Is safe to drink port after it has been opened for a year?

It's not recommended to drink Port wine after it has been open for a year. Here's why:

* Oxidation: Port wine is highly susceptible to oxidation, which happens when it's exposed to air. Over time, this can cause the wine to lose its vibrant color, develop a dull taste, and become more vinegary.

* Evaporation: Even if you store the bottle properly, some of the alcohol and other volatile compounds will evaporate, leading to a weaker flavor and aroma.

* Potential for spoilage: While Port is fortified with brandy, which helps preserve it, after a year, there's a higher chance of microbial spoilage.

However:

* Tawny Ports: Tawny Port, specifically, is aged in wood and is more resistant to oxidation. Some may even improve in flavor over a few years after opening. However, it's still best to consume them within 2-3 years for the optimal experience.

* Vintage Ports: Vintage Port, known for its aging potential, can be stored for several years after opening. However, it's important to note that it will develop a different character with time, becoming more mature and less fruity.

General Recommendations for Port Wine:

* Store properly: Keep the bottle upright in a cool, dark place.

* Use a vacuum stopper: This helps to minimize oxidation and evaporation.

* Drink within a few months: Most Ports are best enjoyed within 1-3 months of opening.

Ultimately, whether or not a Port is safe to drink after a year is a matter of personal preference. However, it's likely to have lost some of its original quality and taste. If you're unsure, it's always best to err on the side of caution and enjoy a freshly opened bottle.