Enhance Fruit Ripening Uniformity and Accelerate the Rutab Stage by Using ATP in 'Zaghloul' Dates during the Shelf Life

The Effect of Combining Post-Harvest Calcium Nanoparticles with a Salicylic Acid Treatment on Cucumber Tissue Breakdown via Enzyme Activity during Shelf Life

In the present study, an experiment was carried out on the postharvest of cucumber fruit during a 14-day shelf life. The aim was to assess the impact of calcium nanoparticles (CaNPs) blended with different concentrations of salicylic acid (SA) on the shelf life of cucumbers during the seasons of 2018 and 2019. The investigation further monitored the influences of CaNPs-SA on some physical properties of cucumber, including the percentage weight loss, color, and fruit firmness. In addition, chemical properties, such as total soluble solids (SSC%), total acidity (TA%), total soluble sugars, and chlorophyll pigmentation of the fruit skin, were assessed during a 14-day shelf lifeCell wall degradation enzymes (CWEAs) such as polygalacturonase (PG), cel-lulase (CEL), xylanase (XYL), and pectinase (PT) were also researched. In addition, the generation rates of H₂O₂ and O₂^•− were calculated, as well as the reduction of DPPH. The lipid peroxidation (malondialdehyde, MDA) and cell membrane permeability (IL%) of cell wall composites were also determined. CaNPs-SA at 2 mM suppressed CWEAs, preserved fruit quality, reduced weight loss throughout the shelf-life period, and reduced the percent leakage value. At this concentration, we also found the lowest levels of MDA and the highest levels of DPPH.

Impacts of Gum Arabic and Polyvinylpyrrolidone (PVP) with Salicylic Acid on Peach Fruit (Prunus persica) Shelf Life

Peaches are grown in many Egyptian orchards for local and global fresh market sales. The interior fruit tissue breakdown (IFTB), often resulting in decayed peaches, is a severe problem during marketing. Therefore, to minimize FTB of peaches, in this study, gum arabic (GA) and polyvinylpyrrolidone (PVP) were mixed with different concentrations of salicylic acid (SA) (0, 1, and 2 mM) and were applied as edible coating to extend the shelf life of peach fruits. Mature peaches were selected and harvested when peaches reached total soluble solid content (SSC: 8.5%) and fruit firmness of about 47 N. Fruits were coated and stored at room temperature (26 ± 1 °C and air humidity 51 ± 1%) for 10 days during two seasons: 2020 and 2021. Fruit coated with GA/PVP-SA 2 mM showed a significant (p < 0.05) inhibition in degrading enzyme activities (CWDEs), such as lipoxygenase (LOX), cellulase (CEL), and pectinase (PT), compared to uncoated and coated fruits during the shelf-life period. Hence, cell wall compartments were maintained. Consequently, there was a reduction in browning symptoms in fruits by inhibiting polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) activities. Thus, the fruit skin browning index showed almost no symptoms. The lipid peroxidation process and ionic permeability declined as well. The result suggests that, by applying GA/PVP-SA 2 mM as an edible coating, fruit tissue breakdown can be minimized, and the shelf life of peach can be extended up to 10 days without symptoms of tissue breakdown.

Calcium Ascorbate Coating Improves Postharvest Quality and Storability of Fresh-Cut Slices of Coscia and Abate Fétel Pears (Pyrus communis L.)

Flesh firmness is closely related to fruit ripeness and is typically a reliable indicator of shelf-life potential so it could be considered a crucial quality index for the determination of pear quality. Flesh softening after cutting could considerably affect consumer acceptance of fresh-cut pears (Pyrus communis L.). Indeed, mechanical stress (cutting, peeling, etc.) could lead to ethylene production that results in the hydrolysis of pectic substances in the cell walls. The effectiveness of an edible coating treatment on the physical-chemical, nutraceutical, and sensorial analysis was evaluated on two pear cultivars: the summer-ripening ‘Coscia’ and the late-ripening ‘Abate Fétel’, both harvested at their commercial ripening stage. Pear fruit slices were treated with calcium ascorbate, xanthan gum or HPMC coating and stored at 4 °C for 12 days. Weight loss, flesh firmness, soluble solid content, titratable acidity, ΔE color, browning surface, total polyphenol content, and antioxidant capacity were measured. Sensory analysis was carried out. Results showed that calcium ascorbate treatment applied to fruit slices significantly extended their shelf-life because it considerably inhibited browning and color changes in fresh-cut slices of both pear cultivars over seven days of storage. Furthermore, pear slices treated with calcium ascorbate revealed a higher antioxidant capacity and a lower content of total phenols during cold storage.

Utilization of Active Edible Films (Chitosan, Chitosan Nanoparticle, and CaCl2) for Enhancing the Quality Properties and the Shelf Life of Date Palm Fruits (Barhi Cultivar) during Cold Storage

Interest in edible coatings applications has progressively developed towards improving the quality and shelf life of climacteric fruits. This study aimed to investigate the influence of pre-harvest treatments (chitosan, chitosan nanoparticle, and CaCl2) on the physicochemical and quality attributes of Barhi date palm fruits during storage periods. Different pre-harvest treatments (control, chitosan 1, 2, and 3 g/L, CaCl2 1, 2, and 3 g/L, nano-chitosan 1, 2, and 3 cm3 /L) were applied. The results showed that all treatments were effective for enhancing the fruit quality, with increasing total soluble solids and total sugars, decreasing weight loss, discarded total acidity, and total soluble tannins compared to the control treatment. Additionally, the results revealed that the highest percentage of TSS was obtained in control fruits (35.78%). Meanwhile, the lowest mean values were obtained from chitosan nanoparticle at 3 cm3/L (33.91%). Treatments with chitosan nanoparticle at 3 cm3/L and CaCl2 at 3 g/L gave the statistically highest values of total tannins (0.225 and 0.220, respectively). The optimal treatment involved spraying the fruit with 3 cm3/L of nano-chitosan or 3 g/L of CaCl2 to increase the fruit quality and the shelf life of Barhi dates. The results indicated that weight loss was negatively linked with the moisture content and firmness, while decay had a strong positive relationship with the Rutab index and a negative correlation with the moisture content. Furthermore, the Rutab index was negatively associated with the total tannins and total chlorophyll.