COMMON GRAPE VINE
Many Vitaceae are tendril vines or climbing shrubs whose fruits are berries.
They are well represented in arm regions.
The genus Vitis comes from the northern hemisphere and is found from America to Eurasia to the Far East.
Vitis vitifera is the most important species, farmers-winemakers have selected thousands of varieties (grapes), but originally grape vine was a European wild plant of river banks, mountain slopes and forests clear.
It is a tendril vine whose base lignifies strongly and which can reach a great age.
The inflorescence is in a cluster and the fruit, the grape, is a watery berry that varies in size and color depending on the cultivar.
The grape at ordinary temperature does not keep long, it can be dried or its juice left to ferment which can thus be kept for quite a long time in the absence of air, this is vinification.
The appearance of the vine is quite variable, some varieties (eg, V. vinifera var. tinctoria), have dark blue almost black fruits (the pulp is red), and their leaves turn from green to red in autumn, this is the officinal variety.
The majority of vine species of the genus Vitis are found in temperate and cold zones, but some have adapted to hot climates (eg, V. caribbea = V. tillaefolia in the West Indies).
In North America (USA and Canada) the main species are V. labrusca (the fox grape), V. riparia, V. rupestris and V. berlandieri; in the Far East, wild grapes are called V. amurensis (the Amur River region) and V. coignetiae (Japan and the Sakhalin peninsula).
Species originating in North America have been used to renew French vineyards destroyed by phylloxera (rootstock or hybridization).
Certain species of Vitis other than Vitis vinifera probably have medicinal value, but it is Vitis vinifera which is part of the French pharmacopoeia.
The interesting parts for health are: the fruit and its juice, the seeds, the buds and the leaves of red cultivars vine.
CHEMICAL COMPOSITION AND PROPERTIES
Fresh grape juice is a little variable in its composition depending on the geographical area and the varieties, we can nevertheless give an average composition:
- 80% water,
- 18% carbohydrates,
- 1% protein, 20 mg/ 100g of Ca, a little iron, provitamin A, 5 mg/100g of vitamin C, a little vitamin of group B.
During vinification (and simplifying a bit) the yeasts (naturally present on the surface of the grapes or selected and artificially integrated into the fermentation tank) transform the simple sugars in the juice (glucose, fructose) into ethyl alcohol (ethanol) and bacteria modify the composition of organic acids (tartaric, malic, lactic, it is the malolactic fermentation).
The final product (the wine), when the fermentation has naturally stopped due to the increase in the concentration of alcohol (ethanol), presents a very variable and very complex composition where ethanol dominates (between 50 and 150 g /l) with glycerol (4 to 20 g/l) and organic acids (5 to 20 g/l).
There are also protein derivatives, volatile substances that give the aroma, the "bouquet" (aldehydes and fatty acid esters), and many phenolic compounds (acids-phenol, pigments (flavonoids, anthocyanins) tannins) ; the vitamins have almost disappeared.
The chemical characteristics of the wine depend on the grape variety, the geographical area and the winemaking process.
In the absence of air, the wine keeps fairly well, especially if the quantity of ethanol is high (alcoholic degree equal to or greater than 11-12).
RED CULTIVAR VINE LEAF AND GRAPE
There is a high concentration of red pigments (anthocyanosides ) and their derivatives as well as phenolic compounds and tannins (proanthocyanidols and gallic acid derivatives)
- in the envelope of the grape (especially the dark blue colored varieties),
- in its pulp when it is red,
- and in the leaves (especially of the tinctoria variety) .
From the seed itself, an edible oil and condensed tannins (proanthocyanidols) are extracted.
Average composition of seed oil in fatty acid and in percentage:
palmitic acid (C16): 5.5 to 11%
stearic acid (C18): 3 to 6%
oleic acid (C18-1): 12 to 28%
linoleic acid (C18-2): 58 to 78%
alpha linolenic acid (C18 -3): less than 1%
Note the high percentage of unsaturated fatty acids dominated by linoleic acid (omega 6).
The proanthocyanidol tannins present in the pulp, envelopes, leaves and seeds of grapes are considered good protectors of blood vessels, they trap free radicals and inhibit many enzymes (this can of course give positive or negative effects) .
The simplest proanthocyanidins (dimers) increase the resistance of the capillaries with the effect of reducing oedemas.
Excessive consumption of tannins can however be harmful (possible risk of digestive carcinogenesis).
FLAVONOIDSRed or purplish pigments (anthocyanins which give color to red and rosé wine) and their derivatives are also vascular protectors which reduce the permeability of capillaries by increasing the resistance of the walls.
Resveratrol is a natural phenolic compound of the stilbene family (therefore able to interact in the metabolism of sex hormones) present, but irregularly, in many plants including the grape vine and its grapes.
This molecule is probably synthesized by the plant in response to stress such as infection by a fungus.
It is therefore a potentially very active defense substance, it is also present in small quantities.
It is found in the envelope of the grape (the "skin" of the grape, frequent site of infections by fungi).
During vinification, resveratrol passes into the wine especially when the maceration is prolonged, that is to say for red wines, but much less for white wines.
Resveratrol (especially its trans- isomer), easily assimilated by the digestive tract, seems to have many interesting properties in medicine and which combine to:
- limit degenerative cardiovascular disorders (myocardial infarction, stroke),
- alleviate the disorders physical symptoms of obesity and disorders linked to an abnormal increase in blood cholesterol,
- stabilize type 2 diabetes and promote weight loss,
- slow down or prevent the appearance of cancer.
GRAPE AND WINE, RESVERATROL, THE FRENCH PARADOX
Fresh grapes are a source of simple sugars and vitamins (but also in some cases pesticides).
Wine, an alcoholic beverage, is also a food (the ethanol is partly digested).
The reasonable consumption of red wine seems to protect, in the long term, against the cardiovascular disorders related to the aging of the blood walls and the deposit of atheroma plaques (arteriosclerosis).
This is what the english speaking countries call the "French paradox": a diet rich in animal fat which should promote the early onset of cardiovascular disorders when, in fact, we observe a lower rate of ischemic accidents (myocardial infarction or stroke) than in other populations of rich countries (probable long-term action of the many phenolic derivatives of wine: pigments and tannins as well as resveratrol when present in wine).
The significant use of pesticides in modern viticulture calls into question the protective nature of wine on health.
It is better to drink wines made from vines managed according to the principles of "reasoned" or organic agriculture.
In addition, the wine is most of the time stabilized to avoid the natural evolution towards vinegar by the addition of a variable quantity of sulfur derivatives (sulphites) which can cause digestive disorders (gastric burns), migraines orallergic reactions type.
RED GRAPE VINE LEAF, PROTECTION OF BLOOD VESSELS
RED GRAPE vine extracts are commercially available: freeze-ground powder, leaf powder, an average dosage: 500 mg to 1 g of leaf powder per day.
It is prescribed in circulatory disorders linked to venous stasis (varicose veins, hemorrhoids) but also in arteriolar disorders linked to age or diabetes.
GRAPE SEED EXTRACTS, VARICES, EDEMA
Grape seed extracts are also vasculo-protective, purified extracts of proanthocyanidol dimers are found in drugstores, average dosage, 300 mg per day.
Recent studies show that these seed extracts slow the development of certain cancers.
They prevent or limit metastases, in particular those of breast cancers (experiments on mice).
These extracts are also useful for reducing edema secondary to breast cancer treatments (surgery and radiotherapy).
VITIS VINIFERA GRAPE BUDS, ARTHROSIS and INFLAMMATION
Gemmotherapy recommends the glycerine maceration of buds in 1 decimal (1 D) of Vitis vinifera in the treatment of osteoarthritis in young subjects in association with Ribes nigrum and Pinus montana.
It is a classic treatment that must be continued for about 3 months, example of dosage:
1D glycerinated macerations of Vitis vinifera, Ribes nigrum, Pinus montana buds:
50 drops of each maceration once a day for 3 months, one in the morning, the other at noon and the third at the end of the day.
GRAPESEED OIL OMEGA 6Grapeseed oil, which contains a lot of linoleic acid (omega 6), can be used as a seasoning and for frying, but it is unbalanced because it is low in omega 3.
THE VINE, THE GRAPES, THE WINE, THE RED VINE LEAF
VITIS VINIFERA gives us the grape, a source of sugar and vitamin C, the wine (and the “French paradox”), but also the leaf (of the strongly tinted variety ) which provides the body with tannins and pigments, vascular protectors, anti-inflammatories and free radical scavengers.
An edible oil rich in essential fatty acids is extracted from grape seeds.
Copyright 2022 : Dr Jean-Michel Hurtel