Beyond the Shopping List: The Story of Milk

This longer reference provides the background behind the topic. Read it alongside the recipe collection when you want to connect an ingredient or food idea with a dish to prepare.

In this story

Overview Types of consumption Food product for humans Production worldwide Production yields Price Additives and flavoring

Overview

Milk is usually a white liquid food (but can be shades of yellow, cream, pink, or brown) produced by the mammary glands of lactating mammals. It is the primary source of nutrition for young mammals before they are able to digest solid food. Milk contains many nutrients, including calcium and protein, as well as lactose and saturated fat; the enzyme lactase is needed to break down lactose. Immune factors and immune-modulating components in milk contribute to milk immunity. The first milk, which is called colostrum, contains antibodies and immune-modulating components that strengthen the immune system against many diseases.

As an agricultural product, milk is collected from farm animals, mostly cattle, on a dairy. It is used by humans as a drink and as the base ingredient for dairy products. The US CDC recommends that children over the age of 12 months (the minimum age to stop giving breast milk or formula) should have two servings of milk products a day, and more than six billion people worldwide consume milk and milk products. The ability for adult humans to digest milk relies on lactase persistence, so lactose intolerant individuals have trouble digesting lactose.

In 2011, dairy farms produced around 730 e6tonne of milk from 260 million dairy cows. India is the world's largest producer of milk and the leading exporter of skimmed milk powder. New Zealand, Germany, and the Netherlands are the largest exporters of milk products. Between 750 and 900 million people live in dairy-farming households.

Types of consumption

There are two distinct categories of milk consumption: all infant mammals drink milk directly from their mothers' bodies, and it is their primary source of nutrition; and humans obtain milk from other mammals for consumption by humans of all ages, as one component of a varied diet.

Food product for humans

In many cultures, especially in the West, humans continue to consume milk beyond infancy, using the milk of other mammals (especially cattle, goats and sheep) as a food product. Initially, the ability to digest milk was limited to children as adults did not produce lactase, an enzyme necessary for digesting the lactose in milk. People therefore converted milk to curd, cheese, and other products to reduce the levels of lactose. Thousands of years ago, a chance mutation spread in human populations in northwestern Europe that enabled the production of lactase in adulthood. This mutation allowed milk to be used as a new source of nutrition which could sustain populations when other food sources failed. Milk is processed into a variety of products such as cream, butter, yogurt, kefir, ice cream and cheese.

Modern industrial processes use milk to produce casein, whey protein, lactose, condensed milk, powdered milk, and many other food-additives and industrial products.

Production worldwide

In 2012, the largest producer of milk and milk products was India, followed by the United States of America, China, Pakistan and Brazil. All 28 European Union members together produced 153.8 e6tonne of milk in 2013, the largest by any politico-economic union.

Increasing affluence in developing countries, as well as increased promotion of milk and milk products, has led to a rise in milk consumption in developing countries in recent years. In turn, the opportunities presented by these growing markets have attracted investments by multinational dairy firms. Nevertheless, in many countries production remains on a small scale and presents significant opportunities for diversification of income sources by small farms. Local milk collection centers, where milk is collected and chilled prior to being transferred to urban dairies, are a good example of where farmers have been able to work on a cooperative basis, particularly in countries such as India.

Production yields

FAO reports Israel dairy farms are the most productive in the world, with a yield of 12,546 kg milk per cow per year. This survey over 2001 and 2007 was conducted by ICAR (International Committee for Animal Recording) across 17 developed countries. The survey found that the average herd size in these developed countries increased from 74 to 99 cows per herd between 2001 and 2007. A dairy farm had an average of 19 cows per herd in Norway, and 337 in New Zealand. Annual milk production in the same period increased from 7,726 to 8,550 kg per cow in these developed countries. The lowest average production was in New Zealand at 3,974 kg per cow. The milk yield per cow depended on production systems, nutrition of the cows, and only to a minor extent different genetic potential of the animals.

What the cow ate made the most impact on the production obtained. New Zealand cows with the lowest yield per year grazed all year, in contrast to Israel with the highest yield where the cows ate in barns with an energy-rich mixed diet.

The milk yield per cow in the United States was 9,954 kg per year in 2010. In contrast, the milk yields per cow in India and China– the second and third largest producers– were respectively 1,154 kg and 2,282 kg per year.

Price

It was reported in 2007 that with increased worldwide prosperity and the competition of bio-fuel production for feed stocks, both the demand for and the price of milk had substantially increased worldwide. Particularly notable was the rapid increase of consumption of milk in China and the rise of the price of milk in the United States above the government subsidized price. In 2010 the Department of Agriculture predicted farmers would receive an average of 1.35 $/USgal of cow's milk, which is down 30 ¢/USgal from 2007 and below the break-even point for many cattle farmers.

Additives and flavoring

Commercially sold milk commonly has vitamin D added to it to make up for lack of exposure to UVB radiation; in 1938, Consumer Reports noted that vitamin D supplementation in milk could protect against rickets. Reduced-fat milks often have added vitamin A palmitate to compensate for the loss of the vitamin during fat removal; in the United States this results in reduced fat milks having a higher vitamin A content than whole milk. Milk often has flavoring added to it for better taste or as a means of improving sales. Chocolate milk has been sold for many years and has been followed more recently by strawberry milk and others.

Some nutritionists have criticized flavored milk for adding sugar, usually in the form of high-fructose corn syrup, to the diets of children who are already commonly obese in the US.