Jun 15, 2021
Oak stabilizes color and smooths tannins, some think of it as a
seasoning ingredient. But what about the other vessels that are
increasingly popular for fermentation and aging? What do they do
and are they really more than hype? We discuss the main
alternatives to oak -- concrete and amphora, what each does and the
benefits of each.
Photo: Concrete eggs made by Sonoma
The show is a hybrid of discussion and interview, as I welcome
Steve Rosenblatt of Sonoma Cast Stone, who
manufactures custom concrete eggs and tanks, and Debbie
Passin of VinEthos.com who sells custom, next generation
We start at the beginning and explain the purpose of all vessels
for fermentation and aging.
For winemakers looking for good texture and small transfers of
oxygen to smooth the tannins in reds and provide a good medium for
sur lie aging in whites, but who don't want the oak flavor, they
have a few choices.
- They can use aged, neutral oak barrels. These
neutral barrels provide the benefits people seek but they do absorb
a lot of wine, are hard to clean, and don't always keep the fresh
flavors of the wine.
- They can use stainless steel tanks or smaller stainless
steel drums. These are great for wines that don't need any
oxygen, as they keep flavors fresh and clean. They are temperature
controlled, easy to clean and sanitize, and they allow the wine's
flavor to shine. For those who want a more intense flavor, the
smaller vessels will allow more contact with the lees (dead yeast
cells that break up and give nutty, breads flavors to the
Photo: Quality Stainless
But what if you want the benefits of oak without the flavor?
That's where concrete eggs and amphoras come in.
We first address concrete, which is at this time, a bit more
popular than amphora. The main benefits we discuss:
- The shape of the egg allows for continuous flow to the
wine as it ferments and matures, creating a more homogenous
- As fermentation creates heat, convection currents move the wine
around, as it does in a tank or barrel. The currents are so strong,
that the wine barely needs to be punched down or pumped over during
fermentation. Battonage (stirring lees for increased flavor) also
is barely needed. The lack of corners in the container mean there
are no "dead areas" and the wine is more complex and uniform in
quality and texture.
- Tannins are softened during maturation: Similar to the benefits
during fermentation, the egg shape constantly circulates the lees
as the wine matures after malolactic fermentation so the tannins in
reds are softer and finer with age in eggs.
- Insulation: Concrete can be up to six inches
thick so there is natural insulation from outside temperature
swings that stainless steel tanks cannot provide without cooling or
heating coils. This allows wine from concrete eggs to maintain
- Oxygenation (with a caveat): Unlined concrete
allows tiny amounts of oxygen to permeate and come into contact
with the wine (from inside of the tank when it first is put in the
tank). This softens tannins, creates complexity, texture, and a
better mouthfeel especially during fermentation. The wine is fruity
without any oak flavors.
- Beauty and sustainability: The vessels are
beautiful, can be customized, and they last forever if they are
taken care of – score for sustainability!
- Ease of cleaning in a fermentation or aging
vessel is really essential in wine. Sanitized vessels = clean wine.
Concrete is easy to sanitize and clean.
Rosenblatt, Sonoma Cast Stone
After we set up the history and benefits of concrete, I welcome the
wonderful Steve Rosenblatt, founder and owner of Sonoma Cast Stone (and hobbyist winemaker!), the
only manufacturer of concrete eggs in the United States, who gives
us incredible detail on these benefits and more.
Next, we discuss amphoras. The benefits are
largely the same (shape allows convection, clay is great for
insulation, they are beautiful and sustainable, and easy to clean)
but the real difference is porosity of amphoras, which mimics oak
without flavor more than concrete…
- True mico-oxygenation...Amphoras are made of
clay and the newest generation have materials that can be fired at
very high temperatures (in a kiln). These new amphoras don’t impart
flavor, don’t crack or leak, and they have small pores, which allow
for slow and steady micro-oxygenation similar to oak. The wine has
complex texture, tannins relax over time, and lees are integrated
into the wine. The difference: the grape and terroir are preserved
with no oaky flavor.
Photo: Deborah Passin of
Deborah Passin of VinEthos, who sells the top
amphora producer, helps explain amphora and, importantly, dispel
the myth that somehow amphora are only for natural wine or for
funky, oxidized styles. Amphoras are great vessels for all
I learned so much in this show – I hope you will too!
Thanks to our sponsors:
Thanks to YOU! The podcast supporters
on Patreon, who are helping us to make the podcast
possible and who we give goodies in return for their help! Check it
Visit: www.wineaccess.com/normal and for a limited
time get $20 off your first order of $50 or more!
Access is a web site that has exclusive wines that
overdeliver for the price (of which they have a range).
- They offer top quality wines by selecting diverse, interesting,
quality bottles you may not have access to at local shops.
- Wine Access provides extensive tasting
notes, stories about the wine and a really cool bottle hanger with
pairings, flavor profile, and serving temps.