The life cycle of vintage port, ageing in bottle for many years, is frequently likened to the life cycle of humans – generally an engaging childhood is followed by a possibly awkward adolescence and then years of maturity, when the wine becomes more complex, interesting and rewarding. Whilst this trajectory is typical, it is certainly not an iron-clad rule for port, any more than for people, as every vintage is different and you cannot anticipate exactly how it will develop. Bear in mind as well, proper storage makes a difference – if the wine has been stored where it has experienced rapid temperature swings, or been consistently exposed to strong light, that can adversely affect the character and life of the wine.
As a rule, young vintage port is going to be robust – very full flavoured, and dominated by red and black berry fruit flavours. Depending on the character of the particular vintage year, and the typical profile of a given brand or quinta, the flavours may be very fresh or more jammy, and there may be aromas or flavours of spices, flowers or herbs. But the overriding impression will nearly always be robustness and fruit.
Next comes that awkward adolescence. As with children, it can happen suddenly at any time, or maybe hardly at all, but for port, the period from around 8 to 10 years old up until 15 or 16 years, can be uncertain. What happens? The wine becomes, as Charles put it, neither one thing nor another. The vibrant fresh fruit character begins to subside, but no clear new flavours have arisen yet to take their place. There may be little or no aroma, or the aromas may seem to be battling during this phase.
By their late teens, the flavours and aromas of the port will have got themselves sorted out. The fruit flavours will have matured and stepped back to make room for other kinds of flavours to come to the fore. Dried fruits, particularly figs, is a typical tasting note for a mature port, cherry and black cherry flavours may come forward, marzipan, pepper and spice notes as well.
From that point until the wine is around 30 to 40 years old, the complexity builds, and the wine is likely to develop additional aromas of honey and caramel, the marzipan may become more distinct, and you may even catch a whiff of tea or cigar box. Beyond 40 or 50 years, again the comparison can be made with people – the best will age gracefully. Ports will gain complexity, elegance and delicacy. The flavours will not change or concentrate so much as lengthen – very often the finish on a really fine old port is just incredibly persistent.