Pasta sauces made with fish or shellfish are quick and delicious. Fresh seafood is often the main ingredient, but there are a few other staples that are used over and over again.
The best anchovies are the salted ones that are packed in large cans. You see them on the counters of Italian markets, where they are sold loose by the pound. They must be rinsed, skinned and filleted before use, but are plumper and more flavorsome than the fillets sold in jars and cans, so repay the effort. Anchovies are used in sauces for pasta all over Italy, but particularly in the hot South and in Sicily and Sardinia where strong and salty flavors are so popular. When chopped and heated gently with a little olive oil, they melt down to a creamy paste that is packed with flavor, so you only need to use a small amount at a time. If you can't get salted anchovies, try to locate anchovy fillets that are bottled in olive oil. These taste better than the ones canned in vegetable oil.
This is the salted and air-dried roe of mullet or tuna. The best is the mullet, bottarga di muggine. It is a great delicacy in Sardinia, Sicily and the Veneto, where they like it grated over pasta or very thinly sliced as an antipasto with lemon juice and olive oil. You can buy bottarga quite easily at Italian markets, where it is kept in vacuum packs in the refrigerator. Mullet bottarga is delicate, moist and golden, like a pale, thin version of smoked cod's roe, and bears little resemblance to tuna bottarga, which comes in a thick, dark block. For grating over pasta you need only a small amount and it can be kept in the refrigerator for a long time (check the use-by date).You can also buy grated bottarga in small jars, but this product has a dry texture, and the flavor does not compare with that of freshly grated bottarga.
In Italy, small fresh clams are frequently used in pasta sauces on the coast and in Sicily and Sardinia, but they are not always easy to get in other parts of the country or further a field. Names vary from one region and one country to another) but the name is not important; it is the size that counts. Small vongole cook quickly and have a tender texture and sweet flavor, which make them ideal for pasta sauces. Don't be tempted to buy the large ones. Some fishmongers sell frozen small clams, which are a good substitute for fresh; otherwise, you should buy the bottled shelled clams in natural juice that are sold at Italian markets Check labels carefully and don't buy the ones in vinegar or brine—these are intended for antipasto; their sharp flavor will spoil a pasta sauce. You can also buy bottled clams in their shells. These are packed in oil and, although intended primarily for antipasto, they also make an attractive garnish for a clam sauce.
Squid ink (Nero di seppia)
If you want to color homemade pasta black, you can buy handy little sachets of squid ink at fishmongers and Italian markets and delicatessens. There is usually about 4 grams of ink in each sachet, and the sachets are sold in pairs. Two sachets are enough to color a 3-egg batch of pasta all'uovo.
For pasta sauces, use only best-quality canned tuna in olive oil, not the kind packed in vegetable oil, water or brine. Some large supermarkets sell it; otherwise you will have to go to an Italian market. The flesh of good-quality tuna is moist and meaty; inferior brands are watery and tasteless. The cost of a good can of tuna is generally less than that of fresh fish, poultry or meat, so no matter how much you spend on it, pasta with a tuna sauce will still be an inexpensive meal.