There is a snobbery about using polypropylene tanks in a winery. We have a romantic vision of oak vats and barrels lining the walls of old world caves or of massive shiny stainless steel tanks lining up like obedient soldiers in an echoing industrial chamber. Either way, this media-encouraged image is not true to most winery practices. I have to admit, that a few years back I danced around the use of poly-tanks for fermentations and most especially the use of plastic for blending and holding wine for short periods of time. But last year I outed my own love of plastic…yes, I like poly! Here’s why;
Polypropylene tanks, especially in the form of IBC totes, are cheap, readily available, easy to clean, easy to stack and store. They also breath well and reduce reduction in wine and seem to hold in volatile fermentation aromas on whites. Plus, I can pallet jack around a full tank by myself, a big plus for a woman working alone in the winery.
I am not alone in the use and love of polypropylene tanks. Most wineries use totes for various reasons, and many others use plastic tanks exclusively. Most wineries use plastic tanks for the same reasons I do, and most are part of an oak and stainless program as well. I don’t use stainless steel tanks, so my program is entirely plastic and oak.
So what does the vessel have to do with the style of wine produced?
Surprisingly, the choice of tank or vessel has a huge impact on the style of wine produced. We all know the impact of maturing red wine in oak barrels. But most wineries use other storage for white wines and some reds. The choices are few; stainless steel, polypropylene or concrete. Each of these choices imparts a particular style to the wine.
Although concrete would certainly be my first choice for style, I use poly tanks for the roundness that it imparts in wine. I am almost certain that this feeling of softness comes from oxygen pick up, but I have not found any conclusive study on sensory analysis of wines stored in poly tanks to corroborate my assumptions. Because my whites do not undergo malolactic fermentation to soften acids, and I really like high acid whites, I strive for a softness that is difficult to create in an acidic wine. Plastic and concrete seem to do this well, while I feel that stainless steel accentuates the harshness of high acid wines.
What are the caveats of using polypropylene?
The obvious caveats for using poly tanks is that they are a petroleum product. The environmental impact for producing these tanks is huge! Choosing to use a plastic product produced from an industry with a terrible history of environmental stewardship is a tough one for me. However, a comparison of the alternatives offers no better solutions with the exception of concrete. Concrete tanks are certainly in the future of AniChe Cellars, but the extreme cost of concrete tanks is currently prohibitive.
Does polypropylene have a health impact?
I get this question a lot. There are no BPA’s in polypropylene. It is an FDA approved material for food grade storage. However, the FDA has approved many forms of plastics that have questionable health impacts. Other chemical leaching can occur with plastics, and although I have searched high and low for a real scientific study on polypropylene leaching and have come up dry, I am still quite skeptical. Therefore, I purchase my IBC totes from a recycling operation that only purchases totes that have transferred neutral spirits like vodka from Europe. If there is any leaching to be done, it will certainly have taken place in it’s first use!
Is polypropylene sustainable?
Choosing materials to work with in a winery is not easy for a conscientious winery. When I wrote my first business plan in 2008, I researched the sustainability of our winery extensively, and found that a winery can be focused on sustainable practices but cannot be entirely without environmental impact. Polypropylene is not sustainable, of course. The only way that I can justify using this material is by carefully selecting high quality recycled tanks from conscientious vendors. However, these bottles can last years and years with care. At the end of their lives they can be recycled.