their way into milk from milking machinery, bulk tanks, dust, bedding materials, dung, insects, and animal hair; and
• Chemical contamination: mycotoxins from contaminated feed, veterinary product residues, cleaning chemicals, and non-food grade equipment and packaging.
Bacterial Contamination
Despite their natural provenance, milk and milk products, like all foods, are susceptible to foodborne pathogens. Microbiological hazards are a major concern in the dairy sector because milk is an ideal medium for the growth of bacteria and other microbes. These can be introduced into milk from both the environment and the dairy animals themselves.
Numerous surveys have demonstrated that milk has the potential to be a major source of foodborne pathogens that can adversely affect human health. The prevalence of these pathogens is governed by numerous factors, such as farm size, dairy animal headcount, hygiene, and management practices.
The main foodborne pathogens associated with milk-based products include: Salmonella; Shiga toxin-producing Escherichia coli; Listeria monocytogenes; Staphylococcus aureus; Yersinia enterocolitica; Bacillus cereus; and Cronobacter sakazakii (in infant nutrition).
Salmonella species live in the intestinal tract of various animal species, and can be transmitted from dairy animal to raw milk. They cause illnesses such as typhoid fever, paratyphoid fever, and food poisoning.
Escherichia coli is commonly found in the lower intestine of farm animals. Most E. colistrains are harmless, but Shiga toxin-producing serotypes can cause serious food poisoning.
Listeria monocytogenes can cause septicemia and meningitis in humans. It can grow at a wide range of temperatures, including in refrigerated milk-based products. It can also survive minimum pasteurization.
Staphylococcus aureus lives in the bovine mammary gland and can be transferred to milk. It causes a number of diseases in humans and has been identified as the source of food poisoning outbreaks.
Yersinia enterocolitica lives in the intestinal tract of farm animals and causes illnesses with symptoms of fever, abdominal pain, and diarrhea.
Bacillus cereus is a ubiquitous spore forming bacterium. Some strains can produce toxins that can, after ingestion, cause vomiting or diarrhea.
Cronobacter sakazakii has been identified as the source of a very rare form of foodborne illness in premature or otherwise “at-risk” infants, although there is no evidence that it poses any significant risk to general populations.
Infection in humans by the above-mentioned pathogens is often caused by the ingestion of contaminated raw milk, milk that has not been properly pasteurized, and/or the consumption of milk products manufactured from contaminated liquid milk. However, later cross contamination, spore germination, or contamination of ingredients can be another source.
Packaging Protection
Food packaging and food contact materials are also potential sources of chemical food contaminants. Whatever the material, there is potential for the migration of chemicals and other substances from packaging to the product itself, posing a risk to human health.
Migration is of particular relevance for smaller chemical compounds; however it also depends on factors including the physicochemical properties of the migrant, the packaging material, and the food; temperature; storage duration; and packaging size, in proportion to the foodstuff volume.
Therefore, all materials that come into contact with food should be tested to ensure they are safe for use in packaging for the specific food.
Potential for migration varies depending on the packaging material in use. The chemicals that can be transferred are diverse.
Inert materials. These include glass, ceramic and stainless steel. The inert material also provides an effective barrier between the product and its external packaging, such as printer inks and adhesives. Chemicals can only migrate from a container’s inner surface where it is in direct contact with the product.
Non-inert materials. These include paper, cardboard, and plastics, and are much more likely to be a source of chemical migration. Paper and plastic products do not have the same density and small pore size as glass, ceramic, and stainless steel; therefore, it is much easier for contaminants to pass through. For example, printing inks have been shown to migrate through paper and board packaging onto dry foods.
Milk Delivers
By volume, milk is the most consumed dairy product throughout the developing world. In many countries it is very much an essential food as a liquid drink or milk product and as an ingredient in a multitude of other food products. Its composition, and the variations between dairy producing animals, delivers health and nutritional benefits to consumers around the world.
From small-scale farmers in developing markets to commercial dairy farming on a grand scale in the European Union and U.S., responsibility for the safety and quality of milk and milk products lies squarely with the food industry. The nature of dairy herds and milking practices means that there is significant opportunity for milk to harbor a variety of microorganisms and chemical contaminants, with the potential to cause a negative effect on human health. Stakeholders across the food industry must accept these risks and work with third-party laboratories and experts to mitigate and minimize them through risk assessment, improved processing, and product testing.
Allergy or Intolerance
Food allergies affect 220 to 250 million people worldwide, according to the World Allergen Organization. In the U.S., food allergies are responsible for 30,000 anaphylaxis episodes annually, leading to 2,000 hospitalizations and 200 deaths. In Europe, more than 17 million people have a food allergy, and hospital admissions for severe reactions in children have risen seven-fold over the past decade.
Like many other foods, milk can cause an allergic reaction in humans. A milk allergy is a reaction to one or more of the many proteins present in milk. Although milk can be sourced from a variety of animals, as previously mentioned, commercially farmed animals produce antigenically similar milk. As a result, a person with an allergy to cow’s milk will likely also be unable to drink sheep or goat’s milk.
Conclusion
A milk allergy is distinct from lactose intolerance. The former is an immune reaction to food protein, the latter is a non-allergenic food sensitivity related to a person’s inability to produce the enzyme lactase, which is required to digest milk.
In addition, milk and milk products may also become contaminated with other food allergens, such as nuts, shellfish, eggs, fish, milk, peanuts, soy, and wheat through contaminated process lines or through ingredients. However, product testing and implementation of HACCP control plans should reduce these risks.
Corporate Comm India (CCI Newswire)
