Milk heat treatment – pasteurization in history

Pasteurization, the name is derived from that of Louis Pasteur, whose discoveries in the 1860s and 1870s demonstrated that heating liquids, especially wines, to fairly low temperatures, such as 60°C, improved the keeping quality during storage.

In the middle of nineteenth century, commercial winemaker approached Louis Pasteur to seek a solution of abnormal fermentation and subsequent spoilage of wines and beers. Pasteur studied the problem during 1864–65 and found that some microorganisms are the root cause of abnormal fermentation leading to early spoilage of wines and it can be prevented by heating the wine around 60°C, which kills these microorganisms.

William Dewes recommended heating milk in the home before feeding to infants some 40 years before Pasteur conducted his experiments. Dewes observed that if the milk was heated to boiling point and cooled quickly, the tendency to spoil was reduced. This method was successful in reducing infant morbidity and mortality rates.

Also preceding Pasteur was the contribution of Gail Borden who, in 1853, patented a process for heating and condensing milk under vacuum followed by addition of sugar for preservation.

In 1867 Pasteur applies heat to milk and reports the process postponed milk souring.

The first application of pasteurizing heat treatments to milk may have been performed by Franz von Soxhlet in 1886, who pasteurized bottled milk fed to infants.

The first commercial pasteurizer was introduced in Germany in 1882, but it was not until 1893 that a commercial unit was established in the U.S. for pasteurization of raw milk.

Gerber and Wieske pasteurized milk in bottles at 65°C for 1 h as early as 1888. The first commercial pasteurizer was made in Germany in 1882; pasteurization on a commercial scale quickly became common practice in Denmark and Sweden in the mid-1880s.

In Denmark and Sweden, commercial pasteurization of milk was common as early as the mid-1880s, due in part to the early recognition by Danish butter makers of its merits. However, cities in the United States were much slower to openly embrace pasteurization techniques.

In the early 1900s, in Arizona, Jane H. Rider "publicized the link between infant mortality and contaminated milk, and finally convinced the dairy industry to pasteurize milk."

The first pasteurized milk ordinance was published in 1924 in the November issue of Public Health Reports; pasteurization was defined as a heating process of not less than 142°F (61.1°C) for 30 min in approved equipment.

In 1956 minimum temperature for vat pasteurization was raised from 142°F of to 145°F of based on heat resistance of Coxiella burnetii. Based on University of California Davis studies in late 1940's 1966 FDA memorandum accepts dual stem (CIP) flow diversion device to be used in HTST systems.

Today, pasteurization is used widely in the dairy industry and other food processing industries to achieve food preservation and food safety.

Milk heat treatment – pasteurization in history 

Historical Development of UHT Milk

The birth of high heat treatment and canning as a means of preserving food began in France in the early 1800s. By 1839, tin-coated steel containers were widely in use.

UHT processing was developed as early as 1938, aseptic processing, which enabled the distribution of milk without refrigeration, commenced only in 1961.

The various types of heating systems such as steam injection and infusion, were developed for UHT heating to achieve a better sterile product, however, the difficulty of packaging the sterile milk without recontamination into suitable containers for transport hindered the commercialization of UHT products until 1953.

The first system consisting of indirect heating which milk was indirectly heated at 125ºC with a holding time of 6 minutes was manufactured in 1893, only 11 years after the first commercial pasteurizer was used.

Patented in 1912, the continuous flow direct heating method mixed steam with milk to achieve temperatures of 130 to 140ºC. Development was hindered due to contamination potential without commercial aseptic systems. This process avoided the burn on encountered in the indirect heating.

The development of aseptic processing in the United States started through the efforts of C. Olin Ball, and hot-cool-fill process was commercialized in 1938 for a chocolate milk beverage.

UHT processed milk produced in an innovative heater known as Uperiser, and aseptically packed in cans, was first developed in Switzerland in 1953, through the collaborative efforts of a dairy company and a machinery manufacturing firm.

A similar heating technique has employed for long-shelf-life milk but this has aseptically packaged into a tetrahedral paperboard carton for sale in Switzerland in 1961. Tetra Pak pioneered its own continuous UHT process and aseptic packaging systems, and so kick started the growth of the UHT milk segment.

In 1964, ice cream mix and concentrated milk formulations UHT heat treated with direct heat and packaged in four-liter cans. This represented the first commercial aseptic production in Australia.
Historical Development of UHT Milk

History of evaporated milk

Evaporated milk is the commercial name for sterilized unsweetened condensed milk, that is, fresh cow's milk from which a considerable portion of the water has been removed.

By the end of the American Civil War, sweetened condensed milk had grown in popularity, and its success encouraged the development of evaporated milk.

The basic process for preservation of unsweetened condensed milk by heat sterilization was conceived by John B. Meyenberg in 1882, a Swiss citizen, and an employee of the Anglo Swiss Condensed Milk Company. Basic principle of the process was the preservation of unsweetened condensed milk by heat sterilization, by steaming under pressure.

He suggested the idea to the company but was rejected. Meyenberg’s process removed about 60 percent of the water in milk. The remainder was homogenized, canned, and sterilized. The evaporated milk, which occupied far less space than fresh milk, could remain in cans for over a year.

Meyenberg obtained the two United States patents for his process and sterilization apparatus, published on November 25, 1884.

He formed Helvetia Milk Condensing Company, the first unsweetened evaporated milk plant on February 14, 1885, with a number of farmers, and businessmen from Mountain, Illinois, as shareholders. By June 14, 1885, “First Canned Mountain Evaporated Cream” was ready to be put on. The first product was called Highland Evaporated Cream.
History of evaporated milk

Pasteurization of milk in bottles

The custom of preserving milk by heat may be 'as old as the cow and the use of fire'. Pasteurization, named after French scientist Louis Pasteur, was introduced in milk in the late 1800s. The first application of pasteurizing heat treatments to milk may have been performed by Soxhlet, who pasteurized bottled milk fed to infants.

In 1880, British milk bottles were first produced by the Express Dairy Company. Gerber and Wieske pasteurized milk in bottles at 65°C for 1 h as early as 1888. Pasteurization in bottles has been practiced in certain localities for a considerable period of time. Pasteurization in bottles by the process of Gerber, which consists of heating milk in bottles for one hour at 65° C. (149° F.) during which they are agitated, had been practiced in their dairies for 15 years previous to 1903.

By 1898, pasteurization of all bottled milk was made compulsory in Denmark. The process of pasteurizing in bottles consists in bottling the milk in specialty constructed bottles of sufficient size to allow a space in the top of the bottle to take care of the expansion of the milk during heating.

After the milk in the bottles has reached the pasteurizing temperatures, the temperature is maintained for 30 minutes; the hot water is then replaced by cold and the milk cooled.

The first commercial pasteurizer was made in Germany in 1882, using a high-temperature, short-time (HTST) process; pasteurization on a commercial scale quickly became common practice in Denmark and Sweden in the mid-1880s. In 1894 – Anthony Hailwood from England developed the milk pasteurization process to create sterilized milk, and became the first person to sell sterilized milk in the United Kingdom.

What is believed to be the first commercially-operated milk pasteurizer in the United States of America (USA) was installed in Bloomville, New York in 1893.
Pasteurization of milk in bottles