Filtration technologies: a review

Our very own Paul Baggio examines how the adoption of new filtration technologies can lead not only to greater efficiencies for winemakers but can also earn wineries kudos from environmentally and socially conscious consumers.

The latest cohort of new entrant wine drinkers, defined as Gen Z and Millennial aged consumers, are making retail bottle purchase decisions - and are in fact making a whole range of broad-based life, investment and employment decisions - influenced by perceptions of how products, brands and businesses behave environmentally and socially. The latest generation of consumers are forging very firm environmental, social and corporate governance beliefs and are redefining consumerism in very unique and influential ways. Product satisfaction and consumer loyalty is being exchanged for alignment to their range of core social and community values. These new-aged consumers are growing their consumption of wine and attracting higher margined price points. In a market experiencing declines of traditional consumption per capita rates, the industry could well look towards courting such new entrants. Winery design and vinification processes can be re-worked using available technologies to bring real-time ESG kudos. Delivering a manufacturing footprint that brings an elevated respect for its consumer's environmental and social aspirations is financially feasible and accessible. In this discussion piece we look to explore the winemaking and packaging technologies, in particular filtration and clarification technologies, that will deliver genuine sustainable processing and manufacturing practices.

OMflow by Omnia Technologies Group

At the ground level of most wineries, the front-end practices of vinification are not very glamorous. For those of us having worked RDV/RVFs (rotary drum vacuum filters) would well attest. Yet the traditional processes of juice clarification, settling juice extracted from presses to settle out phenolic substances and browning fractions in white wines, the process is as notoriously environmentally unfriendly as it can be. Crush cooling juices for some 24-hour timeframes to between 2-4°C in winery environments having ambient harvest temperatures of 30-35° C takes some significant kWs to achieve. Yet juice floatation in either continuous or static forms has been a technology that has been accessible to winemakers for decades. The process involves nitrogen and/or oxygen being sheered into microscopic sized bubbles and injected into a pool of grape juice, affecting solids suspended at ambient temperatures forming a high solids (flees) cap, with clarified grape juice to be 'racked under float'. The ability for juice filtrate to exit at winemaker filtrate specifications of 150-250 or 350 NTU at speeds of 5000lts/hr or 10,000lts to 120,000/180,000lts per hour is a very real accessible technology. That these systems also function at high efficacy using plant-based clarification agents, and not reliant on bovine or other cow/ pig intensity farming, provides a further synergy with modern ethical viewpoints surrounding best agriculture practices, veganism and reduced methane to name a few. That refrigeration dependency can be dramatically reduced for a broad range of high energy, high carbon loaded processes is critical for our industry to consider. Continuous floatation enables more effective solids handling processes than traditional juice cold settling creates. The consolidation of juice lees via cold settling of tanks creates a range of labour work practices what for many wineries are problematic. It is often the case cellar persons are required to 'dig' out wine tanks, or tanks needing to be 'jetted' requiring significant energy use to mobilise solids. The mechanical action by which continuous floatation mobilises high concentrated solid volumes to down-stream separation technologies provides wineries a more fluid management, thus avoiding the need for labour to actively access solids handling manually.

Transitioning to cleaner, more sustainable options

The downstream processing of juice solids, the process of recovering juice from lees, has long been a dirty, ecologically problematic winery process. Apart from the filter media utilised to pre-coat RVF/RDV filters being a highly hazardous product, classified as a carcinogen, there's also the extortionate volumes of water waste required for using rotary vacuum drum systems. it stands to reason that most wineries should have long dispensed of rotary vacuum filters many years ago. That highly effective high solids juice cross flow (HSXF) systems such as the Dynamos or Della Toffola Omnia, each designed with ceramic wide bore membranes, have been successfully operating in our current wine industry for well past a decade now suggests the practice of importing the millions of tons of perlite and/or diatomaceous earths that our industries do needs a rethink. The cost of logistics, storage and application of these problematic filter medias is itself making the case that to transition to clean, more sustainable filter media, such as ceramics, is a highly viable option. The ability for wide bore HSXF (high solids cross flow) systems to take, at the inlet, juice solids concentrates of 30%-40% by volume and process them to an 80%- 85% volume over the long run, while operating autonomously, provides a solution that fits with the modern social and environment value system. That the Padovan and Della Toffola systems are each ceramic and not made from a plastic polymeric form, further provides a strong environmental message of sustainable winery practices. This similar technology is being deployed to process wine lees, thus recovering efficiencies from wine tanks, enabling wines to be made more stable, and more readily and effectively without the hard­ line refrigeration cold crush cooling of the winemaking past. The savings to energy are significant; yet the fact that no filter earth media are required makes the case for ceramic membrane cross flow systems even more powerful.

Della Toffola continuous flotation and high solids filtration

Wine stability can be positively affected by inline continuous tartrate systems, such as CTS that utilise a fraction of the energy and water consumption of the traditional contact and hold systems, at a time where energy costs are soaring and accessing energy in many wine regions problematic. The process of wine contact and hold stabilisation is one of the most energy hungry vinification processes for white wine production in the winery. Similar to RVF, traditional contact and hold wine stabilisation is a winery practice that should be looked at to be made redundant. Accessing more a modern CTS system along with using continuous floatation both provide the opportunity Australian and New Zealand winemakers to cut winery energy use by well over a half. The major area for which environmental and winery social governance matters can be most positively impacted in winemaking countries like Australia and New Zealand is through changing how wines are packaged for export. Australia's wine consumption is split with approximately 40% of wines consumed locally and the balance exported to a range of markets such as the UK, Europe, Asia and the USA. For New Zealand the proportion of its manufactured volumes are predominantly destined for exports.

Much of the dry goods used in wine packaging are imported, such as glass bottles and caps for example, with these freighted considerable distances. This is a significant environment impost it can be argued for our wines compared to our competitors' wines produced in the country of origin in which they are consumed. Our wines exported to Europe are being carbon rated as having some of the highest carbon footprints in the world. Our younger wine consumer (the highly-prized wine drinkers located in the UK or northern Europe for example) would find our lack of decarbonised footprint concerning. This should not be ignored. Many progressive local winemakers are opting to freight wine in a bulk (not bottled) format to European and Asian markets, side-stepping the costly process of importing empty glass and dry goods, and are freighting their wines in bulk via shipping containers, bottling and packaging these in the target foreign market. The technologies of two-stage and/or three-stage high-speed lenticular sterile membrane filtration systems such as OMFlow technology is the most effective system to deliver inline sterile gas feed along with sterile wines into a large format container ISO tank or bulk container bag.

Our wine industry has the need for some radical process change at the winery level and innovative technologies are available to meet the challenges. The latest consumption and retail wine spend data is showing Generation Z and Millennial consumers are bringing their sought-after attention to our wines and brands. Yet they are bringing with this the ire of their judgment and their value-based system of decision making. Along with the threats of not being able to bring on board this prized consumer are the many opportunities.

For more info on our range of filtration technologies and solutions please contact us HERE