•Aloe arborescens gel as edible coating has been used for the first time in fruit.•Aloe vera and Aloe arborescens gels were effective on delaying ethylene climacteric production in both stone ...fruit.•Both coatings delayed ripening index, weight loss and colour evolution during storage at ambient temperature.•Aloe arborescens gel could be alternative to Aloe vera for commercial purposes.
Recently harvested peaches and plums were coated with either Aloe vera or Aloe arborescens gels and allowed to ripen at 20°C for six days. Both coatings significantly delayed ethylene production, the effect being higher in plum which had the highest ethylene production rates. Changes in quality parameters related to peach and plum postharvest ripening, such as colour changes, reduction of acidity and increasing in ripening index (total soluble solids/total acidity ratio), were significantly delayed in coated fruit. In addition, both coatings significantly reduced weight loss, especially the A. arborescens gel. Thus, A. arborescens gel could be even more effective than A. vera gel for use as an edible coating for preserving the quality of climacteric fruit.
: In this work, some organoleptic and nutritive parameters related to fruit quality (color, firmness, total soluble solids, and total acidity), the content of bioactive compounds (total phenolics ...and total carotenoids) as well as the total antioxidant activity (TAA) due to hydrophilic (H‐TAA) and lipophilic (L‐TAA) compounds have been determined in both skin and flesh of 10 flat peach and nectarine genotypes (7 peaches and 3 nectarines). Results showed that genotype plays an important role in determining the organoleptic and nutritive quality, as well as the concentration of bioactive compounds and the related TAA, since these parameters differed largely among cultivars. Overall data suggest that for commercial purposes and consumer's acceptability (based on color, firmness, acidity, and bioactive compounds), the flat nectarine “ASF‐06‐83” and the flat peaches “Sweet Cap” and “ASF‐06‐91” could be considered as the best cultivars. Additionally, it is suggested that the content of bioactive compounds should be included as an important factor in future breeding program to obtain new genotypes with enhanced bioactive compounds.
Practical Application: Genotype of flat peaches and nectarines plays an important role in determining the organoleptic and nutritive quality, as well as the content of bioactive compounds. Given the differences on bioactive compounds concentration and antioxidant activity among peaches and nectarines flat cultivars, these parameters should be included as an important factor in future breeding program to obtain new genotypes with enhanced bioactive compounds.
Ready-to-eat fresh fruit have an increasing presence in international markets due to their convenience and health benefits. However, these products are highly perishable and efficient technologies to ...increase their shelf life are needed. In the present research, different citrus fruit species and cultivars from organic farming were assessed to obtain enzymatically peeled citrus segments. The best results in terms of segment quality were observed for ‘Hernandina’ clementine, which was chosen to make a new ready-to-eat product based on peeled citrus segments that were packaged in glass jars with a light syrup made of citrus juice and organic sugar cane. Different citrus juice mixtures were assayed and the most appreciated syrup, based on the sensory scores given by panellists, was that containing 50–50 (v/v) of ‘Fino’ lemon and ‘Hernandina’ clementine juices. In addition, different pasteurization treatments were assessed for their effects on conserving the safety, nutritional quality and sensory properties of the product during cold storage. The results show that pasteurization treatment at 50 °C for 45 min was sufficient to prevent microbial contamination with mesophilic and psychrophilic aerobic bacteria or yeast and mould and to maintain sensory properties until five weeks of storage at 4 °C. In addition, only a 10% reduction in vitamin C concentrations was observed in fresh-segments or syrup until the end of the storage period, showing that a high bioactive compound content and health benefits were conserved in the new ready-to-eat product after pasteurization and prolonged cold storage.
•‘Black Splendor’ plum behaves as suppressed climacteric plum cultivar.•The highest ethylene and respiration rate inhibition was obtained with preharvest MeJA at 0.5mM.•2.0mM MeJA accelerated ...ethylene production and postharvest ripening based on colour and firmness.•Phenolics and antioxidant activity were higher during storage in 0.5mM MeJA-treated plums.•Antioxidant enzymes along storage showed higher activities in preharvest MeJA treated plums.
‘Black Splendor’ (BS) and ‘Royal Rosa’ (RR) plums were treated preharvest with methyl jasmonate (MeJA) at three concentrations (0.5, 1.0 and 2.0mM) along the on-tree fruit development: 63, 77 and 98 days after full blossom (DAFB). Both control and treated fruit were harvested at the commercial ripening stage and stored in two temperature conditions: 9 days at 20°C or at 2°C+1 day at 20°C for 50 days. Preharvest MeJA at 2.0mM significantly accelerated whereas 0.5mM delayed the postharvest ripening process for both cultivars, since ethylene production, respiration rate and softening were reduced significantly at the two storage conditions for 0.5mM. In these fruit, total phenolics, total antioxidant activity (hydrophilic fraction, HTAA) and the antioxidant enzymes peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were found at higher levels in treated than control plums during postharvest storage, which could account for the delay of the postharvest ripening process and the extension of shelf-life.
Carotenoids are the main colouring substances found in orange-fleshed loquat fruits. The aim of this study was to unravel the carotenoid biosynthetic pathway of loquat fruit (cv. 'Obusa') in peel and ...flesh tissue during distinct on-tree developmental stages through a targeted analytical and molecular approach.
Substantial changes regarding colour parameters, both between peel and flesh and among the different developmental stages, were monitored, concomitant with a significant increment in carotenoid content. Key genes and individual compounds that are implicated in the carotenoid biosynthetic pathway were further dissected with the employment of molecular (RT-qPCR) and advanced analytical techniques (LC-MS). Results revealed significant differences in carotenoid composition between peel and flesh. Thirty-two carotenoids were found in the peel, while only eighteen carotenoids were identified in the flesh. Trans-lutein and trans-β-carotene were the major carotenoids in the peel; the content of the former decreased with the progress of ripening, while the latter registered a 7.2-fold increase. However, carotenoid profiling of loquat flesh indicated trans-β-cryptoxanthin, followed by trans-β-carotene and 5,8-epoxy-β-carotene to be the most predominant carotenoids. High amounts of trans-β-carotene in both tissues were supported by significant induction in a chromoplast-specific lycopene β-cyclase (CYCB) transcript levels. PSY1, ZDS, CYCB and BCH were up-regulated and CRTISO, LCYE, ECH and VDE were down-regulated in most of the developmental stages compared with the immature stage in both peel and flesh tissue. Overall, differential regulation of expression levels with the progress of on-tree fruit development was more evident in the middle and downstream genes of carotenoid biosynthetic pathway.
Carotenoid composition is greatly affected during on-tree loquat development with striking differences between peel and flesh tissue. A link between gene up- or down-regulation during the developmental stages of the loquat fruit, and how their expression affects carotenoid content per tissue (peel or flesh) was established.
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•Biomarkers of off-odors are needed to maintain freshness of leafy vegetables.•Baby spinach stored under low O2 and CO2 generated VOCs responsible for off-odors.•Sensory analyses and ...GC–MS/GC-O were associated to elucidate the complexity of VOCs.•Among 39 odor-active VOCs, only 5 of them were associated with rotten odors.•Sulfur compounds, the most powerful off-odors, can be biomarkers for baby spinach.
Strong off-odor development is still one of the major problems associated with quality loss of baby spinach stored in MA with low O2 and high CO2. Freshness has been generally evaluated by sensory techniques that allow the description of aromatic profiles but it does not identify the responsible compound(s). An approach including sensory analysis and Gas Chromatography-Mass Spectrometry (GC–MS)/Gas Chromatography-Olfactometric (GC-O) techniques were applied to elucidate the complex combination of volatile organic compounds (VOCs) responsible for the off-odor perception of intact baby spinach without generation of new volatiles due to tissue manipulation. After 14days, levels of low O2 and high CO2 (0.3 and 9.3kPa, respectively) were achieved and off-odors development was detected. After GC–MS/GC-O analysis, there were 39 main compounds with olfactory activity, identified as alcohols associated with lipid peroxidation or LOX pathway; sulfur compounds from amino acid degradation; and alkanes from lipid autoxidation processes or carotenoid degradation. Odor-active compounds were grouped into the six odor categories as described by the sensory panel, with rotten and fishy being the strongest odors perceived after storage. The isolated VOCs grouped in the rotten descriptor were the alcohols 1-pentanol, (Z)-3-hexen-1-ol and 1-octen-3-ol, and the sulfur compounds methanethiol and dimethyl disulfide. A compound responsible for fishy notes was dimethyl sulfide but some evidence indicated that amine compounds with low odor thresholds could be also implicated. Since sulfur compounds were perceived by all sniffers and easily detected by mass spectrometry, they may be good candidates as biomarkers of off-odors in baby spinach.
Strong off-odor development is still one of the major problems associated with quality loss of baby spinach stored in MA with low O2and high CO2. Freshness has been generally evaluated by sensory ...techniques that allow the description of aromatic profiles but it does not identify the responsible compound(s). An approach including sensory analysis and Gas Chromatography-Mass Spectrometry (GC-MS)/Gas Chromatography-Olfactometric (GC-O) techniques were applied to elucidate the complex combination of volatile organic compounds (VOCs) responsible for the off-odor perception of intact baby spinach without generation of new volatiles due to tissue manipulation. After 14 days, levels of low O2 and high CO2 (0.3 and 9.3 kPa, respectively) were achieved and off-odors development was detected. After GC-MS/GC-O analysis, there were 39 main compounds with olfactory activity, identified as alcohols associated with lipid peroxidation or LOX pathway; sulfur compounds from amino acid degradation; and alkanes from lipid autoxidation processes or carotenoid degradation. Odor-active compounds were grouped into the six odor categories as described by the sensory panel, with rotten and fishy being the strongest odors perceived after storage. The isolated VOCs grouped in the rotten descriptor were the alcohols 1-pentanol, (Z)-3-hexen-1-ol and 1-octen-3-ol, and the sulfur compounds methanethiol and dimethyl disulfide. A compound responsible for fishy notes was dimethyl sulfide but some evidence indicated that amine compounds with low odor thresholds could be also implicated. Since sulfur compounds were perceived by all sniffers and easily detected by mass spectrometry, they may be good candidates as biomarkers of off-odors in baby spinach.
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