Lemon juice, rind, and peel are used in a wide variety of foods and drinks. The whole lemon is used to make marmalade, lemon curd and lemon liqueur. Lemon slices and lemon rind are used as a garnish for food and drinks. Lemon zest, the grated outer rind of the fruit, is used to add flavor to baked goods, puddings, rice, and other dishes.
Lemon juice is used to make lemonade, soft drinks, and cocktails. It is used in marinades for fish, where its acid neutralizes amines in fish by converting them into nonvolatile ammonium salts. In meat, the acid partially hydrolyzes tough collagen fibers, tenderizing the meat, but the low pH denatures the proteins, causing them to dry out when cooked. In the United Kingdom, lemon juice is frequently added to pancakes, especially on Shrove Tuesday. Lemon juice is also used as a short-term preservative on certain foods that tend to oxidize and turn brown after being sliced (enzymatic browning), such as apples, bananas, and avocados, where its acid denatures the enzymes.
In Morocco, lemons are preserved in jars or barrels of salt. The salt penetrates the peel and rind, softening them, and curing them so that they last almost indefinitely. The preserved lemon is used in a wide variety of dishes. Preserved lemons can also be found in Sicilian, Italian, Greek, and French dishes. A major industry use of the peel is manufacturing of pectin – a polysaccharide used as a gelling agent, thickening agent and stabilizer in food and other products.
Lemon oil is extracted from oil-containing cells in the skin. A machine breaks up the cells, and uses a water spray to flush off the oil. The oil/water mixture is then filtered and separated by centrifugation.
The leaves of the lemon tree are used to make a tea and for preparing cooked meats and seafoods.