EXTENDING THE KHALAL STAGE OF “ZAGHLOUL” DATES BY UTILIZING THE MODIFIED PACKING METHOD AND ANTIETHYLENE COMPOUNDS

Rezumat

The present study was conducted in order to increase the availability of "Zaghloul" dates favored
for consumption at the khalal stage. During the two successive seasons 2017 and 2018, dipping postharvest
treatments and the modified packing method were applied to extend the khalal stage of "Zaghloul" date palm
fruits. The treatments included the control (water), the control with wood shavings, CaCl2 (2%, w/v), glycerol (1
%, v/v), CaCl2 plus glycerol, AVG (50 ppm), putrescine (2mM) and AVG followed by putrescine, then, the
treated fruits with the substances treatments were embedded in layers of the wood shavings. All packed dates
stored under cold storage conditions (4oC and 90 -95 % relative humidity). The results revealed that all
treatments were able to reduce weight loss, fruit decay, electrolyte leakage, total soluble solids percentages and
rutab score. More drastic reduction in these characteristics was found with the application of AVG when
followed by putrescine in the presence of wood shavings. While, there was no clear trend for treatments effect
on fruit total acidity content. Treated dates with CaCl2 or AVG when followed by putrescine had the highest
values of total sugars. On the contrary, anthocyanin content in dates peel slightly increased by different
treatments. This study provided evidence about the feasibility of using the combination of AVG with putrescine
or CaCl2 plus glycerol in the presence of wood shavings to extend the khalal stage of "Zaghloul" dates and
maintain their quality on a large scale.