| Electronic Journal of Biotechnology
ISSN: 0717-3458 |
| © 2000 by Universidad
Católica de Valparaíso -- Chile |
Pre- and postharvest factors
affecting fresh produce quality, nutritional value, and implications for
human health
Adel A. Kader
Department of Pomology
University of California
Davis, CA 95616, USA.
Fresh fruits and vegetables
play a very essential role in human nutrition and health, especially as sources
of vitamins, minerals, and dietary fiber. Other constituents that may lower
risk of cancer, cardiovascular disease, and other diseases include carotenoids,
flavonoids and other polyphenols, phenolic acids, and other phytonutrients.
Nutritional value varies greatly among commodities and cultivars of each commodity.
Using plant breeding and biotechnology approaches it is possible to develop
genotypes that have enhanced nutritional quality and improved flavor quality
to encourage consumers to eat more fruits and vegetables (at least five servings
per day). This can have a major positive impact on human health and should
be given high priority in research and extension programs worldwide. Climatic
conditions, especially temperature and light intensity, have a strong effect
on the nutritional quality of fruits and vegetables. Soil type, the rootstock
used for fruit trees, mulching, irrigation, fertilization, and other cultural
practices influence the water and nutrient supply to the plant, which can
affect the composition and quality attributes (appearance, texture, taste
and aroma) of the harvested plant parts. Maturity at harvest and harvesting
method influence the commodity’s quality and extent of physical injuries.
Delays between harvest and consumption or processing can result in losses
of flavor and nutritional quality. The magnitude of these losses increases
with exposure to temperatures, relative humidities, and/or concentrations
of oxygen, carbon dioxide, and ethylene outside the ranges that are optimum
for each commodity during the entire postharvest handling system. Furthermore,
processing and cooking methods can greatly affect the nutritional value of
fruits and vegetables. |
