The back of a recently-purchased package of pine nuts has this warning: “In rare instances, people may experience a sensitivity reaction from pine nuts, termed “pine mouth,” which is characterized by a metallic taste that resolves without treatment.”

“Pine Mouth” can last for more than a week and can make all kinds of food taste terrible. Pine mouth does not happen to everyone, but can happen with pine nuts from China, which are a different species from the Italian pine nuts. The true Mediterranean pine nut (pinus pinea) is different from pinus koraiensis, which are grown in China. Of course, the pine nuts from China retail at $20 per pound, which is half the price of the Mediterranean pine nuts at nearly $40 per pound.

Although we always want the best price for ingredients, paying more for quality is more important. Finding the true Mediterranean pine nut is not easy as most retail outlets sell the least expensive nut. The Mediterranean pine nut is longer and skinnier than the shorter, plumper Chinese pine nut and the flavor of the Mediterranean nut is very buttery.

Pine nuts, which I always lightly toast, are delicious on top of salads, ground in pesto, paired with goat or blue cheese, in eggplant caponata, and many Italian cookies are full of pine nuts. The French Laundry cookbook has a memorable lemon tart with a pine nut crust. Here is my favorite eggplant appetizer, which can also be used as a sauce for pasta or tuna fish.

Caponata

1/3 cup olive oil

1 onion, chopped

1 rib of celery, diced

4 garlic cloves, minced

1 bell pepper, roasted, peeled, and diced

1 eggplant, diced

2 tomatoes, peeled, seeded, and diced (or 1 cup canned tomatoes)

¼ cup white wine

2 tablespoons sugar

4 minced anchovy fillets

1 tablespoon capers

2 tablespoons toasted pine nuts

2 tablespoons raisins or currants

salt and pepper to taste

hot red pepper flakes to taste (about a teaspoon)

fresh minced Italian parsley for garnish

In a sauté pan, heat 1 tablespoon of oil and sauté the onion and celery. Add the garlic. In a separate, nonstick skillet, heat 2 tablespoons of oil and cook the eggplant (in batches, adding more oil when necessary) until tender. Add the eggplant to the onions, with the bell pepper and tomatoes. Add the wine and sugar. Season to taste with the anchovies, capers, pine nuts, raisins, salt, pepper, red pepper, and parsley. Serve on croutons.