Other than Antarctica, grapes are grown on every continent of the world. Grapes (Vitis vinifera) are actually classified as berries. They come in round or oval shapes and have juicy semi-transparent flesh inside. They grow in clusters ranging from six to three hundred fruits with most common varieties being green, red or purple/black in colour. They have a sour taste when not yet ripe due to the malic acid they contain, but as they ripen the content of the acid decreases and they become sweet tasting. They have to be hand-picked as machines tend to bruise them easily. Grapes serve three primary uses: for wine production, as dried fruit (raisins) and as fresh fruit.
The fruits develop on robustly climbing vines which can reach the height of fifteen to twenty five metres if left without pruning. The deciduous vine (leaves lost in winter) has flat green leaves that are lightly lobed and have saw like edges. The thin snake-like tendrils secure the vine by twisting around any available structure and support the plant as it climbs higher. Wild grape vines are able to even climb over trees and block sufficient sunlight from reaching the trees to kill them. The flowers produced develop in clusters and are small, green and have a fragrance. Clusters of grapes develop from the fertilized flowers.
History of Grapes
Wild grapes have been around almost as long as civilization itself. They are believed to have originate somewhere in East Europe, Middle East or North Africa. Some evidence suggests that grapes were grown as early as 6500 B.C in the Neolithic era. Around 4000 B.C.E. grape cultivation extended into Asia Minor and along the Nile Delta of Egypt.
The Hittites were responsible for spreading grapes westward as they journeyed to Crete, Thrace and Bosporus as long ago as 3000 B.C.E. The Phoenicians and Greeks promoted the growth of the fruit to Sicily, Carthage, Spain and France. The Romans took charge and spread it further throughout all of Europe.
Man learned of the art of fermentation and converting grapes into wine in the Stoneage. Egyptians were the first people to produce wine. However at that time it was not used for social drinking. It was mainly employed in religious ceremonies and temple rituals. The Greeks and Romans grew grapes for use as substitutes for sugar. They produced syrups like passum, and sapa, which were then used to flavour dishes. Syrups made from grapes are still common in Levant regions and Turkey.
Towards the end of the Roman Empire, wine production was mainly associated with monasteries. Later on its use went beyond the religious boundaries and it became a part of the social culture. With this the demand for grapes continuously grew from the 16th century to date. King Hammurabi of Babylon is believed to be the initiator of the very first liquor law when he set down the rules for trading wine in 1700 B.C.E.
Health Benefits of Grapes
Grapes are only tiny in size but they are big when it comes to delivering health benefits. While all varieties of grapes are good for health, the darker coloured ones tend to offer greater benefits. This is because grapes with darker skin, namely red and purple/black ones have a higher content of resveratrol. This polyphenol found in grape skin is a natural anti-pathogenic that is believed to block cell signals through what is known as the Writ pathway. This pathway is connected with more than 85% of sporadic colon cancers. Reveratrol has also be shown to be effective in treating skin and gastrointestinal cancers in addition to suppressing tumours of lung, breast, prostate and leukaemia.
Resveratrol also works to clean out brain damaging plaques and free radicals found in patients suffering from Alzheimer’s disease. Grapes delay the onset of degenerative neural diseases. According to a study published in the British Journal of Nutrition, grapes can even improve brain function in people who already have minor cognitive impairment.
Grapes also contain the powerful bioflavonoid, quercetin which works with vitamin C to accelerate the immune system to combat infection, inflammation, and cancer in addition to providing relief from anguishing pain for arthritis and gout patients. Grapes added to a diet help to maintain alkalinity. When blood and urine are a little more alkaline, acidic wastes are removed from the body more easily leading to fewer attacks of painful rheumatoid arthritis and recurring gout symptoms. Uric acid crystals that form with reduced kidney function dissolve easily in alkaline urine and are eliminated from the body thus averting their deposit in joints of gout patients.
The University of Michigan Cardiovascular Centre made grape powder mixture using red, green and black grapes inclusive of seeds and skin. They added this powder to the diet fed to the rats. After eighteen weeks the rats given the grape enriched diet had less inflammation, lower blood pressure, better heart function and fewer signs of heart damage compared to the rats that had the same diet without grape powder enrichment.
Nutritional Value of Grapes
Grapes have an amazing composition of phytonutrients like poly-phenolic antioxidants, vitamins and minerals. They are low in saturated fat, sodium and cholesterol. They are a good source of Vitamin K and C. They also have small amounts of vitamin A and E, niacin, folates, pantothenic acid, pyridoxine, riboflavin, and thiamine. They contain small amounts of the electrolyte potassium and trace amount of sodium. In the mineral department they are a good source of copper, small amounts of calcium, iron, magnesium, manganese, and trace amount of zinc.
The large variety of phytonutrients in grapes make them a powerhouse for good health. While no single variety contains all of the mentioned micronutrients, grapes in general provide Flavanols like catechins, epicatechins, and procyanidins, Flavonols like quercetin , kaempferol , and myricetin. They also contain important Carotenoids like beta-carotene, lutein, zeaxanthin and Phenolic Acids such as caffeic acid, coumaric acid, and ferulic acid.
Uses of Grapes
Freshly purchased grapes can stay in the refrigerator for up to 5 to 7 days. Before eating them, make sure to wash them thoroughly to remove any possible pesticide remains. For best flavour, grapes should be served slightly chilled. But, grapes are not for just eating out of hand, you can make jams, jellies and preserves out of them, use them in baking, or fresh salads, juice them on their own or in combination with other fruits. For long term preservation grapes can be canned, or frozen.
Frozen grapes make a great summertime treat. Just remove the grapes from the vines and after washing, spread them on a cookie sheet to freeze. Frozen in this way they can be eaten as a snack or used in salads or added to yogurt like fresh grapes. They keep their shape remarkably well when defrosted. Juiced grapes, sweetened lightly with honey can make great popsicles.
A number of related conditions including high blood sugar, blood pressure, extra fat around waist, elevated cholesterol that lead to chronic diseases are known as metabolic syndrome. Researchers at the University of Michigan presented a paper at the Experimental Biology Conference showing grapes protect damage to organs linked with advancement of metabolic syndrome. They believe the polyphenols in grapes are responsible for this effect. The team claims consuming grapes of different coloured varieties can have major impact on metabolic syndrome.
Macular degeneration is a condition where the centre of the retina, called the macula, deteriorates and is one of the main causes of blindness in the aged. A study published in Free Radical Biology and Medicine claims that consumption of grapes during one’s lifetime can aid in slowing or preventing this age-linked condition. It is thought that the action of antioxidants in grapes is the cause of this protective effect. Antioxidants form a protective shield to protect against repeated exposure to high intensity sun light and may avert blindness.
University of Illinois researchers reported the resveratrol found in grapes halts the growth of tumours at all stages, while France’s Liver Research Study Group says that resveratrol stops liver cancer by blocking tumour cell invasion.
Complutense University of Madrid, Spain researchers extracted Grape Antioxidant Dietary Fibre (GADF) from seeds and skin of red grapes and added it to meals of 34 adults. After sixteen weeks, it was found that the group taking GADF showed a five percent decrease in blood pressure, and a fourteen percent decrease in cholesterol. High cholesterol patients who consumed GADF also registered a reduction of over fourteen percent in total cholesterol and over eleven percent decrease in LDL (bad) cholesterol.