Unlike other members of the myrtaceae family, eucalyptus or cloves , guava is not very aromatic.
This small tree of 3 to 10 m, with very hard wood, is native to tropical America .
It was introduced very early by Spanish navigators in the Philippines or Portuguese in India; it is now pantropical.
Its robustness and its ease of dissemination (by birds) make it consider as a plant plague in many islands of the Pacific where it smothers native vegetation on inaccessible mountain slopes.
In tropical America, it is a plant that invades abandoned agricultural land (felled) before being itself covered by higher vegetation which limits its development.
Birds, wasps, monkeys or humans seek its fruit: the guava.
It is a small round or ovoid fruit 4 to 10 cm in diameter that turns green to yellow when ripe; it contains a sweet pulp of pink to red color, including many hard seeds, yellow or brown, kidney-shaped from 2 to 5 mm.
CHEMICAL COMPOSITION AND PROPERTIES
All parts of the tree are rich in TANNINS, especially the bark (10%) but also the leaves, roots and epicarp of the fruit.
The average composition of the guava endocarp without seeds reveals 10 to 15% of sugars and a lot of VITAMIN C (25 to 500 mg per 100g depending on the fruit, their maturity and the variety), it is on average 2 to 5 times more than orange juice.
Guava pulp contains also VITAMIN A, iron, calcium and phosphorus.
They are a by-product of guava juice.
The small seeds are lightly roasted to lower humidity, increase oil content percentage and decrease anti-nutritional compounds.
Average composition (dry weight basis) :
Proteins : 7%
Lipids : 19%
Glucids : 23%
Crude fibers : 43%
Water : 4%
Mineral ash : few %
An EDIBLE OIL can be chemically extracted from the roasted seeds, average composition :
Saturated fat : 14%.
Unsaturated fat : 86%, with a very high percentage of linoleic acid (omega 6) , with cosmetic properties.
Fresh guava is a good source of VITAMIN C.
The fruit is digestible when peeled and does not have the acidic character of citrus fruits but it does not keep very well.
Concentrated and dehydrated guava juice is a source of vitamin C which was used during the 2nd world war to improve the rations of the American soldiers.
It is now found pasteurized in many countries; guava pulp without seeds is used to make excellent jams or jellies.
In traditional and herbal medicine, leaves, bark, young twigs or green fruits are used to obtain an ASTRINGENT decoction:
Example: 10 to 20 leaves in 1/2 to 1 liter of water, boil and reduce by half by boiling.
It is useful in case of:
DIARRHEA (one cup twice a day).
ANGINA, tonsillitis (gargling).
INFECTED OR OOZING DERMATOSIS (including erysipela) in bath or application.
LEUCORRHEA, postpartum delivery (vaginal injection or bath).
GUAVA SEED OIL
Cosmetic uses : skin protection.
Culinary uses : better if mixed with another oil with a much lower content in linoleic acid like canola oil, palm oil .
The guava tree is a plant from the tropical-equatorial region but there are varieties that adapt to the warm regions of temperate countries, for example: Florida, California, southern Spain, Greece.
In colder regions, the guava tree must be protected during the winter and is then generally planted in pots.
Propagation can be done by seeds, by root shoots, by cuttings.
You can graft the guava tree to keep an interesting variety, on another guava tree or on a neighboring species more resistant to diseases such as coronilla (Psidium friedrichsthalianum).
In hot regions the guava tree can become invasive.
GUAVA VITAMIN C and tannins
Guava tree is very common in tropico equatorial regions, its fruit, guava, is eaten locally or exported in the form of juice or jam, it contains a lot of vitamin C.
The leaves, the bark contain tannins which are used (in decoction) to treat all the disorders which require an astringent, for example: infection or inflammation of the mouth, skin or genital infections or diarrhea.
Copyright 2020 : Dr Jean-Michel Hurtel