The place for all things wine, focused on serious wine discussions.

Geology, Nitrogen & Winemaking

Moderators: Jenise, Robin Garr, David M. Bueker

no avatar
User

Alan Uchrinscko

Rank

Ultra geek

Posts

148

Joined

Wed Mar 29, 2006 12:10 am

Geology, Nitrogen & Winemaking

by Alan Uchrinscko » Sat Apr 29, 2006 7:14 am

Anyone want to take a stab at this one:

"Soil organic content has a marked positive effect on the nitrogen content of the must, and hence on wine style"...
http://www.wynboer.co.za/recentarticles/1200geology.php3

What effect does Nitrogen have on wine style?
Alan Uchrinscko
no avatar
User

Howie Hart

Rank

The Hart of Buffalo

Posts

6389

Joined

Thu Mar 23, 2006 4:13 pm

Location

Niagara Falls, NY

Re: Geology, Nitrogen & Winemaking

by Howie Hart » Sat Apr 29, 2006 8:24 am

The only thing I can think of is the amount of nitrogen compounds present in the must effect the yeast. For example, in '04, I made a Cab Franc from grapes grown in the Niagara Peninsula and I used a yeast strain that required a high amount of nitrogen. I was supposed to supplement the nitrogen content by using yeast nutrient, but failed to do so, as I was unfamiliar with the yeast strain recommended to me. As a result, the yeast, being nitrogen starved, went through a reduction reaction and produced mercaptans, very foul smelling aromatics. I have no idea how this relates to geology, but there is a connection between nitrogen and winemaking. Perhaps the same grapes from a different terroir would have had enough nitrogen, but adding the yeast nutrient or using a less nitrogen dependent yeast strain would have also solved my problem.
no avatar
User

Thomas

Rank

Senior Flamethrower

Posts

3768

Joined

Wed Mar 22, 2006 4:23 pm

Re: Geology, Nitrogen & Winemaking

by Thomas » Sat Apr 29, 2006 8:42 am

Howie is dead right.

The proper level of nitrogen in the soil is crucial to the nutrition of the grapes. Poor nutrition can lead to bad fermentations. In fact, hydrogen sulfide and mercaptan can often be traced to poor nitrogen levels in the must.
Thomas P
no avatar
User

Alan Uchrinscko

Rank

Ultra geek

Posts

148

Joined

Wed Mar 29, 2006 12:10 am

Re: Geology, Nitrogen & Winemaking

by Alan Uchrinscko » Sun Apr 30, 2006 12:43 am

Thanks everyone for your insightful responses.

John,

I've seen the yellow leaves many times but I never knew esactly what caused them...

Alan
Alan Uchrinscko

Who is online

Users browsing this forum: Majestic-12 [Bot] and 3 guests

Powered by phpBB ® | phpBB3 Style by KomiDesign