Nutritional value and health benefits of apple

Introduction

The apple is the pomaceous fruit of the apple tree, species malus domestica in the rose family Rosaceae.  It is one of the most widely cultivated tree fruits. The tree is small and deciduous, reaching tall, with a broad, often densely twiggy crown. The leaves are alternatively arranged simple ovals 5cm to 12cm long and broad on a petiole with an acute tip, serrated margin and a slightly downy underside. Blossoms are produced in spring simultaneously with the budding of the leaves. The flowers are white with a pink tinge that gradually fades five petals and in diameter. The fruit mature in autumn and is typically diameter.  The center of the fruit contains five carpals arranged in a five- point star, each carpel containing one to three seeds.

The tree originated from central Asia, where its wild ancestor is still found today. There are more than 7,500 known cultivars of apples resulting in a range of desired characteristics.  Cultivars vary in their yield and the ultimate size of the tree, even when grown on the same rootstock.

At least 55 million tons of apples were grown worldwide in 2005, with a value of about $ 10 billion. China produced about 35% of this total. The United States is the second leading producer, with more than 7.5% of the world production. Turkey, France, Italy and Iran are also among the leading apple exporters.

Historical background of apple

The fruit is one of the oldest varieties in existence, a research study state that humans have enjoyed apples ever since at least 6500 B.C. The fruits were among the favourite lists of Ancient Greeks and Romans. In Norse tradition a more positive guise was giver to the fruit i.e. a magic apple was said to keep people youthful eternally.

Most  historian  believe the apple originated in the Dzungaria Alps, a mountain range separating Kazakhstan, Kyrgyzstan and China, were wild apple trees still produce teensy apples the size and shape of the seedy and sour ancestors of the world’s favourite tree fruits. Others insist the wild apple arose in the Caucasus Mountains between the Black and Caspian seas. Whichever is true as early humans migrated to other lands, they carried apples with them until apples became established throughout all of Asia, the Mediterranean region and the Middle East.

A tablet found in Mesopotamia dating from 1500 B.C. records the sale of an apple orchard by an Assyrian named Tupkitillla. The price, the princely sum of three prized breeder sheep. In the 13^th century B.C. Egyptian pharaoh Ramses the Great ordered domestic apples grown in the Nile Delta.

The ancient Greeks were fond of apples as evidenced by Homer’s writings. In 323 B.C. the Greeks botanists, Theophrastus, sang the praises of six different varieties of apples and described the art of budding and grafting apples. Rome followed Greece’s lead and soon embraced apples. The lyric poet Horace (65 – 8 BC) waxed enthusiastic of apples while Cicero (106 – 43 B.C) encouraged the cultivation of new apple cultivars. Pliny the Elder (23 -79 A.D) described 37 varieties of cultivated apples grown throughout the Roman Empire.

As Caesar’s legions conquered continental Europe and the British Isles, they carried apple seeds and planted orchards to supplement native crab apples they found growing wild along the way. By the first century A.D., orchard grown apples were established as far north as the Rhine valley of Germany. Later orchard grown apples were grown in monastery and convert orchards through Great Britain and Europe. Naturally apples crossed the Atlantic when the new American colonies were founded in the early year of the 17^th century.

Types of apples

There are about 7,500 varieties of apples in the world; according to cook’s wisdom we have 18 varieties of apple that are commonly known. They include:

1. Red delicious: A popular eating apple that looks just how we all imagine an apple should look, unfortunately due to overlong storage or super markets selling the Red Delicious out of its natural season. Many Specimens have a mushy and tasteless flesh.
2. Golden delicious: Sweet juicy and mild, this is probably the most widely available apple.
3. Granny smith: Originally from Australia, this bright green apple boasts white, firm juicy flesh that is sweet and tart at the same time.
4. Gala: Native to New Zealand, the Gala is pleasantly sweet crisp with golden skin and a rosy overtone.
5. Mcintosh: This is a fall favorite, with its red skin and crisp, white, juicy flesh.
6. Cortland: This red skinned apple with snow white flesh has a pleasing tartness and a firm texture.
7. Empire: Red or green-skinned, this juicy apple with a tart-sweet flavor and creamy flesh is a cross between Red delicious and Mcintosh.
8. Fuji: The Fuji with its yellowish-green skin and juicy white flesh has a sweet and slightly spicy apple flavor. This apple, developed in Japan in the 1960s, is particularly prized for eating out of hand.
9. Honey crisp: This large apple with its streaks of red and green has a juicy, crisp flesh and mellow flavor.
10. Ida red: A good–looking red apple with a hint of green, this milky tart fruit is prized for baking and cooking.
11. Jonagold: His cross between the Jonathan and the Golden delicious has red streaked yellow skin and firm, sweet, juicy, white flesh.
12. Jonathan: Most Jonathans are used for baking or cooking, although the golden apples with red stripes and juicy yellow flesh are good for eaten raw too.
13. Northern spy: Red-blushed with green water tones, this juicy sweet apple makes wonderful pies and sauces and holds its shape when baked. It’s also good for eating raw.
14. Pippin: The term pippin turns up in a number of apple names, but the best known of them is the Newton pippin usually simply called pippin. This all purpose apple with its pale green or yellow skin and creamy flesh, has a bright, tart, full flower and stem texture that makes it a favourite in pies.
15. Rhode Island greening: A lovely green apple with crisp, tart, juicy, green-toned flesh that is excellent for pies and apple sauce.
16. Rome beauty: This large, red apple has sweet-tart, firm flesh and holds its shape when baked.
17. Wine sap: Sometimes called a stay man wine sap, this dark red apple has firm, crisp flesh and a sweet, winy flavour, characteristics that gives it a loyal following among apple aficionados.
18. York: Moldy tart, this deep red apple with green stripes is a very good baking apple and makes fine apple sauce.

Chemical constituents of apples

The main constituents that contribute to the apples vast usefulness and great taste are hard to narrow down over twenty have been documented in the unpeeled fruit alone to contribute a vast amount of biological activities. Those with known biological activities located in either the fruits or peel or both are: Alpha – linolenic – Acid, Asparagine, O – categin, Isoqurctrin, Hyperside, ferulic –Acid, farnesene,  Neoxathin, phosphtidyl – choline, Reynoutrin, sinapic – Acid, caffeic- Acid, chlorogenic – acid, P-Hydroxy- Benzoic-Acid, p-coumaric Acid, Auicularin, Lutein, Quercitin, Rutin, Unsolic-Acid,  Protocatechuic-Acid and silver from Dr. James Duke’s phytochemical and Ethnobotanical Database website, we find that in addition to these phytochemicals the whole fruits contain many more for which the biological activity is not yet known. Many of the benefits of the apple came from enzymes and flavinoids.

The “nutrition Almanac” by Lavon J. Dunne gives us further nutritional information on the apple. In one medium apple weighing about five ounce we find the following constituents of vitamins and minerals, vitamin A, B, B₂, and B₆, Niacin, pantothenic acid, folic acid, vitamin C and vitamin E, calcium, copper, iron, magnesium, manganese, phosphorous, potassium, selenium, sodium, and zinc. The fats in the apple contain no cholesterol. Instead they are a blend of liquids, saturated, unsaturated and monounsaturated fats. In addition to fats, the apple contains the other macronutrients of proteins and carbohydrate.

Other phytochemicals include; tryptophan, threorine, isolewcine, lowcine, lycine, methionine, cystine, phenylalanine tryrosine, valine, Argenine, histidine, Alanine, Asportic acid, Glutamic acid, glycine, preline and serine. Trace amounts of boron and cobalt are found in apples. There are four to five grams of soluble and insoluble fibre per apple. This fibre is from cellulose, protein and lignin. The sugars of fructose and sucrose make up about 9% to 12% of the fruit and give it its sweet taste, while the tartness comes from the malic, tartaric and citric acids the tamnins, making up 0.2%, give it an astringent cooling and thirst quenching effect. Finally, annygdalina, naturally occurring cyanide is found in the seeds.

Nutritive value of apple

Nutritive value of apple per 100g

Health benefits of apple

According to Best Health Magazine (2016), the following are the health benefits of apple.

1. Get whiter, healthier teeth: An apple won’t replace your toothbrush, but biting and chewing an apple stimulates the production of saliva in your mouth, reducing tooth decay by lowering the levels of bacteria.
2. Reduce cholesterol: The soluble fibre found in apples binds with fats in the intestine. This translates into lower cholesterol level and a healthier you.
3. Healthier heart: An extensive body of research has linked high soluble fibre intake with a slower build up of cholesterol-rich plague in your arteries. The phenolic compound found in apples skins also prevents the cholesterol that gets into your system from solidifying on your artery walls. When plague builds inside your arteries, it reduces blood flow to your heart, leading to coronary artery disease.
4. Prevent gallstones: Gallstones form when there is too much cholesterol in your bile for it to remain as a liquid, so it solidifies. They are particularly prevalent in the obese. To prevent gallstones, doctors recommend a diet high in fibre to help you control your weight and cholesterol levels.
5. Beat diarrhoea and constipation: Whether you can’t go to the bathroom or you just can’t stop, fibre found in apples can help. Fibre can either pull water out of your colon to keep things moving along when you’re backed up or absorb excess water from your stool to slow your bowel down.
6. Neutralize irritable bowel syndrome: Irritable bowel syndrome is characterized by constipation, diarrhoea and abdominal pain and bloating. To control these symptoms doctors recommend staying away from dairy and fatty foods while including a high intake of fibre in your diet.
7. Avert haemorrhoids: Haemorrhoids are a swollen vein in the anal, canal and while not life threatening, these veins can be very painful. They are caused by too much pressure in the pelvic and rectal areas. Part and parcel with controlling constipation. Fibre can prevent you from straining too much when going to the bathroom and thereby help alleviate haemorrhoids.
8. Control your weight: Many health problems are associated with being overweight, among them heart disease, stroke, high blood pressure, type 2 diabetes and sleep apnea. To manage your weight and improve your overall health doctors recommends a diet rich in fibre. Foods high in fibre will fill you up without costing you too many calories.
9. Detoxify your liver: We’re constantly consuming toxins, whether it is from drinks or food, and your liver is responsible for clearing these toxins out of your body. Many doctors are skeptical of fad detox, saying they have the potential to do more harm than good. Luckily, one of the best and easiest things you can eat to help detoxify your liver is fruits-like apples.
10. Boast your immune system: red apple contains an antioxidant called quercetin. Recent studied have found that quercetin can help boast and fortify your immune system especially when you’re stressed out.
11. Prevent cataracts: Though past studies have been divided or the issue recent long-term studies suggest that people who have a diet rich in fruits that contain antioxidants like apples- are 10 to 15 percent has likely to develop cataracts.
12. Cancer: Scientists from the American Association for Cancer Research among others agree that the consumption of flavonoid-rich apples could help reduce your risk of developing pancreatic cancer by up to 23 percent. Researchers at Cornel University have identified several compounds-triterpenoids-in apple peel that have potent anti-growth activities against cancer cells in the liver – colon and breast. Their earlier research found that extracts from apple can reduce the number and size of mammary tumours in rates. Meanwhile, the National cancer institute in the U.S. has recommended a high fibre intake to reduce the risk of colorectal cancer.

References

Browning, F. (1999). Apples: The Story of the Fruit of Temptation. North Point Press.

Desmond, A. (1994). The World Apple Market. New York: Haworth Press

Elzebroek, A.T.G. & Wind, K. (2008). Guide to Cultivated Plants. Wallingford: CAB International.

Ferree, D. & Ian J. W. (1999). Apples: Botany, Production and Uses. United Kingdom: CABI Publishing.

Jules J., James, N., Cummins, S. K. & Minou, H. (1996). Fruit Breeding, Volume I: Tree and Tropical Fruits. New York: John Wiley & Sons, Inc.

Mabberley, D. J. & Juniper, B. E. (2009). The Story of the Apple: Crops & Gardening – Apples of Antiquity. Hobby Farms magazine

Yepsen, R. (1994). Apples. New York: W.W. Norton & Co.