In the food and beverage industry, “safety” and “quality” are core keywords throughout the entire production process. Liquid filtration, as a crucial link in the production chain, directly determines the purity and taste of the final products. Liquid filter bags, with their high-efficiency filtration performance, compliant material selection, and flexible adaptability, have become indispensable filtration equipment in this industry. From raw material processing to finished product filling, they provide protection for every drop of beverage and every portion of food.
1. Raw Material Pretreatment: Blocking Impurity Contamination from the Source
The starting point of food and beverage production often involves various liquid raw materials, such as drinking water, fruit juice concentrate, syrup, and brewing liquor. These raw materials may contain impurities that are invisible to the naked eye—sand and sediment in water, microbial residues, pulp debris and pectin particles in fruit juice, and crystalline impurities in syrup. If not filtered in a timely manner, these impurities will not only affect the taste of the products but also clog subsequent production equipment (such as pipelines, pumps, and filling valves), and even pose a risk of microbial growth.
Liquid filter bags play the role of the “first line of defense” in this process. Based on the characteristics of different raw materials, the industry usually adopts food-grade polypropylene (PP) filter bags or polyester (PET) filter bags. These materials not only comply with international food contact material standards such as FDA (U.S. Food and Drug Administration) and EU 10/2011 but also possess acid and alkali resistance and high-temperature resistance (some models can withstand temperatures above 120°C). They are suitable for scenarios such as filtration of fruit juice before pasteurization and clarification of syrup after heating and dissolution. For example, in fruit juice production, the use of filter bags with a precision of 5-20 microns can effectively trap pulp fibers and colloidal particles, giving the fruit juice a clear and transparent appearance. At the same time, it prevents impurities from adhering to the tube wall of the evaporator in the subsequent concentration process, thereby improving the heat exchange efficiency of the equipment.
2. Production Process Purification: Ensuring Process Stability and Product Consistency
In the intensive processing link of food and beverage production, the application of liquid filter bags is more segmented, requiring precise matching of filtration precision and material according to specific process requirements. Taking beer brewing as an example, the fermented beer contains impurities such as yeast cells and protein precipitates. Direct filling without filtration will cause turbidity and sediment in the beer, affecting its shelf life and drinking experience. At this point, the use of beer-specific filter bags (usually polypropylene membrane filter bags with a precision of 1-5 microns) can efficiently remove suspended impurities without damaging the flavor substances of the beer, maintaining the stable clarity of the beer and extending its shelf life.
The application of liquid filter bags is also crucial in dairy production. For instance, in the pretreatment of raw milk before yogurt fermentation, filtration is required to remove mechanical impurities and whey protein clots from the raw milk, preventing these impurities from affecting the activity of fermentation strains and the texture of the yogurt. At this stage, the selection of sanitary-grade polypropylene filter bags (equipped with food-grade sealing rings and complying with 3-A Sanitary Standards) not only achieves efficient filtration but also meets the strict requirements of dairy production for equipment cleanliness, preventing cross-contamination.
