Hi Kristina. I’m afraid it’s not going to be worth much money. Mouton-Cadet is an affordable Bordeaux wine, one you find at your local shop or supermarket for $15-$20 or so, and it’s not meant to be aged for 30 years. The red might still be ok if it’s been stored in very cool conditions. I doubt the white will be very palatable. But I’d recommend to either keep them as a souvenir if you feel like it, or give them a try and see how they’re like!? I guess you can always put them on ebay and see what happens, there might be some collectors out there that would like such items. I don’t know. Those would be quite rare because no one keeps this type of wine for so long. But again, I doubt you’ll get any significant money for those. 🙂

-Kristina

Hi Celia. Wow!
Mouton Cadet is quite a good Bordeaux for the price, but it remains a very affordable wine that is not meant to be aged beyond just a few years.
Nearly 20 years of ageing on it seems definitely too much, especially on the white!
Then you are scaring me even further saying it was in an attic! If it went up high temperatures in there every summer for 20 years, it would have gone an even faster evolution.
Anyways, they’re worth opening up and see what they taste like. I had a great positive surprise with another affordable Bordeaux, which still was pretty decent after 30 years of ageing (in good conditions), a 1989 vintage (see article here-> http://socialvignerons.com/2016/10/02/1989-monopoles-alfred-rothschild-bordeaux-superieur-france/ ).
So you never know, Bordeaux wines can age and evolve positively remarkable well sometimes. But know that those wines that you have were not meant to aged for so long, so don’t be too disappointed if they’re not very good to taste. Expect a strong bouquet of ageing 🙂
You’ve made me curious now, so let me know how you went if you get to try them. Would love to hear how they taste.
Cheers Celia 🙂