The grape is a berry, fruit of the vine, (climbing plant) its scientific name is Vitis vinifera. In terms of its nutritional value, the fruits contain an average value of sugars ranging from 11.3g/100g of fruit, with the white grape having the lowest concentration, up to 21.3g/100g of the burgundy grape, the rest of the named varieties range between 16.7 and 18.1 g/100.
The white grape is the one that provides the fewest calories (43 calories) and the burgundy is the most energetic (82 calories) (Peruvian Tables of Food Composition, Collazos).
Among the minerals it contains are calcium and phosphorus, while the vitamins provide small concentrations of complex B and vitamin C. According to the tables published in Eroski Consumer, they provide significant amounts of potassium (250mg green grape and 320mg black grape ) and magnesium (10mg the green one and 4mg the black one), the contribution of concentrated fiber in the skin and seeds helps to facilitate bowel movements.
Every day we should consume 3 to 5 units of fruit per day. When choosing grapes, the recommended amount is 100 grams, which is equivalent to a bunch of 10 to 12 grapes. These can be consumed at any time of the day, however, diabetic patients or people with imbalances in their glucose or insulin should prefer them during the day.
Its characteristic smell and flavor are conferred by organic acids (citric and malic) and phenolic compounds (anthocyanins, tannins, and flavonoids) with a powerful antioxidant capacity, present mainly in the skin. The green varieties are richer in tannins giving them an astringent flavor, while the red, maroon and black colored varieties contain more resveratrol, a studied flavonoid to which preventive properties are attributed in terms of cardiovascular health (vasodilator, decreases platelet aggregation inhibits the oxidation of LDL cholesterol).
A study published in the specialized journal Nutrition Reviews showed that grapes help make the arteries more flexible and properly manage LDL or “bad cholesterol”. While another study published in The American Journal of Clinical Nutrition concluded that consumption of Concord grape juice helps lower night-time blood pressure (a healthy indicator of blood pressure regulation). It also improved blood sugar levels.
When buying them, choose that bunch that, when lifted and shaken, does not detach the berries (the grapes), the trunk must maintain its green color. The clusters must be solid and the fruit firm, with smooth skin and uniform color and size.
To preserve them, you can refrigerate them where they will last about 15 days or you can keep them hanging inside bags in the open depending on the point of maturity. Although their skin is waterproof and it is preferred to peel them, they should be washed with plenty of water before consumption.