Sunday, May 24, 2009

My White Grenache is Hazy


The top picture is the 2008 White Grenache after bottling it, and about 6 weeks of storage. The bottles all have a a white sediment. If I decant off the sediment, then the bottle develops more haziness, which gradually settles.

The lower picture is the wine as it came out of the demijohn - and it was nice and clear. It also had a phenolic taste that disappeared after bottling.

Anyway, I think there has been some oxidation or acidification that has altered the flavor and knocked something out of solution.

The wine books have several more or less practical ways to clarify wine, like gelatin or egg white. 















I am tempted to dump up the bottles into a container, add sulfite, and let it settle by itself. After some length of time, I would filter it. 

My problem is that I don't have a five gallon container that is suitable, and the wine may spontaneously start precipitating something. 


Sunday, May 17, 2009

Wine Flavors Introduced by Oak Aging



I am thinking about whether to treat my 2008 Merlot with oak chips, and I was interested to see this article on what chemicals are found in oak chips. To my surprise most of them have some sort of desirable flavor, with the notable exception of the trichloroanisole. I am surprised that there are trichloro compounds in wood at all. This one does not seem to have severe safety issues, but I understand it has the Champagne producers concerned about adulteration via wine corks.

Fernández de Simón and others have published the work of GC/MS work on several species of wood that are commonly used to store food and impart flavor to them. They made a lengthy list in J Agric. Food Chem 57:8 (2009). I have extracted out the most important components from American Oak that has been "toasted." There are several other wood species in the work. 

People should not be surprised to learn that wine scholars have been researching these extractives for years, and there is a lot published on them. 

The graph at right shows the relative proportions of the top ten extractives. There are many more. 

2,4,6-trichloroanisole (100 ppm)- This is the compound responsible for cork taint, and it ruins the flavor of wine even at nanogram/L levels. Smells like moldy newspaper

syringaldehyde(226 ppm), coniferaldehyde (96 ppm), sinapaldehyde (239 ppm) - vanilla related aldehydes

butyrovanillione (113 ppm) = zingerone = vanillyl acetone - also found in ginger; medicinal uses

Whiskey lactone (beta-methyl-gamma-octalactone) (32 ppm)- One of the main components of aroma in whiskey

Furfural (395 ppm) - almond-like, sometime describes as burnt; increases with the "toasting" of the oak wood

5-methyl furfural (34 ppm)- spicy, carmel-like, sweet

Saturday, May 9, 2009

Racking the 2008 Merlot

I racked the Merlot today, and I was pleased at how much it had matured. There was only a small amount of sediment, which I washed out.

Based on my brother, Glenn's advice I am going to wait until fall to bottle this. In the fall, I will need the bottle.

The Merlot now tastes like Merlot with fruitiness, but also with a stringency and hardiness. It is not as fruity as Shiraz. It is not a very complex flavor though, still relatively simple. It is nice, and quite drinkable especially with food.

Of course, I don't believe that good wine should be drunk with food, since the food wrecks the flavor of the wine. Good wine should be enjoyed alone.

As mentioned below, the fermentation carboy is a reducing environment, and by racking it we let is oxidize a bit. Unlike the 2008 White Grenache, there is no bitterness.

I have not added any oak chips, which I contend are unwelcome to my palate. I did put a three tea bags in during the winter to get the tannins up. I think tea tannins are nicer than oak tannins.