Before the advent of refrigeration, herbs with antibacterial properties, including garlic, oregano, and thyme, were enlisted to help preserve foods that had to be stored for use during times of scarcity, such as in midwinter when fresh foods were hard to come by. These and other herbs and spices with strong lavors and aromas were also used to mask the tastes and smells of foods that were beginning to go rancid, making them more palatable.Now that we can control the temperature in our refrigerator with the turn of a dial, most of us enjoy herbs for the way they enhance the flavor and coloring of food and drink. Most recipes contain one or more ingredients purely for aesthetics — better taste, more attractive presentation. What would pickles be without dill, or pesto without basil?Purists use the word herbto refer to plants grown for their leaves and stems; spicesare those cultivated for their flowers, seeds, bark, wood, resin, and roots. You also may come across the word potherb.That’s an old term that refers to vegetables and herbs used in salads, soups, and stews. For our purposes, spicesare culinary herbs.