Single Pot Still Irish Whiskey Redbreast 21 Year Old is the oldest expression from Redbreast so far, this is a combination of malted and unmalted barley matured in a mixture of bourbon barrels and first-fill oloroso casks, resulting in a rich and complex whiskey. Please note: As Redbreast 21YO packaging has changed, if you order online you may receive a bottle of the old label. See image 2.