When it comes to pasteurization, everyone must be familiar with it. Vacuum-packed meat, canned food, milk, etc. that we usually eat all use this sterilization method. Also to this, it can also be used in the fermentation industry, such as craft beer. Then let’s learn about the application of pasteurization in the craft beer industry.
Principles of pasteurization
First of all, we need to know what pasteurization is. Pasteurization is also called low-temperature disinfection, a cold sterilization method invented by French microbiologist Pasteur. It is a disinfection method that uses a lower temperature to kill germs and keep the flavor of nutrients in the article unchanged. It is a heat treatment method that is used to kill various pathogens. The heat treatment degree of pasteurization is low. Generally, food is heat treated at a temperature lower than the boiling point of water (60-82°C) within a specified time, and the medium is hot water.
Application of Pasteurization in Brewing Industry
Pasteurization solves the problems of rancidity and long-term preservation of low-alcohol wines such as wine and beer. At that time, the French winemaking industry was facing a very troublesome problem, that is, the wine would become sour after being brewed, making it undrinkable at all, and this sourness phenomenon often occurred.
Pasteur was invited to study this question. After a long period of observation, he found that the culprit that made wine sour was Lactobacillus. Nutritious wine is a paradise for Lactobacillus to grow. If a simple boiling method is adopted, the Lactobacillus can be killed, but in this way, the wine loses its original style and flavor.
At that time, Pasteur tried to use different temperatures to kill lactobacilli without destroying the wine itself; the final result of Pasteur’s research was that the lactobacilli in the wine could be killed by holding the wine at 63.5°C for half an hour. , without boiling. This method saved the French wine industry and shocked the world.
Application of pasteurization in craft beer industry
Pasteur found that the sterilization temperature used in beer is generally 60~62℃, and the time is 10~20min. Based on the sterilization temperature of 50″C, for every 7″C increase in temperature, the sterilization time can be shortened by 9/10. That is, under the same sterilization time, for every 7″C increase in temperature, the sterilization unit will increase 10 times.
Most of the bottled beer and canned beer on the market, especially the exported beer, are pasteurized to be stored and transported at room temperature.
First, let’s take a look at the pasteurization unit. Pasteurization unit means that the sterilization effect obtained by keeping beer at 60°C for 1 minute is 1 PU value: measuring the PU value can control the sterilization of beer. PU=1.393 (sterilization temperature -60℃) x sterilization time (minutes). In laboratory sterilization tests, the amount should be small and uniform. The yeast lethality value is generally 5-6 PU to achieve good results. But, it is difficult to achieve uniform sterilization in large-scale production. The least PU value in practical experience is 13.7; for safety, The pasteurization unit of beer is generally controlled between 15~25PU.
Of course, the smaller the pasteurization unit used, the better it is for the taste of beer; but, for the sake of product safety, most breweries usually control the PU value near the upper limit. Glass bottle filling is generally controlled at 20-25PU, and can filling is generally controlled at around 15PU.
The beer equipment that now applies pasteurization technology includes constant temperature water bath sterilization tanks, hot water circulating spray sterilization kettles, and tunnel sterilizers. The technologies are all mature and can be used with confidence.
Get a turnkey solution for brewery equipment
If you plan to open or expand the brewery, you can contact Micet Craft directly. Our engineers will design and manufacture brewery equipment according to your brewing process. Of course, we will also provide you with a complete turnkey solution. Also, if you plan to expand the brewery, we will provide you with customized solutions.