Caryocar brasiliense, known as Pequi or "souari nut", like its
congeners, is an edible fruit popular in some areas of Brazil,
especially in Brazil's center-west region.
The pequi tree grows up to 10 m (30 ft) tall. It is common in
central Brazilian cerrado habitat from southern Pará to Paraná and
northern Paraguay. Its leaves are large, tough, hairy and palmate,
with three leaflets each. Unlike most other cerrado trees, it bears
flowers in the dry winter months, approximately July to September.
The yellowish-white flowers are hermaphroditic and bear many
stamens; they somewhat resemble a huge pale St John's Wort flower (a
distant relative among the Malpighiales). There are often two dozen
or more flowers per inflorescence.
Pollination is mainly by bats, and as usual in such cases the
flowers do not have a pleasant smell but produce copious thin
nectar. Flowers open in the evening and produce nectar throughout
the night, ceasing in the early morning. As it seems, each night's
last nectar, produced around dawn, is richer in sugars than that
produced in the night, though it is much less in quantity already.
Moths, nocturnal wasps and ants also visit the flowers at night; the
former two might also do some pollinating but they are not known to
be of major importance. During the day, the flowers are visited by
bees and wasps which feed on remaining pollen. From dusk to the
cessation of nectar production, hummingbirds may visit the flowers.
While most of them only do this opportunistically, some species –
e.g. the Fork-tailed Woodnymph (Thalurania furcata) and in
particular the Glittering-throated Emerald (Amazilia fimbriata) –
appear to visit pequi tree flowers on a regular base. More
significantly, visits by small "tanagers" of the Thraupidae and
Cardinalidae around dusk are noted. In particular species like the
Guira Tanager (Hemithraupis guira), White-lined Tanager (Tachyphonus
rufus) and the Palm (Thraupis palmarum) and Sayaca Tanagers (T.
sayaca) seem to be quite fond of pequi flower nectar and spend
considerable time feeding on it when available. But even
Curl-crested Jays (Cyanocorax cristatellus) have been observed to
hang about flowering pequi trees at daybreak, though perhaps not
just for the nectar, considering many insects attracted by it
earlier would still be around on the tree. As the stigmata dry out
at daybreak, it is not clear whether birds, particularly "tanagers",
play a role in pollination also or are merely making use of an easy
early-morning snack, particularly considering that during the
flowering season of C. brasiliense, little such food is available.
Fruits start off dark purple, turning olive green and finally
buffy green as they ripen, taking about 5–6 months[verification
needed]. Ripe fruits are about the size of an orange. They resemble
a mangosteen (another distantly related member of the Malpighiales)
in having a few (usually 1-4) segments of pulpy pericarp inside the
skin, yellow and with a typical strong taste and smell mixing sweet,
fruity and cheesy aromas; this is derived mainly from volatile ethyl
esters. Embedded in the mesocarp is a light-colored seed enclosed in
a blackish shell covered with thin and tough woody spines, though
spineless individuals exist in the wild. Both the mesocarp and the
seed are edible for humans as well as many animals, including
usually carnivorous species like the Yellow-headed Caracara (Milvago
Use by humans and status
Pequi pulp is a very popular food in Goiás and Minas Gerais, eaten
by itself raw or prepared or used as an ingredient in cooking or to
flavor beverages. Pequi with rice and chicken is especially popular
among locals; tourists often find the unique rich flavor of pequi
too strong and the dish too filling for their taste. Pequi pulp will
tarnish silver cutlery and if eaten raw the fruit is best enjoyed
out of hand. Care must be taken to gently scrape the pulp off the
pit using one's teeth: The spines easily detach and when stuck in
the gums can be highly painful and difficult to remove.
The pits with spines and remaining pulp can be left to dry in the
sun for two days or so. Afterwards, the spines can be scraped off
with a knife or stick, and the pit can be cracked open to extract
the seed. From the latter, the edible pequi oil is extracted
commercially. They can also be roasted like peanuts and eaten with
salt as a rich snack; in fact, if anything they are more popular
than Brazil nuts locally.
Nearly every part of the tree is usable for food, medical or
construction purposes. Pequi occupies an important role in the
culture of indigenous people in Brazil's Cerrado region.
Traditionally, rural Brazilians plant pequi trees around villages;
the seed take a long time to germinate so that new trees must be
planted ever so often for the supply not to cease. Demand for the
fruit has risen in recent decades while habitat has been destroyed,
putting the stocks under strain. One report writes:
"The pequi is the main symbol of this de-structuring of the
economy. The pequi is habitually consumed by the population in the
Cerrado zone and is deeply rooted in the regional culture and
cooking. For the Mineiros, the Cerrado inhabitants of Minas Gerais,
the pequi does not belong to anyone, because it belongs to all.
Therefore, they maintain their ancestral right to take it wherever
it is, in public or private land, fenced in land or unfenced land,
etc., wherever it is, the pequi was always "accessible" to the
regional society. Since the sixties, due to logging and installation
on a wide scale of eucalyptus plantations, the pequi and all that it
represents are under a serious threat. So much so, that at the
market in Curvelo we did not find any pequis for sale. Some trades
people commented on the difficulty they have in obtaining this
fruit, which was previously so accessible."
Also, given the importance of bats and perhaps birds for
pollination, removal of native woodland is liable to have long-term
negative impacts on fruit yield even if no C. brasiliense trees are
physically harmed. Conserving pollinator habitat is probably crucial
for rich yields of the valuable fruits and other produce.