My wife and I had dinner yesterday evening and we could not make
either of two wines work with the dish above.

Here's the story:

We first had three small vegetarian dishes: sautéed spinach (olive
oil, browned/discarded garlic cloves and chili pepper), kidney beans
in a sofritto of onion, carrot and celery (olive oil, white wine and
fresh bay leaves) and some leftover couscous with vegetables. These
all worked perfectly well with the very inexpensive (but not bad)
Primitivo described below.

Then we wanted to move onto the Terrine (details below). We both
noticed an unpleasant aftertaste on drinking the Primitivo with the
Terrine. I thought it might be the tannins in the Primitivo, and,
using the Sauternes-goes-well-with-foie-gras analogy, I popped open
the Equinoxe white described below. (This was the first time we had
tried the wine. It was very pleasant, giving a mouthful of subtle
pear.) While not nearly as pronounced as with the red, the Equinoxe
also gave an unpleasant aftertaste.

What's going on here? Is the egg in the Terrine the difficult match?
Was the aftertaste caused by the same food component in each case? Or
did one component cause the red problem and another cause the white
problem? Were acid levels too low in these wines for this food match?
That would seem unlikely. Would an acid-sweet wine (e.g., Sauternes)
be the only possible match?

While this was not my favorite terrine, it certainly was not
"off" (well within expiry, taste was fine).

I look forward to any discussion here to really learn something about
matching this difficult food.

TB
London

*****the wines*****

The red: Primitivo di Puglia San Marzano 2007

The white: Equinoxe, Domaine de l'Arjolle, 2005 (blend of sauvignon
blanc, viognier and muscat. Full flavored with just a touch of oak.
Languedoc and Roussillon. Dry. Alcohol Level 13.5%, 6.75 GBP)

*****the terrine*****

Terrine au Bleu d'Auvergne: pork meat, poultry liver, Bleu d'Auvergne
(i.e., bleu cheese), eggs, milk, pepper, ascorbic acid, sodium nitrite
(commercial product (i.e., not freshly made) in a glass jar, room
temperature storage/consumption)