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.
Filtration Before Finished Product Filling: The “Final Check” for Quality
Even after multiple processing steps, trace impurities may still be introduced into food and beverages before the filling process due to factors such as pipeline wear and environmental dust. If these impurities enter the finished products, they will not only affect the consumers’ drinking experience but also trigger product complaints and brand trust crises. Therefore, “terminal filtration” before finished product filling is of vital importance, and liquid filter bags are the core equipment in this link.
Taking bottled drinking water production as an example, the terminal filtration before filling usually uses sterile filter bags with a precision of 0.22-1 micron (such as polytetrafluoroethylene (PTFE) membrane filter bags). These filter bags can not only trap bacteria, microorganisms, and tiny particles in the water but also have sterilization resistance (such as steam sterilization and chemical sterilization), ensuring that the filled drinking water meets the requirements of the national standard GB 19298 “National Food Safety Standard for Packaged Drinking Water”. In the production of carbonated beverages, the terminal filtration requires the use of pressure-resistant and carbonic acid corrosion-resistant filter bags (such as polyester membrane filter bags) to prevent the filter bags from breaking due to the pressure of carbon dioxide gas, while ensuring that the filtered beverages are free of impurities and have a smooth taste.
Core Points for Selecting Liquid Filter Bags in the Food and Beverage Industry
- Material Compliance: Prioritize filter bags that comply with food contact material standards (such as FDA, EU 10/2011, and GB 4806) to prevent harmful substances in the material from migrating into food and beverages;
- Precision Adaptability: Select the appropriate filtration precision based on the characteristics of impurities in different process links (e.g., 20-50 microns for raw material pretreatment and 0.22-5 microns for terminal filtration). Avoid excessively high precision, which may lead to reduced filtration efficiency and increased costs, or excessively low precision, which cannot meet the filtration requirements;
- Hygienic Safety: For scenarios with extremely high hygiene requirements, such as dairy products and sterile beverages, sanitary-grade filter bags should be selected. These filter bags are equipped with food-grade sealing rings, and their surfaces are smooth and free of dead corners, facilitating cleaning and sterilization;
- High-Temperature and Corrosion Resistance: Choose filter bag materials with high-temperature and corrosion resistance according to the temperature (e.g., high-temperature fruit juice after pasteurization) and acidity/alkalinity (e.g., acidic beverages and alkaline syrups) of the liquid during the production process to prevent the filter bags from being damaged or degraded during use.
In conclusion, liquid filter bags in the food and beverage industry are not only “interceptors” of impurities but also “guardians” of quality. With the continuous improvement of consumers’ requirements for food and beverage safety and quality, and the continuous upgrading of industrial production processes, liquid filter bags will develop in the direction of higher efficiency, better compliance, and more customization, providing a more solid guarantee for the healthy development of the food and beverage industry.
