Why are some desert wines (like gewurztraminer) thicker or more syrupyer then normal wines?
WOW, 500 posts!
Dessert wines have a higher residual sugar content, which makes them sweeter and more “syrupy.” The grapes are usually left on the vine longer, until they get the “noble rot” which concentrates the sugars. When fermented, only part of the sugar converts to alcohol, leaving more behind to sweeten the final product.
Maybe the ‘desert’ wines are dehydrated.
:dnr:
To expand on silensu’s answer, as you leave grapes unharvested, they get sweeter and sweeter, because on every sunny day they’re photosynthesizing sunlight into sugar stored in the fruit. You make a dessert wine by harvesting as late as possible and then also finding a way to remove excess water from the grape – so you’ve got more sugar, highly concentrated. One of the ways to do this is to leave it out long enough that higher temperatures or the “noble rot” (a fungus, IIRC, but I may be wrong about that) arrive and start to dry out the grape, making it raisin-like. Dessert wines can also be made by letting the grapes freeze on the vine, thus Eiswien (literally, Ice Wine).
This is why dessert wine is expensive – because the sugar in them is concentrated, it takes more grapes to make a quantity of dessert wine than of table wine, so the vintner’s materials cost is significantly higher. Plus, since the grapes are left unharvested longer, there may be additional labor costs in there too. (Again, I ain’t no oenologist.)
Gewurtztraminer, BTW is not exclusively a dessert wine and shows up in table wines from Germany and Alsace, some of which are sweet, and some of which are dry. But like most grapes, it can be made into a dessert wine by one of the methods of concentrating sugars discussed above. Also, you’ll frequently run across a Gewurtz labeled “Spatlase,” which means “late harvest.” These grapes were left on the vine, not long enough to become the fodder for a dessert wine, but longer than standard, thereby producing more sugar. These wines are typically somewhat sweet (but by no means syruply so). Because sugar in the grape turns into alcohol during fermenting, you can make any given wine either sweeter or boozier, so you can make a dry Spatlase by fermenting it to the hilt. Just make sure you give someone your car keys before you drink it. 
–Cliffy
It was once my privilege to drink a glass of Chateau D’Yquem (Sauternes) - easily the most remarkable liquid I’ve ever tasted. It certainly wasn’t syrupy, though it was quite smooth and I guess you’d call it sweet. In truth, it wasn’t like any taste I’ve encountered before or since, and I’m not sure there are adjectives to accurately describe it. Sure was good, though.
You are quite correct in stating that the longer the grape is left out it will reach higher sugar levels but there must also be a balancing between sugar (measured as % brix) and acidity. If you are making dry wines you normally convert all sugar to alcohol. Dessert wines are typically made in one of two ways - the first method involves stopping the fermentation process before all of the sugar is converted to alcohol and this usually accomplished by adding sulphites and the second involves adding brandy or other distilled spirits to a wine to raise the alcohol level above 18% or so at which the yeast dies and can no longer sustain the fermentation. The latter category of sweet wines are called fortified and this is how port, sherry, and madeira are made. In some cases the grapes are picked in a normal fashion and then the grapes are set out in the sun to dry on mats or other contrivances. For example, this is the method used to make the famous Italian wines Amarone de Valpolicella (where the sugar is completely fermented and the resulting taste is bitter) or Recioto de Valpolicella (where residual sugar is left and you have a sweet/bitter taste)
The other huge risk you are taking is losing the grapes for other reasons such as rain which will tend to swell the grapes up with water and other fungus attacks that are not good for the grapes. The longer they are on the vine the higher the risk of spoilage (water, other fungus, etc.). Regarding the labor issue, one factor is that most grapes exposed to “noble rot” have to be hand picked since not all grapes in the bunch will have the fungus to the same extent. Also, If you’ve ever gone shopping for dessert wines you’ve probably noticed that it is most commonly sold in 375 ml bottle and even so the prices for Sauternes
Alsatian gewurz and reislings, for that matter, are usually fermented bone dry because the cold climate of the region won’t allow the grape sugars to get very high.
In regards to Spatlese, which has to do with German wines, I am going to repeat some information that I posted on a previous thread concerning the "rankings’ or “categories” of German wines.
There are two general categories of rating German wines:
- QbA (Qualitätswein bestimmter Anbaugebiete), and
- QmP (Qualitätswein mit Pradikät).
QbA wines are generally not found here in America as they represent the low end of the market and most are not exported out of Germany. Some are exported amid great confusion though QbA should be less expensive than any QmP wine.
QmP wines are further broken down in the following order of increasing levels of sugar in the grapes at the time they are harvested ). While these apply to all grape varietals in Germany they are most often seen in German rieslings since these are the most commonly exported wines.
Qualistat
Kabinett
Spatlese
Auslese
Berenauslese
Trockenberenauslese (TBA)
Eiswein
Wines that are at the Qualistat level are usually simply designated as QmP on their lables without any further identification. All of the others will be labeled as QmP along with the added designation if applicable.
While these ratings or classifications are based on the level of sugar in the grapes at the time they are harvested (except for eiswein, which require that the grapes be harvested while they are frozen on the vines) this also generally speaking equates to increasing levels of sweetness since most German wine makers strive for relatively low alcohol levels. It is not uncommon to find these wines in the 8.0-8.5 % alcohol ranges (compared to 10% or more elsewhere).
There are as many different dessert wines as there dry wines with many of them commanding huge prices of thousands of dollars per bottle such as the famous Chateau de Yquem in Sauternes.
What year did you have the pleasure of drinking?
Try a good Hungarian Tokaji Aszu (preferably 6 puttonyos–the Tokaji Aszus are rated on a scale of 3-6 denoting how many puttony [a type of cask] of the late-harvest noble rot grapes are used in the final product. The higher the number, the sweeter and, generally, desireable the wine.) Personally, a think a good Tokaji Aszu is better than a great Sauternes.
Actually the ratings go beyond the 6 puttonyos with two additional non-numbered levels: *Tokaji Aszuesszencia * is the equivalent of at least 7 puttonyos whereas Esszensia is the pure nectar obtained from the grapes and can contain upwards of 850 grams of sugar per liter. It is so concentrated in sugar that it requires a special yeast for fermentation and even then it can take decades to ferment up to a 5-6% alcohol content. There was an article that I saw recently describing the opening and drinking of a bottle of this legendary wine that was dated 1611 and was still drinkable.
I have some 6 puttonyosTokaji Aszu, but alas the best I’ve done is a second growth Sauternes so I can’t compare. Anyone willing to send forth a bottle of Chateau D’Yquem so that I can make a comparison and I promise I will report back the results. 
I can’t recall, but I might be able to find out. I think my brother-in-law still has the empty bottle.
The story is that in 1983 a G-7 summit was held in Willaimsburg VA; Regan, Mitterand, Gorbachov & Thatcher (and possibly some others) attended. A big dinner was held at the Williamsburg Inn, where my BIL worked as a wine steward. Mitterand brought a case of the Chateau D’Yquem, not all of which was consumed; BIL was given a 3/4 full bottle to take home, from which I got a glass. I seem to recall a date from the 1960s.
Yes, I neglected to mention those becase I can’t afford 'em. 
The Eszencia, like you said, is extremely sweet and has very little alcohol–like only 2.5%. It’s from the juice of the grapes pressed by their own weight. Aszu Eszencia is more like 12% alcohol, and is almost purely just the grapes of noble rot (botrytis). Aszu is blended with Furmint, Harslevelu, and Muskotalyos (Muscat) grapes, I believe (I’m going on memory here.)
There’s also the Tokaji Szamorodni (from the Polish word meaning, basically, “as it is grown”) which is made from grapes as they are grown, i.e. not selectively hand-picked for their noble rot, and thus contain a lower %age of botrytised grapes. These range from dry to sweet, and do have the signature Tokaji aszu taste, but much less sweet and, in my opinion, much less refined.
I hope I’m not intruding but I checked your profile and I’m curious as to whether or not you can offer a picture of some botrytised grapes?
I have only seen the Esszencia once (at Sam’s) but alas I also couldn’t afford it along with the bottles of 1961 and 1981 Chateau Petrus and some others of astronomical prices.
You know, I wish I had some pictures but, believe it or not, in the five years I spent in Hungary, I never once went up to the Tokaji region for the harvest?
I am going again in late November for a visit, but I’m afraid I’m just going to miss the harvest. 
IIRC, in Hungary the Eszencias start at around $80-$100. If you live in the Chicago area (which I assume is what Sam’s refers to, although your Location shows Richland), I could have a look for you while I’m out there.
My (single, alas) bottle of Esszencia sez that it’s a 7% alcohol–still quite low for wine, but certainly less astonishing than 2.5%. My bottle of Aszu Esszencia sez that it’s 9%. I don’t have a bottle of 6-putt at the moment, but my 5-putt bottle is listed as 12%.
Is There another Sam’s (though they have one in Downers Grove and rumours about opening in NY)? I lived in Chicago for about five years before venturing out west.
Unfortunately I don’t think I can afford any of the Eszencias but have one (or more) for me and thanks.
7%? That’s pretty high for an Eszencia. Most range in the 2-3% level. Some even lower.
Aszu Eszencia is all over the map in terms of alcohol content, but ranges, as you noted from 7%-12%. I suppose a better average would be 10%.
I never said different; the OP wasn’t asking about dry wines.
In my lay experience, “dessert wines” usually refer to sweet wines made by starting with sweet grapes concentrated to high level, contrasted with the fortified wines made by adding brandy as you note. Perhaps that’s wrong.
I certainly agree, but I’ve seen some pretty high-proof Spatlase wines from time to time. I remember taking a 12.5% bottle to a party once and being pleasantly surprised that it still had a touch of sweetness. It must have started with a high brix; maybe it was grown to the south.
–Cliffy
