Fruit Pulp Firmness Research Articles

Effect of postharvest spermidine treatments on quality and biochemical properties of nectarine fruits

In this study, the effect of spermidine (SP) treatments at different doses after harvest on the changes in the pomological and biochemical contents of nectarine fruits was determined. The fruits were placed in cold storage (4 ± 0.5 °C and 90 ± 5% RH) for 30 days. Specific organic acids and phenolic compounds from biochemical compounds were analyzed by HPLC device. Weight loss and decay values, which are quality criteria of nectarine fruits, increased during storage compared to the harvest period. In this study, 1.0 mM SP application was found to be more successful in the preservation of visual quality (fruit pulp firmness and weight loss) properties during storage. At the end of the storage period (30th day), weight loss was determined as 3.27% in the control group and 1.84% in the 1.5 mM SP treatment. Fruit flesh firmness value, which is one of the important quality parameters affecting the storage life of fruits, was determined as 30.97 N in the control group and 37.06 N in 1.5 mM SP doze (30th day). Contrary to the acidity values, the total soluble solids content (TSS) and fruit juice pH values increased during storage. In this research, when the organic acid and phenolic compound contents are examined; it was determined that the dominant organic acid and phenolic compound in nectarine fruits were malic acid and chlorogenic acid, respectively. The malic acid ratio was found to be 4.89 g/kg in the control group and 6.66 g/kg in 1.5 mM SP treatment at the end of the 30-day storage period. Chlorogenic acid content was recorded as 6.86 mg/100g in the control group and 8.82 mg/100g in 1.5 mM SP application at the end of the storage period (30th day). In this study, it was determined that a 1.5 mM SP dose after harvest was effective on the biochemical contents of nectarine fruits and protected the fruits more during storage.

Postharvest physiology and biochemistry of Valencia orange after coatings with chitosan nanoparticles as edible for green mold protection under room storage conditions.

Because of their unique features, nanomaterials have been proposed and have gained acceptance in postharvest applications in fruit. Increasing the storage life and improving the quality of Valencia oranges was investigated using nano-chitosan. A chitosan nanoparticle was prepared by using high-energy ball milling. Chitosan nanoparticles were characterized by Dynamic light scattering, FTIR spectroscopy and Surface morphology by transmission electron microscopy. Fully mature Valencia oranges were harvested and then coated with one of these concentrations (0.2, 0.4, and 0.8% nano-chitosan) and control. The fruits were stored under room storage conditions for 75 days. The quality parameters (fruit weight losses, fruit decay percentage, fruit firmness, total acidity, total soluble solids percentage and T.S.S./acid ratio, ascorbic acid content) were taken in biweekly intervals after 0, 15, 30, 45, 60, and 75 days. Beside the in vitro testing of antifungal activity of chitosan nanoparticles. According to the findings of the two succeeding seasons, the nano-chitosan 0.8% treatment showed the best effects and had the lowest rate of fruit weight loss, fruit deterioration, and T.S.S./acid ratio in comparison to the other treatments in both seasons. Furthermore, the 0.8% nano-chitosan reveled the highest levels of fruit hardness and fruit pulp firmness. Fruit weight loss, fruit deterioration, TSS, and TSS/acid ratio, as well as other metrics, were steadily elevated prior to the storage time. The best results were obtained when Valencia oranges fruits were treated with 0.8% nano-chitosan for 75 days at room temperature.

Relationship between biospeckle laser technique and firmness of Acrocomia aculeata fruits

ABSTRACT Knowing the maturation of the Acrocomia aculeata (macaw palm) fruit is decisive for harvest to be performed when the fruit has a higher content and quality of oil. There are different approaches to monitor maturation and they can be classified as destructive and non-destructive. Variables obtained by optical instruments have been used to determine maturation stage. The present study evaluated the relationship between the biological activity measured by the optical technique of biospeckle laser and firmness, measured in the Acrocomia aculeata fruit pulp between the 41st and 61st week after flowering. The biological activity was quantified by biospeckle images, while the fruit pulp firmness was determined by digital penetrometer. Correlations between variables were evaluated during maturation and in the senescence of fruits. According to the results, significant correlation between biological activity and firmness was found for both evaluated conditions, demonstrating that biospeckle laser can be an effective non-invasive indicator of Acrocomia aculeate fruit maturation assisting in the determination of the moment of harvest.

Multivariate analysis applied to the study of the relationship between soil and plant properties in a peach orchard

In the State of Rio Grande do Sul, the municipality of Pelotas is responsible for 90 % of peach production due to its suitable climate and soil conditions. However, there is the need for new studies that aim at improved fruit quality and increased yield. The aim of this study was to evaluate the relationship that exists between soil physical properties and properties in the peach plant in the years 2010 and 2011 by the technique of multivariate canonical correlation. The experiment was conducted in a peach orchard located in the municipality of Morro Redondo, RS, Brazil, where an experimental grid of 101 plants was established. In a trench dug beside each one of the 101 plants, soil samples were collected to determine silt, clay, and sand contents, soil density, total porosity, macroporosity, microporosity, and volumetric water content in the 0.00-0.10 and 0.10-0.20 m layers, as well as the depth of the A horizon. In each plant and in each year, the following properties were assessed: trunk diameter, fruit size and number of fruits per plant, average weight of the fruit per plant, fruit pulp firmness, Brix content, and yield from the orchard. Exploratory analysis of the data was undertaken by descriptive statistics, and the relationships between the physical properties of the soil and of the plant were assessed by canonical correlation analysis. The results showed that the clay and microporosity variables were those that exhibited the highest coefficients of canonical cross-loading with the plant properties in the soil layers assessed, and that the variable of mean weight of the fruit per plant was that which had the highest coefficients of canonical loading within the plant group for the two years assessed.