In the beer brewing process, besides the technical method, the most important thing is the cleaning problem. The brewing, conditioning and storage of beer takes place in large stainless steel tanks that must be cleaned frequently, and the quality of the beer cannot be guaranteed if the cleaning is not done well.
Microorganisms exist stably in the environment and equipment of factories. We’re not just talking about microbes in the environment, but also those introduced with raw materials: grains, grapes, molasses, etc. all have natural microbes. Fortunately, due to the high temperature and ethanol concentration, pathogenic microorganisms cannot survive the production phase. However, they can have a serious impact on the quality of our products.
Talking about CIP systems must mention bacteria. Many bacteria survive and thrive during the raw material handling and fermentation stages, principally lactic acid bacteria (LAB), especially Lactobacillus (rod) and Pediococcus (round).
In the production of certain spirits (whiskey, rum), the presence of lactic acid bacteria is essential for the development of certain flavors, but an excess of lactic acid bacteria can lead to a lower pH during fermentation, which in turn leads to slower or hindered, resulting in reduced yields and bad odors.
By “wild yeast” we mean any yeast that has not been intentionally inoculated into the fermentation medium. This can also include other yeast strains used in other processes.
These different yeasts can cause:
Produces different aromas during fermentation
have different fermentation yields
Interfering with and inhibiting the actual fermentation process
Fortunately, we don’t need to wipe out all microbes. We can simply reduce their number to a level commensurate with process efficiency and product quality, and keep that level steady.
The purpose of cleaning is not only to remove microorganisms, but also to remove any available sources of nutrients in equipment and piping.
Brewery CIP cleaning process
In the past, the traditional cleaning method required dismantling the pipe, cleaning it by hand with a brush, and then washing away the dirt with water. This cleaning method is labor-intensive, time-consuming and difficult to achieve aseptic requirements. At present, the domestic large, medium and small breweries generally adopt the CPI in-situ cleaning method. Its advantage is that it does not need to disassemble the pipeline and equipment, and the cleaning liquid is connected with the equipment and pipeline to be cleaned to form a closed system. Circular cleaning replaces manual operation, and makes the entire cleaning process transition to automation and program control, and the cleaning effect has leapfrog development compared with the past. At the same time, since people do not need to enter the container, it is also easy to achieve sterility.
CIP cleaning system is generally used to clean tanks and pipelines. According to different requirements of manufacturers, it can be equipped with hot water tanks, alkaline water tanks, acid tanks, disinfectant tanks, etc. The tank body is usually made of austenitic stainless steel with corrosion resistant alloys such as AISI 304, 316 or 316L, weld seams with polished tape. Today’s CIP cleaning system is also more and more automated, and can fully automatically control temperature, liquid level, concentration, and flow.
The cleaning sequence for a brewery CIP system consists of multiple steps including a pre-rinse with water, circulation of acid and/or alkaline cleaning solutions, further rinses with water between cleaning cycles, circulation of a sanitizing solution, a final rinse with fresh water, and in some cases The following ends with a drying cycle.
Effectiveness of the CIP system
Depends on four factors: mechanical action, chemical action, temperature, and cleaning-in-place time.
Physical removal of contaminants through the action of pressure or the creation of turbulent flow. With increased mechanical action, cleaning becomes more effective and faster. In distillation, winemaking and beer making, flushing is accomplished by flushing cleaning fluid down the pipes at high velocity and using high pressure cleaning nozzles in the tanks.
The type, formulation and concentration of cleaning chemicals are important. Detergents can be more effective if added with compounds that increase wetting and chelation (that is, the ability to bind metal ions that can cause fouling).
Excessive temperatures may cause decomposition and precipitation of dissolved solids. Using the correct temperature for your detergent maximizes its effectiveness.
Time is often the most precious resource and production time must be maximized. Therefore, shortening the time of the fast cleaning cycle is usually compensated for by increasing the influence of the other three factors of the CIP system.
Notes on the selection of CIP system
Centralized installation vs. distributed installation: First of all, the scale of the factory must be considered, which equipment or brewing process needs to be cleaned by the CIP system, the capacity of the equipment to be cleaned and the total capacity. In order to determine the choice of the size of the CIP system. Second, it is necessary to evaluate the management and economic benefits of a single centralized CIP station. Alternatively, multiple smaller CIP stations can be purchased and placed near the equipment to be cleaned.
Single-Use CIP vs. Recycling CIP: In a single-use solution, the cleaning and rinsing solutions are not recovered, recycled and reused as in a multi-use solution.
In more complex cases, tools such as 3D modeling and CFD (computational fluid dynamics) studies can help understand the impact of CIP on pipeline and equipment cleanliness.