Storing Pesto

You may wish to make larger batches, especially if you have a lot of good fresh basil at hand. After it is made, put the basil in small sterile jars, filling them 90 percent. Then add a layer of olive oil as a buffer to protect the sauce from exposure to oxygen that would spoil it. When you open the jar, dip your spoon past the oil to reach the sauce. If you do not use all of the sauce, check how much oil remains on top, and then add a drop more to totally seal the sauce. There is debate about whether or not to refrigerate the sauce, especially if the jar has been opened. Ligurians store their jars in dark places, even after they have been opened. My inclination is to store unopened jars in the pantry, but once the jar has been opened it goes into the fridge. The cold does rob the sauce of some of its flavor, but I am concerned about spoilage, especially if there is cheese present in the sauce. Unopened jars of pesto can usually last up to six months in the pantry. There are some proponents of freezing pesto (though not in Liguria), although I feel the cold kills most of the delicate properties of the sauce. Freeze at your own risk.