Tartrate crystals are to be expected in certain wines in certain
vintages. The best examples I can think of are the Rieslings of Germany
from top estates in 1976. I still have many of these from Auslese to TBA
grades that have been properly stored. Nearly all of these wines have a
lot of tartrate crystals. In some of the richest BA and TBA grades, the
wines are very deep golden, and the tartrate crystals also are colored.
The 1976 vintage in many parts of Germany was very unusual with many
late harvest wines that were very ripe. Yet the wines produced by the
better estates had plenty of acid to balance the richness. The tartrate
crystals in older, properly stored Rieslings often are large enough to
produce nearly no problems in pouring the wine.

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