Quality Traits and Nutritional Components of Cherry Tomato in Relation to the Harvesting Period, Storage Duration and Fruit Position in the Truss.

It is well known that the harvesting period and the storage duration have a significant effect on the quality characteristics of cherry tomato fruits. On the other hand, the effect of the fruit position in the truss has not been studied, as well as the relative contribution of each one of these factors on fruit quality. For this purpose, cherry tomato (Genio F1) whole trusses were harvested at the fruit red ripe stage during three periods. At each harvesting period, the first four (at the base of the truss) and the last four (at the top) fruits from each truss that was previously trimmed to 10 fruits, were stored at 12 °C for 0, 4 and 10 days. At the end of each storage duration, the external color, firmness, antioxidant capacity, pH and titratable acidity, as well as dry matter, soluble solid, total soluble phenol, lycopene, total carotenoid and ß-carotene content, were determined. Analysis of variance (ANOVA) indicated that the harvesting period had the most significant effect on skin color parameters L * and C * and ß-carotene, as well as on antioxidant capacity, total soluble phenols, dry matter and total soluble solids, while it also had an appreciable effect on titratable acidity. The storage duration had a dominant effect on firmness, total carotenoids and lycopene, while it had an appreciable effect on skin color parameter L * as well. On the other hand, the fruit position in the truss exerted an exclusive effect on ho and a */b * ratio skin color parameters and pH and an appreciable effect on titratable acidity.

Nutritional composition changes in bell pepper as affected by the ripening stage of fruits at harvest or postharvest storage and assessed non-destructively.

BACKGROUND: Nutritional quality in bell pepper is related to the ripening stage of the fruit at harvest and postharvest storage. Its determination requires time-consuming, tissue-destructive, analytical laboratory techniques. The objective of this study was to investigate the effect of ripening stage and of postharvest storage period on fruit nutritional quality, and whether it is feasible to develop reliable models for assessing the nutritional components in peppers using non-destructive methods. The dry matter, soluble solids, ascorbic acid, phenolics, chlorophylls, carotenoids and the total antioxidant capacity were determined in bell pepper fruits at six ripening stages, from green to full red, during storage at 10 °C for 8 days. Color, chlorophyll fluorescence, visible/near infrared (Vis/NIR) spectroscopy, red-green-blue (R-G-B) and red-green-near infrared (R-G-NIR) digital imaging were tested for assessing the nutritional quality of peppers. RESULTS: The nutritional composition was mainly affected by the ripening stage of bell pepper fruits at harvest and only to a small degree by the storage period. Indeed, the more advanced ripening stage of fruit at harvest resulted in superior nutritional quality. Most of the non-destructive techniques reliably predicted the internal quality of the fruit. The genetic algorithm (GA), the variable importance in projection (VIP) scores, and the variable inflation factor (VIF) tests identified nine distinct regions and four specific wavelengths on the whole visible/NIR electromagnetic spectrum that exhibited the most significant effect in the assessment of the nutritional components. CONCLUSION: It is possible to predict individual nutritional components in bell pepper fruit reliably and non-destructively, and irrespective of the ripening stage of fruits at harvest. © 2021 Society of Chemical Industry.

Improvement of sea fennel (Crithmum maritimum L.) nutritional value through iodine biofortification in a hydroponic floating system.

Sea fennel is an herbaceous aromatic and edible halophyte, naturally occurring in coastal areas of the Mediterranean basin. Besides its scientific interest as a salt-tolerant species it exhibits considerable nutritional value and economical potential. As sea fennel is distributed in maritime areas, where natural iodine is available in high concentrations, the aim of this study was to evaluate whether sea fennel has the potential to accumulate elevated iodine concentrations under cultivation. A biofortification experiment in a hydroponic system applying two forms of iodine, KI and KIO3 in different concentrations was set up and monitored using sophisticated targeted elementary and metabolite analysis. The biofortification potential and possible effects on nutritional value were investigated. This study revealed that both iodine forms increased the iodine content of sea fennel tissues. Nutritional and health promoting components, biomass production but also antioxidant potential were stable or even improved under the iodine treatments.

Biochemical and histological contributions to textural changes in watermelon fruit modulated by grafting.

Increased watermelon fruit flesh firmness is systematically incurred with grafting on Cucurbita hybrid rootstocks (heterografting). Possible differences in mesocarp cell wall constitution and histology between heterografted, homeografted (self-grafted) and non-grafted watermelon were examined, as well as their contributions to fruit texture. Firmness correlated positively (r=0.78, p<0.001) with cell density (cellsmm-2) which was higher in heterografts (5.83) than homeografts (4.64) and non-grafted controls (4.69). Mean cell size was smallest in heterografts and correlated negatively (r=-0.75, p<0.001) with firmness. Cell wall material, particularly the water-insoluble pectin fractions associated with firmness, were highest in heterografts. No associations with firmness were found for cell wall neutral sugars and membrane permeability. Higher parenchymatic cell density with higher content of alcohol insoluble residue and more abundant water-insoluble pectin fractions underscore enhanced firmness in heterografts. Possible implication of osmolytes in rootstock-mediated cell pressure regulation warrants further investigation.

Configuration of watermelon fruit quality in response to rootstock-mediated harvest maturity and postharvest storage.

BACKGROUND: The configuration of watermelon fruit quality was analysed in a multi-factorial approach accounting for the effects of grafting, harvest maturity and postharvest storage. Diploid, seeded, hybrid cv. Pegasus, cultivated as scion on interspecific hybrid squash rootstock TZ148 and as non-grafted control, was stored at 25 °C following sequential harvests from the onset of ripening to over-maturity. RESULTS: Delayed rootstock-mediated climax in pulp lycopene and chroma was observed, while both were heightened by postharvest storage when harvest preceded full maturity. Pulp firmness was increased by 46.5% on TZ148, while postharvest decrease in firmness was non-significant. Non-grafted fruits attained their peak in pulp carbohydrate content earlier during ripening. Monosaccharide content declined and sucrose content increased both preharvest and postharvest; overall sugar content declined by 4.3% during storage. Pulp acidity decreased steadily with ripening but was moderately increased by grafting. Citrulline content increased by 12.5% on TZ148; moreover, it climaxed with ripening and declined with storage only in grafted fruit. CONCLUSION: Grafting enhances pulp texture and bioactive composition. Potential suppression of sugar content as a result of grafting is minimized at full commercial maturity. Brief postharvest ambient storage enhances pulp lycopene and chroma, especially in early-picked fruit, notwithstanding the depletion of monosaccharides and citrulline and a limited deterioration of texture. © 2015 Society of Chemical Industry.

Composting Phragmites australis Cav. plant material and compost effects on soil and tomato (Lycopersicon esculentum Mill.) growth.

Composting organic residues is a friendly to the environment alternative to producing fertilizer. This research was carried out to study the process of composting Phragmites australis Cav. plant material alone or with animal manure on a pilot-scale, to evaluate firstly the quality of the composts produced and secondly, using a pot experiment, the effects of their application on soil physicochemical characteristics and tomato plants development. For the compost production a randomized complete block design was used with five treatments (five compost types) and four replications. For the pot experiment, a completely randomized design was used with 17 treatments (plain soil, soil with synthetic fertilizer and the application of five compost types, at three rates each) and five replications. Compost N increased with composting time, while C/N ratio decreased significantly and by the end it ranged from 43.3 for CM to 22.6 for CY. Compost pH became almost neutral, ranging from 6.73 for CY to 7.21 for CM3Y3AM4 by the end. Compost combinations CY7AM3 and CM7AM3 had a more positive influence on the soil physicochemical characteristics than the others. Soil N, P, Ca and Mg concentrations and the reduction of clay dispersion were the highest when CM7AM3 compost was added. The macro-aggregate stability was the highest for CY7AM3, which also sustained plant growth. The latter compost combination improved most of the soil physicochemical characteristics and plant growth especially, when the application rate was 4% (w/w), which equals to 156 Mg ha(-1).

Effects of genetic, pre- and post-harvest factors on phenolic content and antioxidant capacity of white asparagus spears.

The effects of genetic, pre-harvest (season of harvest, spear diameter, spear portion and spear tip color) and post-harvest factors (storage and domestic preparation practices, e.g., peeling and cooking) on total phenolic, flavonoid and ascorbic acid content of white asparagus spears and their correlation with antioxidant capacity (DPPH and FRAP) were studied. Results showed that genetic material was important for the total phenolic content but not season of harvest, spear diameter or storage. Violet spear tips and apical spear portions showed the largest amount of total phenolics. Peeling did not affect total phenolics in fresh asparagus, whereas it reduced their content in stored asparagus, while cooking resulted in an increase in both fresh and stored asparagus. However, the soluble extract of total phenolics and flavonoids were minor and the missing significance of phenolics and flavonoids in antioxidant capacity of white asparagus spears depends on these small amounts.