Pasteurizer (machine)

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A pasteurizer or pasteurizer , also obsolete pasteutizing apparatus , is a device that makes use of the effect of preserving drinks or food, discovered by Louis Pasteur and named after him . They are also known as warmers , because they warm up the goods to be pasteurized for a short time. There are different classifications of past taxes.

History

Soon after their invention, pastutization devices were used to kill tuberculosis bacteria and other germs that had been transferred to raw milk by infected cows , in order to prevent infants or schoolchildren in particular from becoming infected by consuming the milk. How these devices were designed was described, for example, in the 1903 annual report of the Pharmacie , which was published by the German Pharmacists' Association :

“The apparatus consists of a copper kettle with a capacity of around 200 liters of milk, which hangs in a water bath, but is not touched by the water itself. Its balanced lid carries a thermometer and a stirrer, which is driven by a weight motor, and there are also two ventilation openings in the lid. The water bath is heated with a weighed amount of wood, the motor is set in motion and soon the milk has reached the required 68 ° C. heated, whereupon the furnace is turned off. The heat reservoir of the water bath is to be dimensioned so that the temperature of the milk remains constant for about two hours with constant action of the stirrer. […] Finally, the milk is quickly run over a surface cooler […] from here it reaches approx. + 6 to + 4 ° C. [...] "

The following factors were identified as important prerequisites for the success of the destruction of disease-causing microorganisms at the World Dairy Congress in the United States of America in 1923:

  1. Heating to no less than 145 ° F.
  2. Maintain temperature no lower than 145 ° F. for not less than 30 minutes
  3. Cooling the milk to 50 ° F. or less immediately after the hold time

At the same time, it was warned that so-called pasteutization apparatus, which do not comply with these requirements, pose a serious risk to the health of the population. It was therefore required that such devices, which did not have suitable vats to maintain the temperature for the minimum period, should be prohibited by law.

On the basis of this knowledge, simple boiling pots were developed for domestic use , in which, on the one hand, containers could be sterilized and, on the other hand, supplies (juices, fruit, vegetables, mushrooms or meat dishes) could be preserved by boiling .

Product pasteurizers

Here the product itself is heated directly, e.g. B. Milk is heated directly by means of a tubular heat exchanger or plate heat exchanger and made durable in this way. The product is filled into the containers (tubular bags, bottles, ...) only after pasteurization.

Container pasteurizers

Here, the goods are first filled into the containers, mostly bottles. The machines are usually only long tunnels in which z. B. Beer bottles (already filled with beer and sealed) are sprayed with water while they are driven on a conveyor belt through the machine. In this way, the content (here: the beer) is brought to a higher temperature for a certain time until the required pasteurization temperature is reached.

Subspecies of pasteurizers (depending on use)

  • Electric pasteurizer - the device is heated electrically.
  • Gas or oil pasteurizer - gas or oil is used for heating.
  • Plate pasteurizer - a device that has a plate heat exchanger . Suitable, for example, for the heat treatment of milk, raw eggs, margarine, beer, wine or juices.
  • Tube pasteurizer - a device that has a tube heat exchanger (tube-in-tube heat exchanger). The material to be pasteurized and the heating fluid are fed together through a double pipe.
  • Tunnel pasteurizer or tunnel pasteurizer - a tunnel through which the already filled and sealed goods (drinks, canned food ...) are passed and sprinkled or sprinkled with water. In this way, carbonated products can also be pasteurized.

literature

  • Heinrich Schönfeld, A. Westerink-Schaeffer: The production of margarine . In: Chemistry and Technology of Fats and Fat Products . tape 2 : Processing and application of fats . Springer-Verlag, Vienna 1937, p. 739–823, here p. 787 , doi : 10.1007 / 978-3-7091-5412-0 ( books.google.de - reprint, therein Der Plattenpasteur ).

Web links

Individual evidence

  1. ↑ RÖMPP Lexicon Biotechnology and Genetic Engineering . 2nd Edition. Georg Thieme Verlag, 1999, p. 587 ( books.google.de - excerpt).
  2. ↑ A practical pastutizing device for children's milk . In: Annual report on the progress of pharmacognosy, pharmacy and… 38th year 1903. Vandenhoeck & Ruprecht, Göttingen 1905, p. 146–147 ( Textarchiv - Internet Archive ).
  3. ↑ Samuel M. Heulings: Temperature- retaining vats for the pasteurization process . In: United States Department of Agriculture (Ed.): World Dairy Congress, 1923. Excerpt . New York 1923, Abstract No. 198 ( Textarchiv - Internet Archive ).