Which type of Sherry can have an alcoholic strength of up to 22%?

Oloroso Sherry can have an alcoholic strength of up to 22%. This is primarily due to the production process, where Oloroso is fortified after the initial fermentation, ensuring that it can withstand higher alcohol levels. The fortification process is crucial because it not only impacts the wine's final strength but also contributes to its rich and complex flavor profile, characterized by oxidation.

In contrast, other types of Sherry, such as Fino and Amontillado, typically have a lower alcohol content, generally around 15-17%. Fino is kept under a layer of flor yeast, which protects it from oxidation, resulting in a lighter style. Amontillado, while it does undergo a period of aging under flor initially, is then oxidatively aged, but it usually does not reach the higher levels of Oloroso. Palo Cortado is somewhat in between Fino and Oloroso in terms of flavor and style but is also not typically as high in alcohol as Oloroso. Hence, the strength of Oloroso distinguishes it within the range of Sherry wines.