There are different types of sweet wines all over the world with various labels. I want to distinguish some of them to help us figure out what we’re getting when reading the label.
Defining Sweet Wines
First of all, I want to narrow the scope some or else I’ll be writing an encyclopedia here. Although there are sweet red wines like Lambrusco or Port, I wanted to limit the focus to unfortified, still, sweet white wines from grapes, which eliminates wines like Port, PX, Sherry, Sweet sparklings, Rice wine or Vins Doux Naturels wines like Banyuls from the Cotes Catalanes. Sweet reds, sparkling and fortified wines may have their own set of confusing rules and labels. Some are really their own category like PX, which can reach up to 400+ grams/liter of residual sugar (g/l rs).
Essentially, a sweet wine is defined by how much sugar is in the wine. 0-1 g/l rs is super dry, for example. By some regulations, a sweet wine means at least between around 12-45 g/l rs, but there can be a lot more. Below this amount, the wine is considered sec (dry) or off-dry. Each country and appellation may have their own terms and rules for the amount of sugar like in German speaking countries, where they use the term Trocken to mean dry wines up to 9 g/l rs of sugar. Other terms like Demi-Sec (often for sparklings) can be used to show around 32-50 g/l rs and Semi-Sweet to show more, like up to 120 g/l rs. Again, it really depends on the appellation’s rules and country’s terms.
Moreover, how sweet it feels on your palate can depend on the acidity, tannins, food pairing, etc. Therefore, it can still be confusing even if you know all the residual sugar ranges according to each appellation’s label terms.
Late Harvest
To have more residual sugar (sugar remaining after fermentation) in wine, there are a few common techniques to do so. The most common is to harvest your grapes later, or Late Harvest wine. This is Spätlese (172-209 g/l rs) or Auslese (191-260 g/l rs) in German. Late Harvest can be labeled as Vendimia Tardia in Spanish, or Vendanges Tardives in French labels. However, many international producers use the English term Late Harvest to make it clear.
A variation of this is Late Harvest Botrytis wines, or grapes that shrivel and concentrate in sugar from a noble rot/fungus called Botrytis. For French labels like from Alsace, you might see the term Sélection Grains Nobles. English labels may say Botrytis and Noble to distinguish it from regular Late Harvest sweet wines. In German, they’re labeled Beerenauslese (260+ g/l rs) although Auslese wines may have some partial botrytis. In some cases, botrytis is not possible every season or not intentional, so it’s not on the label if there’s a small amount of it.
Sometimes, you have to know the region to know it’s a Late Harvest Noble wine. The most well-known sweet wines with noble rot are sweet Tokaj wines in Hungary, and Sauternes (and other nearby Southwest France appellations like Barsac, Loupiac and Monbazillac) in France.These typically range from 120-220 g/l rs. However, for Tokaj Aszú and Eszencia wines, the higher the number of puttonyos listed on the label, the higher the amount of residual sugar.
Other Methods
Another way to sweeten wines is by drying them. This can be done many ways such as laying them on a mat in the sun or letting them hang somewhere or on the vines longer. Traditional Chilean Asoleados (which can be red or white) are made this way.
Freezing grapes is another method, or in other words Ice Wine (Eiswein in German or Vin des Glaces in French). These are late harvest grapes that are frozen (naturally on the vine or artificially in an icebox) before fermentation.
Some may have some combination of these methods like Trockenbeerenauslese wines which are from late harvest, dried grapes with botrytis.
Other French Sweet Wine Types & Terms
Although most are familiar with Sauternes because it’s connected with Bordeaux, there are other French unfortified white wines and terms you may run across. Some are labeled clearly as such while some you just have to know the appellation is known for sweet wines.
Although Alsace makes more dry whites, they can make Vendanges Tardives or Selection Grains Nobles wines like their German counterparts for Riesling, Pinot Gris or Gewurztraminer.
The Jura region makes a Vin de Paille (straw wine) that is traditionally dried on straw to develop sugar concentration. This is common in other countries like Passito wines in Italy or Strohwein in Germany.
The Loire Valley makes everything from dry to sweet wines with Chenin Blanc. Some of their dry and sweet wines have botrytis too. Major appellations like Vouvray can be sweet, semi-sweet, demi-sec, or dry. The Loire also has sweet wine specific appellations like Coteaux de l’Aubance, Anjou Coteaux de la Loire, Coteaux de Saumur and Coteaux du Layon. I recently had an off-dry/demi-sec Chenin Blanc from the small appellation of Jasnières, which makes dry and sweet white wines (I’ll include the tasting notes below).
Lastly, beyond Bordeaux and Sauternes, there are a lot of sweet wines in the South West region of France. There are sweet wine appellations within the larger appellation of Bergerac like Monbazillac, Saussignac, Haut-Montravel, Cotes de Montravel and Rosette that make Late Harvest Botrytis wines from Semillon, Sauvignon Blanc and Muscadelle like Sauternes. Jurançon, closer to the Pyrenees, is also well-known for their sweet wines made mostly from Petit and Gros Manseng. However, I reviewed dry versions a while back.
Moelleux v. Late Harvest
Another term you might see on French labels is moelleux. It simply means “soft” in French, but it denotes that this is a sweet or semi-sweet wine. In some appellations, there are rules on the amount of residual sugar to be labeled moelleux while for others it’s a loose term you can put on a label. For example, Vouvray Moelleux may contain 50-200+ g/l rs. I’ve seen Sparkling wines labeled moelleux or doux, both of which mean soft in French but sweet in wine terms. Speaking of which, don’t confuse moelleux with mousseux (or sometimes Pétillant), which means foamy or bubbly/sparkling wine. The term moelleux does not designate how the wine was made sweet, but it’s most likely a Late Harvest wine possibly with Botrytis too.
For this week’s review, I’m looking at a Cotes de Bergerac Moelleux. The Cotes de Bergerac appellation can make dry wines, but most often they’re sweet wines, so the Moelleux designation is important to distinguish it. They could also be from the above-mentioned smaller sweet wine sub-appellations of Bergerac like Monbazillac, but are given the Cotes de Bergerac Moelleux label because they’re not from one specific sub-appellation. In addition, like those other sub-appellations, Côtes de Bergerac Moelleux may have botrytis too. Therefore, this appellation could be a great bargain alternative to Sauternes. I also have a Chilean Late Harvest Botrytis Semillon wine to compare it to. Botrytis is not that common here because of the lack of humidity in Chile. 
Tasting Notes
2020 Château Marie Plaisance Côtes de Bergerac Moelleux
45% Semillon, 40% Sauvignon Gris, 15% Sauvignon Blanc. 5 months on fine lees. Around 40 g/l rs, so it’s technically more semi-sweet than sweet, and I doubt there’s much or any botrytis at this level. The nose shows spice and fresh fruit while the palate is definitely on the semi-sweet side–sort of like apple/peach iced tea. Low acid, but for a semi-sweet wine, it’s not cloying. It’s sort of a baby, mild Sauternes. I’d want a little more freshness and intensity/length, but it’s a pleasant dessert wine at a low price. 88
2022 Viu Manent Gran Reserva Noble Semillon Colchagua (500ml)
Screwtop. 100+ year old estate vines. 93% Semillon. 7% Viognier. 78 g/l rs. Some of it is aged in various aged, used French oak. 96% botrytis rate. Nose expresses some botrytis with some ginger. There’s also honey with white floral notes. The palate doesn’t have the sugar or thick texture of a Sauternes, but it gives a lighter, younger impression of Sauternes. Sauternes usually have new oak too but this doesn’t. There’s a nice streak of acidity and some spice on the finish. Balanced. Not too sweet with the acidity giving in vibrancy. 90
Bonus Tasting Note:
2020 Domaine de Bellivière Les Rosiers Jasnières
Not a huge nose, but pretty and floral. The palate is interesting with a ripe apple and peach with some residual sugar and honey but there’s a bit of spice and alcohol. Maybe there’s some botrytis. Low acid. Tasting it blind, the group was confused. The alcohol was too high with sugar and acid too low to be a sweet wine from Germany, so we guessed Pinot Blanc from Alsace not knowing if they make a demi-sec or off-dry style there. I also ventured that it was Muscat from Alsace, which is generally dry in Alsace, but it can taste sweet and have floral, low acid notes. Jasnières is a region that makes dry or sweet Chenin Blanc. Sometimes there’s botrytis too. There’s nothing on the label to lead you to believing it’s off-dry but the bottle shape is more like a German or Alsace Riesling bottle. 90+