Ready-to-eat products are damaged by various factors, including exposure to O2 and CO2, extreme temperatures, and rapid decay, due to trauma during processing. The use of natural antimicrobial agents ...and antioxidants might extend the shelf-life of the fruits. The aim of this work is to investigate the effects of four different antibrowning and gelling agents added into the Aloe vera gel-based edible coatings and applied to fresh-cut papaya. EC1 treatment consists of Aloe vera gel (30% v/v), EC2 contains CaCl2 (5% v/v), EC3 contains K carrageenan (0.5% v/v), and EC4 contains sodium alginate (1.5% v/v) and K carrageenan (0.5% v/v). The fruits treated with EC2 showed the best results while maintaining high values in terms of firmness (that differ from the control of 42.5%), soluble solid content (that differ from the control of 14.6%), and titratable acidity (that differ from the control of 49%). Hence, the addition of CaCl2 also reduces the ripening rate and loss of color without altering the product’s sensory qualities. EC3 and EC4 treatments have provided an oxygen barrier and reduced respiratory rate, increasing the firmness retention and keeping a high C∗ value thanks to K carrageenan and sodium alginate.
Fig fruits are usually highly sensitive to some physiopathological disorders during post-harvest life, such as softening and skin cracking. Indeed, the use of edible coating (EC) has been evaluated ...in several fruit crops to reduce fruit post-harvest transpiration and to maintain fruit visual quality. The aim of this study was to determine the post-harvest metabolic response of breba figs treated with mucilage extract from
cladodes, using an untargeted metabolomic approach. Coated and non-coated (control) fruit were sealed in plastic bags, and stored at 4°C for 7 days. The effect of the ECs on their quality fruit during cold storage and qualitative attributes were evaluated by analyzing the fruit primary metabolism and other qualitative parameters such as total soluble solids (TSS) content, titratable acidity (TA), fresh weight loss and firmness. Results underlined that EC was effective in maintaining fruit fresh weight, and fruit firmness. Stepwise discriminant analysis was able to discriminate fruit conditions. Alanine, xylulose, aspartic acid, glutamic, acid and 2,5-dihydroxypyrazine showed a significant role on discriminating edible coated fruit from untreated ones. Principal component analysis (PCA) was able to highlight clear differences in the overall metabolism changes between untreated and treated fruit. The application of EC significantly mitigated the decrease of most of the aminoacid content during cold storage. EC treatment caused the changes of several organic acids in comparison to untreated control, increasing the amount of carbohydrates and other key metabolites, such as beta-sitosterol, glycerol, and uracil. These results clearly showed the drastic effects of EC on fig metabolism during post-harvest and shed light on the beneficial mechanisms of this treatment.
Powdery mildew (PM) is a major fungal disease of thousands of plant species, including many cultivated Rosaceae. PM pathogenesis is associated with up-regulation of MLO genes during early stages of ...infection, causing down-regulation of plant defense pathways. Specific members of the MLO gene family act as PM-susceptibility genes, as their loss-of-function mutations grant durable and broad-spectrum resistance.
We carried out a genome-wide characterization of the MLO gene family in apple, peach and strawberry, and we isolated apricot MLO homologs through a PCR-approach. Evolutionary relationships between MLO homologs were studied and syntenic blocks constructed. Homologs that are candidates for being PM susceptibility genes were inferred by phylogenetic relationships with functionally characterized MLO genes and, in apple, by monitoring their expression following inoculation with the PM causal pathogen Podosphaera leucotricha.
Genomic tools available for Rosaceae were exploited in order to characterize the MLO gene family. Candidate MLO susceptibility genes were identified. In follow-up studies it can be investigated whether silencing or a loss-of-function mutations in one or more of these candidate genes leads to PM resistance.
Fresh-cut peach is very perishable, being discoloration or browning the main factors affecting loss quality and consumer acceptability. The aim of the study was to investigate the effect of chemical ...treatments on sensory peaches profile 'Pesca di Bivona' and 'Pesca di Leonforte' landraces, treated with 2 % ascorbic acid and 1 % calcium lactate (AA), or 1 % ascorbic acid and 1 % calcium lactate and 0.5 % citric acid (SOL) during 12 days of storage. 150 g of peach fruit slices were placed in rigid bi-oriented polystyrene bags and stored for 3, 5, 7 and 12 days at 5 ± 1 °C in passive atmosphere condition. For each sampling day color, sensorial analysis, respiration rate, firmness, total soluble solids, titratable acidity, ascorbic acid and total phenols were measured. Our results showed that the use of ascorbic acid in combination with calcium lactate gave the best results in terms of overall liking in both 'Pesca di Bivona' and 'Pesca di Leonforte' genotypic groups after 7 days of storage. However, 'Pesca di Bivona' and 'Pesca di Leonforte' landraces had a different behavior to antioxidant treatments with AA in terms of browning, acidity, vitamin C and total phenolic content maintaining a high smell, flavor and juice attributes.
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•Ascorbic acid with Calcium lactate maintained the highest postharvest quality for seven days.•Fresh-cut peaches treated with (AA) and (SOL) alleviated surface browning.•AA treatment gave the best results in terms of overall liking after 7 d of storage.•Fresh-cut peaches treated with (AA) and (SOL) maintained most of quality attributes.•'Pesca di Bivona' and Leonforte' landraces maintained a high smell, flavor and juice.
Fig is a widespread crop in southern Italy, highly valued for its sweet flavor. However, its consumption as a fresh product is limited to three to four days after harvest because of its high ...susceptibility to quality loss and microbial contamination. The combined use of low temperature and a modified atmosphere is the traditional preservation method. However, several studies have shown that the use of Aloe arborescens or vera and O. ficus-indica (OFI) mucilage as an edible coating could reduce the microbial load and water loss, respectively. Therefore, our study aimed to evaluate the synergistic effects of Aloe gel (AG) and O. ficus-indica mucilage (OM) on the quality and safety of two fig cultivars, ‘San Giovanni’ and ‘Melanzana’, during cold storage at 4 °C. The main results showed the effectiveness of edible coatings on both fig cultivars. An AG coating significantly reduced the microbial load, while the OM treatment showed the ability to preserve firmness and reduce weight loss. In addition, the combined OM + AG treatment showed the same effects as the individual coating formulations, also improving visual appearance. Thus, the use of the synergetic coating formulation could be a natural way to reduce the microbial load, extending fresh fig fruit’s shelf life.
Background
Persimmon fruits are cherished for their unique flavor and high nutrient content. In the present study, the effects of
Aloe vera
-based edible coatings (EC) added with 1% ascorbic acid, 1% ...citric acid and 5% calcium chloride in modified atmosphere packaging (MAP) and their impact on shelf-life quality of fresh-cut persimmon fruit, were investigated. The experimental design consisted of four treatments 1)
Aloe vera
edible coating + modified atmosphere packaging (EC + MAP), 2) untreated fruit packaged with MAP (CTR + MAP); 3)
Aloe vera
-based edible coating in passive atmosphere (EC PASSIVE); 4) untreated fruit in passive atmosphere (CTR PASSIVE). Persimmon fruit were stored at 5 °C for 3, 6 and 9 days. At each storage time, firmness, weight loss, sugar content, organic acids, polyphenol oxidase (PPO), browning index respiration rate, sensory and microbiological analysis, were investigated.
Results
Our results were confirmed also by the sensory analysis in which both EC-treated fruit scored the highest values for positive descriptors.EC + MAP treatment showed the most effective result in maintaining total carotenoids, ascorbic acid, glucose and CO
2
inside packaging reducing the PPO activity and the flesh browning of persimmon slices. EC + MAP treatment controlled the growth of total mesophilic microorganisms, pseudomonads,
Enterobacteriaceae
, yeasts and molds
.
Conclusions
The obtained results confirmed the importance of coating composition in controlling post-harvest decay and maintaining fruit quality.
Alternate bearing is a typical behavior of various fruit tree crops and is common among olive cultivars (Olea europæa L. var. sativa Hoffm. e Lk.). Since this phenomenon affects yield and ...consequently oil production, it is a concern for olive oil industry in order to offer a constant olive oil amount each year. A 4-year field experiment was conducted on cv Chemlali olive trees in ‘on’ and ‘off’ years in order to study, under arid conditions, both annual macro-element balance and net photosynthetic activity. Shoots growth was much higher in the ‘off’ year with respect to the ‘on’ one (+11.70 cm vs. +2.60). Net photosynthesis rate was much higher in the ‘off’ year with respect to the ‘on’ year and the highest values were observed at spring, when there is an intense vegetative growth. Differences for the mineral elements were observed between the ‘on’ and ‘off’ years. Nitrogen accumulated in leaves mainly in spring in the ‘off’ year, whereas high N values were detected also at the end of summer in the ‘on’ year. Consequently, N fertilization can be accomplished in February–March and possibly after harvest (November–December) to be used at budburst in the successive season. A difference was found between leaf P concentrations in ‘on’ or ‘off’ years from flowering to fruit-set, with the lowest values in the ‘on’ year, in particular in June–July. A supply of P at autumn–winter and partially in spring–summer in particular in an ‘on’ year would be appropriate. K accumulated in leaves in ‘on’ year from spring to summer, thus a supply of K in January–February, before new vegetation, for trees either in ‘on’ or ‘off’ year can be necessary for supporting and implementing the root system activity and the successive shoot growth (‘off’ year) and fruit development (‘on’ year). These results should be useful to partially reduce, through an appropriate fertilization schedule, the alternate bearing in olive tree.
•Main factors affecting quality in wine and table grapes are reviewed.•Genetic related features of main compositional traits are presented.•Environmental factors as light, temperature and water ...supply are addressed.•Yield/quality relationship and main summer pruning practices are discussed.•Outlooks for improving quality are given.
Over decades, the concept of grape quality has evolved emphasizing its multidisciplinary nature and that the same “desired quality” might correspond to even strikingly different compositional patterns. The review takes a long journey throughout the multiple factors impinging on grape quality, not excluding also sections devoted to table grapes. It starts with a through survey on the genetic factors influencing grape quality focusing on diversity in different compositional traits (sugar, organic acid, pH, phenolics and aromas) relating to cultivars and clones. Then, most recent knowledge about the effects of soil characteristics, nutrients, light, temperature and water availability, as standalone factors or in interaction, on grape quality are summarized. The more applied section of the review introduces the very much debated yield-quality relationship that, over years, is being interpreted with more flexibility and with greater consensus for an “optimal yield range” that within a given context can anyway reach the desired quality. The impact of the main summer pruning operations (leaf removal, shoot and cluster thinning, shoot trimming) is reviewed and special care taken to highlight most recent contributions with adjusted summer pruning developed to either adapt to climate change issues or to induce specific composition patterns. Review ends with a quick survey on methods nowadays available for fast, non-destructive grape composition assessment.
Manna is the sap extracted in summer from the phloem of the stem and the old branches of Fraxinus sp. trees. Its composition is characterized by a high content of D-mannitol, gallic acid, tyrosol and ...a great antioxidant activity. The aim of the present work was to compare the effect of a solution enriched with manna or calcium ascorbate, the latter widely used by researchers as an antioxidant agent on the control of browning of apple slices. After harvest, apple fruit were cut, treated with manna (MN), calcium ascorbate (CA) or with distilled water as a control (CTR), and packed in polylactic acid (PLA) packaging. Physical, chemical and sensory analyses were performed after 3, 5, 7 and 10 days of storage at 5±0.5 °C. After one week of storage, manna and calcium ascorbate-based treatment significantly inhibited apple fruit slices browning of cut surface, to the same extent, while no significant differences occurred in terms of weight loss, DPPH, total carotenoids and flavor score. On the whole, manna may inhibit apple slices water loss without affecting fruit flavour and providing the maintenance of their shelf-life. It seems that manna and calcium ascorbate mechanism and effect on browning inhibition are very similar and account for maintaining stored apple slices shelf-life up to 7 days. Therefore, our work lays the foundations for the use of manna as a natural antioxidant compound capable of reducing fresh-cut enzymatic browning
•Manna composition is characterized by gallic acid, tyrosol and antioxidant activity.•Manna treatment reduced softening and weight loss.•Manna and calcium ascorbate effect on browning inhibition are very similar.•Manna treatment application didn’t affect apple slices flavor.•The increases of phenols can promote browning on the cut surface of apple.
•Big Bang fruit harvested at 50N, could be stored at 1±0.5°C for no more than 10d.•Fresh-cut derived from fruit stored for 10d had always the same fresh weight loss.•The longer the fruit were stored ...before processing, the lower the L* of fresh-cut.
Nectarine can be minimally processed to successfully produce ready-to-eat fresh-cuts fruit. The aim of this work was to study the combined effect of the ripening stage of cold stored fruit before processing and the length of the storage period of fresh-cut slices after minimal processing, on the behaviour of minimally processed “Big Bang” nectarines during shelf life. ‘Big Bang’nectarine slices obtained from fruit stored at 1±0.5°C (RH=90%) for 1d, 10d and 15d were stored for 0, 3, 5, 7, 12d. at 5°C. At the end of each storage period, visual quality, color (L*, a* and b*), phenols and carothenoids content, TSS, TA were measured together with in-package CO2 and O2. Despite the more advanced ripening stage and the increase of polyphenol oxidase activity and ethylene production, nectarine fruit stored for 10days were successfully processed to get fresh-cuts still marketable until 7d after being cutting. Indeed, no difference occurred between fruit stored for 1d before cutting and those stored for 10d, in terms of firmness, weight loss and marketability of fresh-cut slices. The carotenoid content went descending dramatically in all samples of ‘Big Bang’ slices while in-package CO2 partial pressures were highest at 5, 7, 12d of storage in fresh-cut to more from fruit stored for 1d.
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