Babak ValizadehKaji; Saied Maleki; Ahmadreza Abbasifar
Abstract
Table grape is a non-climacteric fruit with a short shelf-life. The current study aimed at applying specific treatments to prolong its shelf-life and maintain qualitative characteristics during storage. In a factorial arrangement and a completely randomized design, the first factor was the storage period ...
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Table grape is a non-climacteric fruit with a short shelf-life. The current study aimed at applying specific treatments to prolong its shelf-life and maintain qualitative characteristics during storage. In a factorial arrangement and a completely randomized design, the first factor was the storage period and the second factor was the combination of warm water treatments and gum arabic (GA). The fruits were stored at 5 °C and 80% relative humidity in permanent darkness. On days 0, 20, 40, and 60 of the storage period, seven berries from each replicate were randomly sampled and analyzed for physicochemical and qualitative parameters. The storage time negatively affected the qualities of ‘Bidane-h Ghermez’ table grape fruits. This deterioration in quality was countered by the application of warm water treatments and GA coating, especially by the 45 °C+GA 5% treatment. Compared to the uncoated control group, the application of 45 °C+GA 5% caused a better maintenance of vitamin C (30.43–160.00%), TSS/TA (19.76–21.57%), anthocyanin (37.40–57.75%), antioxidant activity (7.35–36.40%), total phenol (12.01–24.49%), and sensory attributes (66.66–248.50%) in the fruits during storage. Also, this treatment caused lower levels of weight loss (53.27–45.48%), H2O2 (9.90–26.55%), and malondialdehyde (8.84–27.92%). Therefore, the application of warm water treatments and GA coating, particularly at 45 °C+GA 5%, had a remarkable role in extending the shelf-life of table grape fruits. In addition to their effective role in storage, warm water and GA are especially recommended because of their low costs.
Mohammad Javad Nazarideljou; Masoud Azizi
Abstract
Scape bending disorder is the most important factor affecting postharvest loss of gerbera cut flowers. One of the ultimate reasons for gerbera stem bending is lignin, with deformation structural functions and defensive mechanisms. This postharvest experiment was conducted to evaluate the role of phenylalanine ...
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Scape bending disorder is the most important factor affecting postharvest loss of gerbera cut flowers. One of the ultimate reasons for gerbera stem bending is lignin, with deformation structural functions and defensive mechanisms. This postharvest experiment was conducted to evaluate the role of phenylalanine ammonia lyase (PAL) and peroxidase (POD) enzymes activity in stem bending of two gerbera cultivars; (‘Beaudine’ (sensitive)) and (‘Aqua’(resistant)). This experiment was based on a completely randomized design with three replications over eight days. Results showed the significant effects of cultivar on stem bending percentage, total phenol content, PAL and POD enzyme activities and lignin content (P<0.05). The ‘Aqua’ cultivar had the highest phenol and lignin content and the lowest stem bending percentage. The maximum and the minimum PAL and POD enzyme activities were observed in resistant and sensitive cultivars, respectively. Based on the results, induction of PAL and POD enzymes activity, and consequently lignin formation could have direct effects on stem strength and as a result reduce gerbera stem bending disorder.
