The recent appearance of the words trocken (dry) and halb-trocken (semi-dry) on some German wine labels makes it timely to take a look at what has been happening to German wine in recent years. There are those who say that German wines are not what they used to be, and that is true. Some of the changes over the past decade or so have been for the better, as a result of improvements in wine-making technology; other changes, however, are controversial.

Are German wines sweeter than they were a decade ago? These wines were seldom bonedry, but the slight touch of sweetness many of them had seemed to be a part of their fruitiness and flavor.

The 1971 German wine laws permit qualitatswein (QbA), to add sugar to the must (grape juice) before fermentation, so that when the natural grape sugar and the added sugar are converted to alcohol during fermentation, the percentage of alcohol in the wine will meet the legal requirement. Sometimes more sugar is added than is necessary to produce the required alcohol, and there remains residual (unfermented) sugar in the wine. The degree of sweetness of these wines has always varied, and they are difficult to compare with the corresponding wines made prior to the 1971 wine law.

A second category, praddikat wines, includes the attributes kabinett and spatlese (traditionally considered table wines) and, in order of ascending richness and sweetness, auslese, beerenauslese and trockenbeere-nauslese. The law forbids the addition of sugar to the juice in making these wines. Kabinett wines are made from normally ripe grapes and can be compared with their counterparts made the same way in the pre-1971 period: Those were labeled as "natural," "estate bottled," "own-growth," etc.

My own direct experience with German wines began in 1949, the year I first returned to Europe after World War II. At that time some wines from the inter-war period were still available. My recollection and tasting notes leave no doubt in my mind that most German wines are sweeter now than in the past.

There are other withesses. Going back to pre-World War I, there is an authority on all things German, the world-famous Baedeker travel guides. Baedeker's "The Rhine" of 1911, in its description of wines of the Rhine and Moselle, nowhere mentions sweetness but states that "No error has been more prevalent than that the Rhenish and Moselle wines possess an injurious acidity." In other words, the most noticeable feature of the wines was their acidity, not sweetness.

In 1940, the well-known "Grossman's Guide to Wines, Spirits and Beers" described the typical German wine as "dry and sharp," excellent with seafood and other light entrees. The late Frank Schoonmaker, probably the leading American authority on German wines, said in his "The Wines of Germany" (1957) that the auslese wines "of great years" are sweet, whereas an auslese of a good or average year may be somewhat sweet, and that spatlese and the former equivalent of kabinett are the dry wines for drinking with meals.

If the law prohibits the use of sugar in making pradikat wines, the obvious question is how the wines are made sweeter now?

The answer lies in an interpretation of the law which permits the addition of unfermented or slightly fermented grape juice to the wine. The grape juice must be from the same kind of grapes and the same quality as the grapes in the wine, so that it is not an "additive" in the usual sense. However, a small amount of grape juice, even slightly fermented, can make a noticeable difference in the sweetness of any wine.

The increased sweetness runs not only to kabinett wines, but also to spatlese and auslese . There seems to be a widespread belief among many wine drinkers, and indeed among some wine writers, that spatlese wines should be sweet, and that they are sweet because the grapes are late-picked, when they are riper. In earlier days a sweet spatlese was unusual; the additional grape sugar was converted into alcohol. The mark of a spatlese was greater body and intensity of aroma and flavor. Until very recently a spatlese could not have been called a dessert wine, but now there are some that are indeed sweet enough to accompany a simple dessert.

Why is there a sweetening of German wines? A German wine official gave two reasons. One was that the sweetness brought out the fruitiness and character of the wine; the other was that the customers like it. The latter must be true, since German wines have increased their share of the U.S. import market every year for the past several years. The first reason can furnish a topic for discussion at tastings of German wines. Many German wines I have tasted in the past few years have had sweetness well beyond what might be effective in enhancing the fruitiness and character.

The appearance of the trocken and halbtrocken wines may be the first indication of a counter-trend. The trocken wines have less than 1 percent residual sugar, the halbtrocken has less than 2 percent. I have tasted each kind and found the level of sweetness very close to that of the German wines of the first 20 years after World War II. So far I have found these wines in the Washington area only at Woodley, Morris Miller and Central.

With regular German wines selling so well, this limited availability of the dry wines may continue. Also, they are becoming more popular in Germany.

Another change, which may be controversial, is the elimination of the requirement for botrytis cinerea for beerenauslese (individually selected berries) and trockenbeerenauslese (individually selected dry berries) wines. Botrytis cinerea (the noble rot) is a fungus that appears on the grapes under certain conditions at the end of the growing season. The effect of the botrytis is to make the skin permeable enough to allow some of the water in the grape to evaporate, thus concentrating the juice in the grape. It is this concentrated juice which is used for these rich, sweet dessert wines that are scarce and very expensive.

In some years, grapes left on the vines well past normal harvest time will lose some water even without botrytis cinerea , and the juice will be concentrated enough to make a rich dessert wine, but it is questionable whether it will attain the quality of a classic beeren -or trockenbeerenaulese .

It is generally believed that spatlese and auslese wines must be made from grapes with the botrytis mold. Many accounts of tastings of these wines mention the presence of a special taste which is attributed to botrytis . Some of them may have it, but botrytis has never been required for spatlese and auslese wines.

Regardless of the changes in recent years, German wines still have a special appeal, and the top wines still display the splendid distinctive characteristics. Unless the dollar sinks even further against the mark their share of the import market will probably continue to rise.