Lemons are a healthy citrus fruit full of vitamins, minerals, citric acid and antioxidants. Because of their sour taste and low sugar content, lemons are usually added to drinks or foods, especially baked desserts. Lemon juice is also commonly used in cooking to prevent discoloring of sliced fruits such as apples and bananas.
True lemons are pale yellow in color and grow to about 2.5 to 4.5 inches in length. The tree can be from 10 ft. to 20 ft. high with sharp thorns on the branches, not commonly found on commercial hybrids. Lemon trees require warm climates to grow, as temperatures 29 degrees Fahrenheit or below can kill all flowers and fruit, and possibly damage the tree. True lemons are believed to originate in northwestern India, but are grown around the world, wherever climate and soil conditions are adequate.
There are several varieties of lemons cultivated. Many are crossbreeds and can vary in size and color. Armstrong is naturally seedless and was discovered in California. Berna is a Spanish lemon that ripens in winter and has very few seeds. There are several types from Italy and include the Genoa, Femminello Ovale, Bearss and Santa Teresa. One of the more popular lemons is the Meyer, which is believed to be a cross between a lemon and mandarin orange.
Citric Acid in Lemons
Citric acid is a compound considered weak and is found in fruits, such as lemons, oranges and grapefruits. The citric acid found in lemons and limes is much more plentiful than that of grapefruits and oranges. According to the National Institutes of Health, fresh-squeezed juice from lemons contains 1.44 g of citric acid per ounce, and lemon juice concentrate contains 1.10 g per ounce.
Nutritional Data on Lemon Juice
Lemons are known for their high citric acid content, but they also provide a small amount of several vitamins and minerals. A 1-cup serving of raw lemon juice provides 61 calories and zero fat. It will also offer up 0.9 g of protein, 48.8 IU of vitamin A, 112 mg of vitamin C, 0.4 mg of vitamin E, 0.1 mg of thiamine, 0.2 mg of niacin, 0.1 mg of vitamin B-6, 31.7 mcg of folate, 0.3 mg of pantothenic acid and 12.4 mg of choline. This same juice will also give you 17.1 mg of calcium, 0.1 mg of iron, 14.6 mg of magnesium, 14.6 mg of phosphorus, 303 mg of potassium, 2.4 mg of sodium, 0.1 mg of zinc, 0.1 mg of copper and 0.2 mcg of selenium.
Lemons are high in vitamin C, which provides antioxidants. Antioxidants are valuable to the body as they will attack and kill free radicals, which are known to cause cancer and damage blood vessels. Lemons also contain limonoids, which are able to prevent certain cancers, such as skin, mouth, breast and colon.
- Purdue University: Lemon
- National Center for Biotechnology Information: Citric Acid
- National Institutes of Health: Quantitative Assessment of Citric Acid in Lemon Juice, Lime Juice, and Commercially-Available Fruit Juice Products
- Nutrition Data: Lemon Juice, Raw
- World's Healthiest Foods: Lemons/Limes