Numbers vs. Taste:
Getting the Best Quality Grapes

Eric von Krosigk


The following notes are from a presentation by Eric von Krosigk to a meeting of the Nanaimo Winemakers on March 5, 2004. Because Eric spoke without notes and responded to questions at various points, these notes sometimes rearrange material under related topics.

Eric von Krosigk is well known as one of BC's premier winemakers. He is currently winemaker at Victoria Estates Winery, where he helped design the new state-of-the-art facility. He is also winemaker for four other (soon to be six other) BC wineries. He sources grapes from 38 growers, including the Black Sage Growers in the Okanagan. Eric has been making wine for more than twenty years. He has worked in Germany as well as BC.

Picking grapes at the right point

Your wine is only as good as your grapes. 75% of your wine quality depends on your grapes, but people never blame the grape grower, only the winemaker. Getting good grapes makes you or breaks you. When to pick is a critical decision.

Know the style of wine you want to make

Knowing what kind of wine you want to make is the number one thing. Every grape has a flavor spectrum. For example:

What you should expect in your grapes

Grapes should be clean. No mildew. You should put your nose in the bin-the smell should be clean and fresh.

If there are bird-pecked grapes, throw them out. They are a VA source. There are lots of spores about and grapes quickly get infected. If there are grapes with white mold, don't use them. Rain can cause grey mold which is botrytis [i.e., bunch rot or grey rot, not the good kind of botrytis infection] and blue mold which is penicillin. You do not want mold or wild yeast problems that come with damaged grapes.

How I determine picking time

You don't need ideal specs to make good wines. The bottom line is that numbers lie. If you pick on the same parameters year after year, you will get completely different grapes because of various other factors like heat and water.

To make sure I get the best grapes, I walk the vineyards. I start in August and by early September I walk them once a week. As harvest gets closer I visit three times a week.

I watch the irrigation program. Water management is the single largest problem in the Okanagan-too much water produces grapes with little flavor. I check soil moisture and canopy/leaf management. Even the day before picking I go through the vineyard to see they don't add water. You can tell if there has been too much water early in the season by checking the internodes on the vines- too much space, i.e., greater than 3 to 4 inches, [between the branches that carry clusters and leaves] means too much water. If one has to prune the vines heavily you are growing wood, not grapes. Again too much water. Later, berry size is critical-especially in reds. Grapes should be the size of a fat blueberry. Larger, especially with Syrah, means too much water.

I bite and taste the grapes, looking for intensity. The intensity you are looking for is like the intensity of a perfectly ripe peach picked directly from the tree.

None of this looking and tasting for optimum ripeness and mature flavors takes a mass spectrometer.

pH and TA are not usually concerns. For Reds I like the extra weight that comes with a higher pH. 3.6 is ideal for reds, and 3.7 or 3.8 are okay. The higher pH gives more body and mouth feel. With Pinot Noir and Gamay I have actually used calcium carbonate to raise the pH a bit to get more body and take the edge off the acid. Some people have expressed concern about whether a high pH limits longevity. I think probably not. Wines from the south of France do fine.

I never worry about a high pH in reds. However, at 4.0 pH is a problem. You risk soapy-ness. You need to reconstitute the acids. I like to add back both tartaric and malic (although I know some people only add tartaric). [GGG Note: The readily available malic acid is a mixture of L-malic and D-malic. The L-malic is susceptible to decarboxylation-conversion to lactic-by ML bacteria; the D- malic is not.]

You can have too much malic in whites, especially in unripe Chardonnay. If you do malolactic fermentation, you can end up with so much lactic acid you get a sauerkraut taste.

Winemaking with Black Sage grapes

The most important general point is to make your adjustments for sugar and acid in the juice or must. Anything you do to a wine [i.e, after fermentation] hurts it. The higher sugar and alcohol levels of recent pickings means there is less acid held in the grapes.

Reds

You will need to add tannins and then the wine will age well-VR-Supra at the start, and perhaps others later. Red grapes grown on clay soils have lots of tannin. But the Black Sage area is sand, and the tannins are very soft. You need to add some. This will also aid in getting color stability.

How much acid and tannin you add to reds will depend on the style of wine you want to make. If you are freezing red must the pH will go up by 0.2 units.

Big reds? Everyone wants to produce them. The Okanagan can produce medium-bodied reds. There are some grapes that can make big wines in the Okanagan, but they are few and far between.

Aging reds in small barrels (56 liter size) for 3 to 6 months will equate to aging for two years in a large commercial barrel.

Whites

With whites there are problems with grapes that have become over-ripe in order to get the mature flavors. If a white juice has high sugar and low TA adding citric acid or tannins to the juice can help. You can't fix over-ripe after the fact. If sugar is high, leave it and ferment cool. Sometime you get "pinking" in over-ripe whites. You can fine with PVPP [polyvinylpolypyrolidone, also called polyclar].

For fresh-tasting whites, you need to pick earlier. Then ferment cold at 10-12ºC. Stopping the ferment is better than back-sweetening. Just put the fermenting wine in the freezer overnight [i.e., get it very cold; don't actually freeze it]. Then hit it with S02 and fine with bentonite to get rid of the protein and starve the yeast. Rack right away and filter early.

Minimizing H2S problems

H2S comes from nutrient deficiencies in grapes and from spray residues. I have found that Opti- Red works great in helping to reduce H2S and to prevent stuck fermentations. I don't try to keep the fermentation temperature low. I like to get it up to 25-30º by the 4th day. This gives better color and body. Punch down the cap 3 to 4 times per day.

Oxygenated rack and return can be used. It helps to fix color. Micro-oxygenation is the rage now, but it not simply a matter of getting a pump and blows bubbles into the wine like you would a fish tank. It must be done above a temperature of 14-15º. Racking often gets rid of the H2S. You can rack if you have reasonable tannin levels. In Bordeaux they give their fermentations little air, they rack only three times, and they fine with egg whites, and they find that this is enough.

Adding copper sulfate is a possibility, but it speeds up the aging of the wine and the wine will not keep as long. The presence of copper speeds up a number of chemical processes in a wine.

There are two schools of though about yeasts and H2S—that yeasts make a difference or they don't. I think they do make a difference. Some yeasts do a better job in not producing H2S—for example D-47 for whites and D-254 for reds. VL3 also does a good job on Gewürztraminer, and there is always the standard 1118.

I have come to favor yeast cocktails. I may add a mixture of five different yeasts to the must. You have to make sure that one of the yeasts is not a killer, but otherwise the cocktails seem to work fine. They produce more flavor complexity. I also like to include one yeast that is a glycerin builder.

Tasting a 2002 Merlot

Eric had brought a 2002 Merlot for people to taste. It was made from Black Sage grapes that were picked very ripe with somewhat jammy tastes. It was a "market-driven" wine. It had to be done for $15.95 price point. This means one can't buy the best grapes or use barrels. This wine had "seen" oak—a phrase that was later explained as "micro-barrels" [i.e., oak chips]. The wine had 13.5% alcohol, a TA of 5.5, a pH of 3.8, and 2 gm of residual sugar.

There had been a 4-day cold soak (less than 10º C) protected by 30 ppm SO2. Then a 6-day ferment, pressed off at 6 Brix. The crush included 60% whole berries, so there was an element of carbonic macerations [which enhances fruit flavors in young wines]. The process was all about fruit. The tannins are out; it is fruit forward.

The wine is meant to be drunk early. Winemakers figure a wine has a shelf-life of 48 hours—in other words it is going to be drunk within 48 hours after it leaves the store. The point is to get a wine that is drinkable now.

Getting better grapes from the Okanagan

You have a broker who is trying to do a good job. You need to go to him with your concerns: What are you going to do for us? Get us a new supplier? Cut the price?

You are serious group and you are paying good money. Tell your broker you are not happy with particular grapes. He has access to a lot of different vineyards.

Ask which blocks your grapes are coming from. Engage a consultant. Put your cards on the table. Say this is what you want and this is the way it is going to be.

You need to have somebody up there, somebody who will walk the vineyard. Take a trailer, camp out. Showing the flag is 50% of winning. Even if all your presence does is ensure that they are not over-watering, you have gained. Half of winning is just showing up. Ask which blocks your grapes are coming from and say you want to check. If you don't like what you see, you can make your case.

One of your major problems is logistics. Grapes can change quite a bit during delivery. Think of what a ripe peach would be like after it is trucked in boxes for any distance—it will be bruised, starting to deteriorate. You need to pick ripe grapes. But truck them at 1ºC—this helps firm them up. And process them as soon as possible. From picking to processing, 6-7 hours is ideal, but even in wineries 48 hours is normal.

Other issues

Quality improvement in the Okanagan

Everything is getting better in terms of quality.

Our grapes are better—a lot better. Part of the explanation is the weather. It has been better recently. Whites are now getting very high alcohol levels (even 13.5% to 14%) as winemakers wait for flavors to develop. Alcohol also induces flavor and aroma. If there is enough sugar-free extract wines can withstand high alcohols.

Competition is big part of the explanation. Free trade in wine came into effect in just one year. We had to compete. The LDB also promotes competition. You can get wines from all over the world here. We can't compete with many of these on price, so it has to be quality.

There has been purchases of new equipment, new barrels, new everything. Barrels used to be used forever. And equipment was old and run down. All that has changed. And winemakers have changed too.

Grape varieties and vine age in the Okanagan

Yes, Syrah will probably do well in the Okanagan. And yes, Foch can produce an excellent wine. There can be a foxy character to Foch, but you can get rid of it by adding charcoal to the must.

We haven't a recent variety shakeout in the Okanagan [i.e., we grow lots of varieties in an attempt to find which ones work best and we haven't started to eliminate the poorer ones yet], but the Okanagan will probably produce a lot of varieties for next few decades at least. There are lots of different ethnic backgrounds at work in the Okanagan. They have brought grapes and aspirations from many places. These are being tried out. We just don't know yet which sites are best for which grapes.

I am not sure that older vines are necessarily better. The conventional view is that 40-year old vines produce less but with a more concentrated flavor. But if you talk to the people at the great French châteaux, they will not agree. They say it is growing practices and getting the right balance of fruit and vine. In the Rheingau they also don't believe older vines are necessarily better. They have the view that vines have only so much to give. You can take it in 15 years [with heavier crops] or 40 years [with lighter crops]. But 80-90 year old vines (if you can find them or afford them) almost always have intense flavors because the yield is so low.

Vancouver Island grapes

Yes, there certainly are differences between Okanagan and Vancouver Island grapes. Maréchal Foch is about the same—it even ripens about the same time. Agria, Ortega, Siegerrebe, and Gewürztraminer do well on the Island. Gewürztraminer does better on north slopes in warmer climates, so the flavor doesn't get baked out. The Island has good locations for it.

The Island's problems are hang time, rain, and the fungus that comes with the high humidity. There is more botrytis, mold, and mildew. This means you need a more rigorous spray regime and you need to spray later on the Island. If Botrytis hits below 18 Brix you will get a concentration of the bad flavors.

The best advice on spraying is in a manual available through www.WineTitles.com.au [Editor's note: Found the site; could not immediately identify the book.]

Island grapes are always high acid. You need to deacidify early at the must or juice stage. I use calcium carbonate or sometimes acidex on whites. Always leave an extra gram of acid above your finished wine target level when you deacidify, because you will lose a gram in the ferment.

Big reds? The flavors are too green for big reds on the Island.

Dornfelder for the Island? I haven't tasted it yet. It should be good. Regent is also a good possibility.

When to drink wines

Yes, I agree, most wines today are drunk too young. It is the Australian and Californian influence where they go for the grape candy effect, with big varietal fruit and 7 grams of residual sugar.

Even with whites, Chardonnay should sit for 2 or more years, Riesling for 4 years, Gewürztraminer for a year.

With a cellar temperature at 8ºC, a good cork, no light, and no vibrations, any wine will last a long time.

Corks

I like real cork. Reds must get some oxygen or else you can get a redox reaction with wet-dog and mercaptans. Artificial and plastic corks don't allow wines to breath. You might as well have a screw cap. And with artificial corks, who knows? When I die, I want to know why I died.


Notes prepared by Rod Church with help from Doug Morrison and George Gibson.

March 2004