7/26/2019 Pasteurization Unit

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pasteurization unit

One pasteurization unit is the microorganism death that occurs in a product held at 60C for 1

minute. It was defined in 1951 b !el "ecchio et al#$ and is emploed in rating the effecti%enessof pasteurization processes for beer and other products. &mbol# '(.

)he number of '(*s re+uired for a particular be%erage depends on se%eral factors# such as the

microrganisms it contains and e%en on the tpe of pac,aging. -ild/ easts# for eample# such

as occur in some tpes of elgian ales# are more resistant to heat than domestic easts. 2 sur%eof large 2merican breweries in 1955 found their processes a%eraged 13.4 '(*s# wih a range of

.3 to 35.6 '(*s.

)he success of pasteurization that is# what percentage of the microrganisms are ,illed7 is

affected b both temperature and b the length of time for which the product is held at that

temperature. It is a tradeoff8 high temperatures for short times or lower temperatures for longertimes. (nfortunatel# higher temperatures tend to affect the taste of the be%erage.

)he total number of '(*s for a particular pasteurization processs for beer can be estimated from8

'( : t ; 1.