Avocado - Tropical and Subtropical Fruits: Postharvest Physiology, Processing and Packaging - page 420

23
Avocado

Lidia Dorantes-Alvarez, Alicia Ortiz-Moreno and Felipe Garcıa-Ochoa

INTRODUCTION
Avocado ( Persea americana Mill.) is different from other
fruits due to its high content of lipids and phytochemicals. It
has a fatty acid pattern similar to that of olives, but they dif-
fer in the matrix that gives the characteristic textural rigidity
to each fruit. Avocados have a tough texture and become
very soft when they are overripe. The excessive softening
of overmature avocado induces a higher molecular mobility
that accelerates some biochemical changes that are unde-
sirable for the consumer. The desirable characteristics of
texture, composition, color, and flavor of ripe avocado last
just a few days at tropical temperatures (25 ◦ -35 ◦ C); fur-
thermore, the pulp has high potential of browning during
the maturation progress.
The challenges of the preservation of the quality charac-
teristics of avocado together with the discovery of its bene-
fits to human health have given an increased impetus to re-
search around the world, particularly in avocado-producing
countries. In the past 10 years, more than 30 papers have
been published on the topic of phytochemicals in avocado
fruits and extracts. In addition, about 20 patents have been
generated mainly about operations and processes dealing
with products derived from avocado.

exporting, and -importing countries. Mexico is the lead-
ing producer with 1.10 MMT (about 29% of the world
total), followed by Chile, the Dominican Republic, Indone-
sia, and Colombia. Mexico is also the top avocado ex-
porter, while the United States is the leading importer of
avocados.

PRODUCTION, VARIETIES, AND HARVESTING
Botanically, avocados can be classified into four strains:
West Indian, Guatemalan, West Indian-Guatemalan hybrid,
and Mexican (Evans, 2006). The well-known 'Hass' avo-
cado is a Mexican strain and grows primarily in Mexico
and California. Avocados of the other three strains grow in
Florida, Puerto Rico, the Dominican Republic, and other
Caribbean countries, where the high humidity is not suit-
able for 'Hass.' Many varieties have been derived from
these strains; for example, about 60 varieties of avocados
are grown in Florida, where fruit is harvested from May to
February (Wang et al., 2010). There are variety-dependent
differences among the characteristics of the fruit, includ-
ing size, weight, and thickness of the peel. For example,
the 'Hass' variety (Fig. 23.2) contains more pulp than the
Mexican type. Also, the thickness of the peel is greater than
others, which makes this variety more resistant to pests.
During the production, special attention should be paid to
the nutrition and pest control of avocado orchards, partic-
ularly when producing fruit for organic and international
markets. California-grown avocado varieties are shown in
Table 23.2.
A unique feature of avocados is that the fruits mature
in the tree and ripen after harvest. Harvesting of the fruit

WORLD PRODUCTION AND TRADE
The 2010 world total production of avocado was 3.84
million metric tons (MMT), which represented about
92% increase as compared to 1990. The avocado pro-
duction has seen a consistent increase since 1990; 36%
and 41% during 1990-2000 and 2000-2009, respectively
(Fig. 23.1). Table 23.1 shows leading avocado-producing,-