"It is still in its infancy and there is so much we need to learn – and Europe is where we need to look."
So said Sam Harrop MW at the recent NZSVO Sauvignon Blanc workshop. A self confessed adherent of diversity, Harrop says barrel fermented Sauvignon is a way to create that, but it needs to be treated as a halo category. Due to the very nature of the style of wine, which requires lower yields, older vines and maturation in oak, it should never be viewed as a commercial prospect.
"The process is expensive and it's a harder sell. But I see it as a halo category. That is very much how the Loire have viewed it over the years. It is five percent of their total production but it has a disproportionate impact on the commercial side of things. It is an aspiration to sommeliers and it is where our industry must go."
Learning from the greats, Harrop says New Zealanders need to concentrate on site and terroir. The wine should not be overtly fruity. There must be balanced new oak and also an integration of that oak.
"The seasoning is very important in that discussion," he said. "Whereas certain big, rich Chardonnays can handle that sort of resinous unseasoned oak quality perhaps, there is no room for that in barrel fermented Sauvignon."
Subtle, flinty aromas are important.
"Call them what you like, sulphides are very important, whether we are talking about Loire or Bordeaux or anywhere else. A bit of sulphide can enhance complexity."
The wines must also have tension and vitality on the palate.
"By tension I am talking about acidity. It's about having a fresh acid, not necessarily excessive acid, but a salty zing linking in with minerality. The flavours are alive, vital and very important."
And like all great wines, they need to be able to age.
"As they age they start to show more of their site, the terroir of the vineyard."
While Harrop says we need to look at Europe for our inspiration, he defined that further by saying the Loire and Bordeaux should be our guiding lights. The Loire in particular given at a recent tasting in the UK comparing barrel fermented wines from Loire and Bordeaux, the conclusion was the former wines were superior. They have the more marginal climate of the two regions and the vine age is much older than in Bordeaux. Think of vines that are 50 plus years old in Loire versus vines in Bordeaux that are between 20 and 30.
"This is linked to yield," Harrop explained. "The crops are pathetic in Loire, while they are a little bit more generous in Bordeaux. It is not uncommon to see in places like Sancerre, yields of under a kilogram per vine for their barrel fermented styles. This is not very commercial, but it is very important for their style."
He said producers in Loire are generally using larger barrels, from 330 to 600 litres and less new oak.
"The best producers are using 10 to 15 percent. There are producers who are fermenting 50 percent in new oak and 50 percent in barrels and then blending."
The Loire when compared with Bordeaux tends to have smaller blends, multiple cuvees, lower pH, and less intervention. A common practice he said in both regions was to inoculate in the tank and then rack to barrel after a couple of days. The ferment temperatures were generally between 18 and 20˚C, warmer than utilised in New Zealand. There is extended gross less contact and no malolactic fermentation.
So having defined how the Loire has created its reputation, what are the lessons for New Zealand?
"This is an essential category if we are to sustain the Sauvignon Blanc phenomena. We need to create this hero and barrel ferment is the approach we need to take. It accentuates our diversity as well as our vineyards.
"However this is a lost leader. You need to say I am going to put one or two percent of my production down to barrel ferment. That's going to be the vineyard (I take the fruit from), this is my house style and the crops are going to be lower."
Concentrate on older vines and allow them to reach the grand old age of 50, 60 or 70 years, he said and look for subdued fruit with enhanced minerality. He suggested large barrels are required to make the best fermented Sauvignon and low levels of new oak is best, depending on the site.
"Sympathetic winemaking is a term I use a lot. Only intervene when you need to, let the wine make itself.
"Work on the reductive spectrum which is important for minerality. Very little racking is key to making wines that age and show their site expression in time."
Think carefully about your fermentation temperatures, and maybe raise them to 18˚ – 20˚C.
Harrop said one of the problems he has seen in the past with Marlborough barrel fermented Sauvignon, is the fruit intensity is so great, it conflicts with the wood and doesn't integrate.
"So if you bring the fruit flavours out, mute them a bit through fermentation practices. Handpicking could be a key, as I believe you will get better integration of oak, regardless of how much new oak you are using."
Many Loire producers are not actually adding their sulphur onto gross lees until four to six months after fermentation, with bottling taking place 10 to 12 months after fermentation begins in barrels. That lees contact is vital he said for the end product.
Harrop could not under-estimate how important it is for New Zealand producers to take the barrel fermented category seriously, if it wants to make its mark on the world stage. There needs to be collaboration and a strong focus.
"Not for commercial, tangible, passive reasons, but more for a marketing perspective. And a very important point – to show our diversity. Not just in terms of wine style, but helping us to understand our regional potential, our site expression and our vineyard expression."
