Agriculture Reference
In-Depth Information
satisfactorily at 20-30°C, but moisture loss and shrinkage are rapid at these
higher temperatures. It is critical to keep relative humidities during storage
below 70% to avoid the growth of surface moulds and prevent root emergence.
As with onion, sprouting can be prevented by spraying plants with maleic
hydrazide while bulbs are maturing but with leaves still green, or by treating
bulbs with gamma radiation after harvest.
Research in Scandinavia has investigated how autumn-harvested leeks can be
stored through the winter (Hoftun, 1978a, b). More recent research on the
storage of leeks harvested in the early spring in the UK has broadly confirmed
the Scandinavian findings on the best regimes for preserving high-quality leeks.
In contrast to onion and garlic bulbs, the pseudostem and lower part of the
green leaves, which are normally harvested from leek, are not naturally
dormant. Table 7.2 and Fig. 7.16 show that the respiration rate of leeks increases
progressively and rapidly as temperature increases. The rate of deterioration in
store shows a parallel and rapid increase with temperature.
During storage, leeks lose weight by evaporation, by respiration and
because the leaves, particularly the green parts, yellow and must be trimmed
Fig. 7.16.
The accumulated CO
2
production of leeks after storage at a range of
constant temperatures (from Hoftun, 1978a. Courtesy of
Meldinger fra Norges
Landbrukhogskole
).
