The process is named after the French microbiologist Louis Pasteur whose research in the 1860s demonstrated that thermal processing would deactivate unwanted microorganisms in wine. By the year 1999, most liquid products were heat treated in a continuous system where heat can be applied using foods that starts with e plate heat exchanger or the direct or indirect use of hot water and steam. Due to the mild heat, there are minor changes to the nutritional quality and sensory characteristics of the treated foods. Louis Pasteur’s pasteurization experiment illustrates the fact that the spoilage of liquid was caused by particles in the air rather than the air itself.

These experiments were important pieces of evidence supporting the idea of the germ theory of disease. The process of heating wine for preservation purposes has been known in China since AD 1117, and was documented in Japan in the diary Tamonin-nikki, written by a series of monks between 1478 and 1618. Much later, in 1768, research performed by Italian priest and scientist Lazzaro Spallanzani proved a product could be made “sterile” after thermal processing. Spallanzani boiled meat broth for one hour, sealed the container immediately after boiling, and noticed that the broth did not spoil and was free from microorganisms. Massy, near Paris, became the first food-bottling factory in the world, preserving a variety of foods in sealed bottles.

Appert’s method was to fill thick, large-mouthed glass bottles with produce of every description, ranging from beef and fowl to eggs, milk and prepared dishes. Appert’s method was so simple and workable that it quickly became widespread. In 1810, British inventor and merchant Peter Durand, also of French origin, patented his own method, but this time in a tin can, so creating the modern-day process of canning foods. A less aggressive method was developed by French chemist Louis Pasteur during an 1864 summer holiday in Arbois. Milk is an excellent medium for microbial growth, and when it is stored at ambient temperature bacteria and other pathogens soon proliferate.