Burhan Ozturk

Physico-mechanical Properties and Colour Characteristics of Apple as Affected by Methyl Jasmonate Treatments

Physical (geometric, volumetric and colour) and mechanical properties of apple (cv. Fuji) as affected by Methyl Jasmonate treatments were analyzed. Geometric mean diameter, fruit mass, sphericity and surface area ranged from 71.36 to 69.97 mm, 196.53 to 194.83 g, 1.126 to 1.129, and 161.32 to 158.11 cm2 with MeJA doses, respectively. The bulk and fruit densities varied from 383.65 to 364.22 kg/m3 and from 967.96 to 954.63 kg/m3, with MeJA treatments. L*, a*, b* value of skin apple changed from 50.76 to 46.89, from 28.06 to 30.35, and from 24.58 to 22.43, respectively with MeJA doses. The skin and flesh firmnesses varied from 101.49 to 112.60 N and 74.18 to 72.71 N, respectively. The sphericity and projected area increased with MeJA doses used. As the MeJA doses increased, the bulk and fruit densities decreased, whereas volume increased. L*, b* and hue angle characteristics of skin apple were found to decrease, whereas a* was found to increase with MeJA doses. The fruit-removal-force was decreased linearly with increasing MeJA doses. The rubber surface offered the maximum friction followed by plywood and galvanized metal for MeJA doses.

Changes of Bioactive Compounds and Ethylene Production of Japanese Plums Treated with Pre-Harvest Aminoethoxyvinylglycine

The effects of pre-harvest aminoethoxyvinylglycine treatments on bioactive compounds, fruit ripening, and quality of plum fruits (Prunus salicina Lindell cvs. “Black Beauty,” “Black Amber,” and “Friar”) were investigated in this research. Whole trees were sprayed once with an aqueous solution containing aminoethoxyvinylglycine (0, 100, and 200 mg L–1) two weeks before the anticipated commercial harvest for each cultivar separately. In all plum cultivars, the results showed that aminoethoxyvinylglycine treatments were effective in reducing ethylene production and respiration rate. The red color development was delayed by aminoethoxyvinylglycine treatments during the ripening. The fruit mass and geometric mean diameter significantly decreased, while loss of flesh firmness was decelerated with aminoethoxyvinylglycine concentrations. Aminoethoxyvinylglycine treatments decelerated loss of flesh firmness. Soluble solid content was reduced, whereas titratable acidity and ripening index increased with aminoethoxyvinylglycine treatments. Aminoethoxyvinylglycine-treated fruits exhibited lower levels of total phenolics, total antioxidant activity, and individual phenolics. This study revealed that pre-harvest aminoethoxyvinylglycine treatments were more effective in delaying plum fruit softening. The main advantage is to maintain the firmness of late-harvested fruit by retaining bioactive compounds of plum fruit.

The effects of pre-harvest application of aminoethoxyvinylglycine on the bioactive compounds and fruit quality of 'Fortune' plum variety during cold storage.

The effects of pre-harvest aminoethoxyvinylglycine treatments on fruit quality parameters and bioactive compounds of ‘Fortune’ plum during cold storage were investigated. Two different aminoethoxyvinylglycine doses were applied to plum trees two weeks prior to the estimated harvest date, and harvested fruit samples were kept in cold storage at 0 oC temperature and with 90 ± 5% relative humidity for 4 weeks. Lightness (L*) and hue angle values decreased in all treatments during cold storage. Weight loss (%) was significantly decreased (p < 0.05) with 100 mg/L aminoethoxyvinylglycine treatment at the end of the storage. Fruit firmness at the end of the storage was significantly increased with aminoethoxyvinylglycine treatments. Total phenolics and total antioxidant activity were increased with aminoethoxyvinylglycine treatments till the 21st day of storage and decreased by the 28th day. Total phenolics and total antioxidant activity were significantly decreased (p < 0.05) with the 200 mg/L aminoethoxyvinylglycine treatment at the end of storage. Rutin was significantly decreased with 100 mg/L aminoethoxyvinylglycine treatment at the end of cold storage.

The effect of NAA (1-naphthalene acetic acid) and AVG (aminoethoxyvinylglycine) on physical, chemical, colour and mechanical properties of Braeburn apple

Abstract Recently, plant growth regulators have been used for multiple purposes in tree fruits. NAA (1-naphthalene acetic acid) and AVG (aminoethoxyvinylglycine) have been widely used in apple fruit. NAA and AVG have been used to control preharvest fruit drop and improve the quality of fruit. In this study, the effects NAA (20 mgL–1), AVG (500 mgL–1) and control (non treatment) treatments on physical, chemical, colour characteristics and mechanical properties of apple (cv. Braeburn) were investigated. The higher length, width, thickness, geometric mean diameter, fruit mass, surface area, projected area, volume, fruit and bulk densities were obtained in AVG treatment. Total acidity, total soluble solid content and starch starch index were higher in control as compared to NAA and AVG treatments. Total phenolic content of the flesh apple was higher than the other treatments. While total antioxidant activities of skin and flesh fruit were higher in AVG according to FRAP method, total monomeric anthocyanin was lower in AVG as compared to the other treatments. AVG treatment generally had positive impacts on fruit removal force, skin and flesh firmnesses because retarding the fruit ripening.

Effects of Pre-Harvest Methyl Jasmonate Treatments on Bioactive Compounds and Peel Color Development of “Fuji” Apples

The present study was conducted to investigate the effects of pre-harvest methyl jasmonate treatments on peel color formation, total anthocyanin, total phenolics, total antioxidant capacity, and other selected fruit quality parameters of “Fuji” apples. Results revealed significant decreases in color parameters (L*, chroma, and hue values) with methyl jasmonate treatments. Total anthocyanin, total phenolics, and total antioxidant capacity of methyl jasmonate-treated fruits were significantly higher than control fruits. Methyl jasmonate concentrations increase linearly with increase in total anthocyanin, total phenolics, and total antioxidant capacity with high correlations. Ethylene synthesis-promoting impact of methyl jasmonate increased with increasing implementation doses. Methyl jasmonate treatments also increased fruit flesh firmness. While 1120 and 2240 mg/L methyl jasmonate treatments did not cause any significant changes in the starch degradation, 4480 mg/L methyl jasmonate treatment delayed the starch degradation. All methyl jasmonate treatments did not cause any or much significant changes in fruit mass, geometric mean diameter and soluble solids content of the fruits but yielded significant increase in titratable acidity values.

Effect of Aminoethoxyvinylglycine and Methyl Jasmonate on Individual Phenolics and Post-harvest Fruit Quality of Three Different Japanese Plums (Prunus salicina Lindell)

Abstract In this research, effects of aminoethoxyvinylglycine (AVG) and methyl jasmonate (MeJA) applied 2 weeks ahead of estimated harvest date on fruit color, firmness and individual phenolic compounds of three plum varieties wereinvestigated during the cold storage. Fruits of “BlackAmber”, “Black Beauty” and “Fortune” were kept at 0 ± 0.5°C temperature and 90 ± 5% relative humidity for 4 weeks. During the storage, decreases in L*, chroma and hue angle values were observed. AVG treatments differed significantly (p < 0.05) by control and MeJA treatment. In all plum varieties, AVG treatment resulted in significant increases in flesh firmness at the end of storage. MeJA increased significantly the firmness of “Black Beauty” and “Fortune” fruit at the end of storage. Chlorogenic acid was detected as major phenolic compound in plum varieties. AVG treatment to “Black Amber” fruit increased the contents of chlorogenic and p-coumaric acid during storage, whereas it reduced chlorogenic and p-coumaric acid content in “Fortune” fruit. MeJA treatment led to not only increase the contents of rutin, ferulic acid and naringenin in the fruits of “Black Beauty” and “Fortune” varieties during the storage but also significantly increase the kaempferol content in “Black Amber” and “Black Beauty” fruits. While AVG treatment compared to control significantly decreased the contents of chlorogenic acid, quercetin and naringenin in “Black Amber” fruits at the end of cold storage, it increased content of p-coumaric acid. At the end of storage, AVG and MeJA treatments reduced significantly the content of ferulic acid in “Black Beauty” fruits. In addition, MeJA treatment significantly increased chlorogenic acid, ferulic acid and kaempferol contents in “Fortune” fruits.