Food and beverage: Filters keep the wine flowing

2 min read
The wine production process.
The wine production process.

The Changyu Group Company Limited is one of the biggest and oldest producers of wine in China. The company has plants throughout China, including Shandong, Beijing, Xinjiang, Ningxia and Shaanxi. Changyu produces 350,000 tonnes of wine per year, including dry red, dry white and brandy among others. The wines are well regarded and sold throughout China and around the world. Every wine has a unique character that needs to be preserved and protected. Filtration plays a vital role in this, through the removal of fermentation by-products and microbes that could cause spoilage. In addition, the filtration process cannot change the flavour, aroma and colour characteristics that make the wine special and unique. Changyu Group Company Limited has relied on Hangzhou Anow Microfiltration Co. Ltd. To solve many of its filtration problems, Anow has supplied a range of products that cover pre-filtration and final filtration products. In wine production, the filtration system usually comprises both classification filtration and sterile filtration. The basic principle for the filtration is from coarse to fine. This entails larger particle retention first, followed by smaller ones later, in a series of steps. This has the advantage of extending the service life of filters, as well as obtaining good filtration at a lower cost. Consequently, a number of different filters are required that vary in materials and the pore sizes of the filter membrane. The filtration system in wine production has to meet a number of separation goals. These include removal of yeast and other fermentation by-products before bottling. In addition, it is essential to prevent microorganisms from entering the storage tanks, as well as ensuring microbial stabilisation. Finally, it is necessary to remove particulates and microbes from bottle rinse water and utility water. In order to meet these goals, filters must be able to provide high flow rates and be sufficiently robust to meet the demands of the mass manufacturing process. The final filtration stage must also able to maintain reliable retention of microorganisms for a significant period of time. In addition, filters must have no adsorption or binding with preservatives during product manufacturing. The filtration steps start with the clarification stage to remove particulates and colloids. Anow recommends its LFP-PP (polypropylene) and LFPF-Multi layer PP filters for these applications. The LFP-PP offers good dirt holding capacity and high flow rates, as well as broad chemical compatibility. It also offers low extractables and low protein binding. In addition to these qualities, the LFPF can also offer long service life and reliable retention of particulates. It is also said to be ideal for viscous and colloidal liquid filtration. The pre-filtration stage requires cost-effective filtration for colloids and viscous liquids. LFP and LFPF filters are also used at this stage. In addition, the LFGF-Glass fibre filter can also be employed in pre-filtration. It offers high throughputs and high adsorption, as well as good dirt holding capacity. High flow rates are achieved at low pressure drops. Cost-effective with long service life, it also has reliable retention of particulates. For the final filtration stage, the LFS-A asymmetrical hydrophilic PES membrane is recommended. It offers broad chemical compatibility, good heat resistance, low absorption and an absolute retention of particles and microbes. This is key for maintaining the stability and safety of the wine. High throughputs and long service life are achieved. Finally, for sterile venting the LFTA hydrophobic PTFE membrane can be employed. Its advantages include high flow rates and low pressure drop, as well as having high strength, long service life, and being cost-effective. Constructed of oxidation-resistant materials, the LFTA filter offers a particulate removal rating of 0.01μm in gases for vent applications. Hangzhou Anow Microfiltration Co. Ltd. adds that its filters have been employed in wine production for many years and the company is currently working on further improvements in higher flow rates and longer service life.