What statistical test can I use for data obtained from a taste test?

I had to do a taste test between Pepsi and Coca-Cola to see if people could tell the difference between the two beverages based on taste alone. I had the subjects taste a beverage and mark down what they thought it was. There were 2 rounds. Now, I have to do a statistical test to see if the results were accidental or not. I have no idea what to do. What test do I use? If anyone can help, I would really appreciate it.