In the production process of beer, every step from the input of raw materials to the output of finished products is of vital importance. The Pass Boxes in a brewery, serving as crucial channels for the transfer of materials between different areas, have extremely “stringent” cleanliness requirements.

Firstly, considering the raw material stage. The main raw materials for beer include malt, hops, yeast, and water, etc. These raw materials need to undergo strict inspection and processing before entering the production area. As one of the entrances for raw materials to enter the production area, the Pass Box must maintain a high level of cleanliness. If there are pollutants such as dust and impurities inside the Pass Box, they are likely to mix into the raw materials, affecting the quality of the beer. For example, the microorganisms in the dust may compete with the yeast for nutrients during the fermentation process, resulting in abnormal fermentation and affecting the flavor and taste of the beer.

During the production process, different areas of the brewery have varying cleanliness requirements. For instance, the brewing area needs to prevent contamination by external microorganisms to ensure the normal fermentation of the beer; the filling area requires a highly clean environment to avoid the beer from being contaminated during the filling process. As a channel connecting different areas, the Pass Box should play the role of isolation and purification. It needs to have good sealing performance to prevent external air and pollutants from entering. At the same time, the interior of the Pass Box needs to be cleaned and disinfected regularly to ensure the cleanliness of its internal environment.

When the beer reaches the finished product stage, the cleanliness of the Pass Box cannot be ignored either. If the cleanliness of the Pass Box fails to meet the standards during the transfer of the finished beer, it may lead to secondary contamination of the beer. For example, the bacteria inside the Pass Box may breed on the surface of the beer bottles, affecting the hygienic quality of the beer.

So, what are the specific "stringent" cleanliness requirements for the Pass Boxes in a brewery? In terms of hardware facilities, the materials of the Pass Boxes need to be corrosion-resistant and easy to clean, such as stainless steel. This can facilitate daily cleaning and maintenance and prevent the growth of bacteria on the surface of the materials. In terms of sterilization, the Pass Boxes need to be equipped with ultraviolet germicidal lamps, which can disinfect the air, object surfaces, etc., effectively kill a variety of harmful microorganisms such as Escherichia coli, Staphylococcus aureus, and influenza viruses, reduce the risk of infection, and ensure the hygiene and safety of the environment and items. At the same time, the air flow inside the Pass Boxes needs to be reasonably designed to avoid the formation of air stagnation areas, so as to ensure the uniformity and cleanliness of the internal air.

In addition, there are strict regulations for the use and management of the Pass Box. Operators must strictly follow the operation procedures for cleaning and disinfection before and after using the Pass Box. The opening and closing time of the Pass Box also needs to be strictly controlled to reduce the entry of external air.

In conclusion, from raw materials to finished products, the cleanliness requirements of the Pass Boxes in a brewery run through the entire production process. These “stringent” requirements are all aimed at ensuring the quality and hygienic safety of the beer. Only by strictly controlling the cleanliness of the Pass Boxes can high-quality beer be brewed to meet the needs of consumers.