Agriculture Reference
In-Depth Information
16.10
ESSENTIAL OILS
A new approach to control the postharvest pathogens, while maintaining
fruit quality as an alternative to chemical fungicides is by the applica-
tion of essential oils to fruit. This approach eliminates the need for syn-
thetic fungicides, thereby complying with consumer preferences, organic
requirements and reducing environmental pollution. Essential oils (EOs)
are volatile, natural, complex compounds characterized by a strong odor
and are formed by aromatic plants in different parts (flowers, buds, seeds,
leaves, twigs, bark, herbs, wood, fruits and roots) as secondary metabo-
lites. These are registered food grade materials and have the potential to be
applied as an alternative treatment to control post harvest decay of fruits.
An important characteristic of EOs and their components is their hydro-
phobicity, which enables them to partition in the lipids of the bacterial cell
membrane and mitochondria, disturbing the structures and rendering them
more permeable. As a result, damage of membrane proteins and depletion
of proton motive force takes place. Leakage of ions and other cell con-
tents can then occur which after attaining extensive loss of cell contents
or of critical molecules and ions lead to death of bacterial cells. A number
of essential oil components have been identified as effective antibacterial
agents, for example, eugenol, carvacrol, thymol, menthol which can be
used in controlling postharvest diseases of several fruits like apple, peach,
sweet cherry, strawberry, grape, citrus, mango, etc. (Regnier et al., 2008)
(Table 16.2).
TABLE 16.2
Essential Oils Used for the Control of Postharvest Diseases of Fruit
Essential oil
Major component(s)
Bacteria
Fruit crops
P. expansum, M. fruc-
tigena, B. cinerea, P.
vagabunda
Clove oil
Eugenol
Apple, grape
P. italicum, B. cinerea, R.
stolonifer
Orange, straw-
berry
Mint oil
Menthol
B. cinerea, R. stolonifer,
M. fructicola
Strawberry, grape,
sweet cherry
Thyme oil
Thymol, carvacrol
Cinnamon oil
Cinnamaldehyde
Natural flora
Kiwifruit
C. gloeosporioides, P.
expansum, B. cinerea, R.
Stolonifer
Lemongrass
oil
Citral
Mango, peach
 
Search WWH ::




Custom Search