Pickled Eggs

Common pickled eggs are made by first boiling the eggs and then immersing them in a solution of vinegar, salt, spices, and often a coloring like beet juice, for 1 to 3 weeks. Over that time the vinegar’s acetic acid dissolves much of the shell’s calcium carbonate, penetrates the eggs, and lowers their pH sufficiently to prevent the growth of spoilage microbes. (The vinegar in Easter-egg dyes etches the shell surface and helps the dye penetrate.) Pickled eggs will keep for a year or more without refrigeration.