In the DO Penedès sweet wines can be made in a number of different ways depending on the grape variety used.
On the one hand, we have sweet wines made with overripened grapes, when the grapes are left on the vine until they have a high sugar content.
There is also natural sweet wine, made by partially fermenting the must and then adding alcohol before all the sugars are consumed by fermentation.
Finally we have Ice Wine, which is made by partially freezing the water in the must to achieve higher concentrations of sugars.
Other curiosities in the category: Penedès Wines