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Apricot (Prunus armeniaca L.) is globally the third most cultivated stone fruit, prized for its flavourful and nutritious fruit. However, its climacteric nature impacts postharvest behaviour, shortening shelf-life. While the role and interaction of key genes and proteins involved in the ripening process of this species have been extensively studied over the years, research on ethylene suppressors like 1-methylcyclopropene (1-MCP) and cold storage is still limited. Fruit samples from 10 genotypes were collected at commercial maturity from the CEBAS-CSIC research centre and divided into three groups: control (T0), one application of 1-MCP at harvest (T1), and two applications of 1-MCP at harvest and after seven days of cold storage (T2). The study aimed to assess the effects of these treatments on fruit quality traits, such as skin color, soluble solids, acidity, firmness, and ethylene production, after various cold storage periods (10, 20, and 30 days) at 1°C, followed by 48 hours at 20°C. Cold storage combined with 1-MCP effectively reduced fruit softening and ethylene production, with varying impacts on fruit quality traits depending on the genotype. '906–12' and 'Goldrich' were identified as the most contrasting genotypes in terms of ethylene production and fruit softening. Additionally, the application of 1-MCP reduced the expression of genes responsible for fruit softening, coloration and some organoleptic characteristics while enhancing those promoting antioxidant activity during ripening. This study sheds light on the molecular processes involved in apricot fruit ripening and highlights the potential of this approach for enhancing postharvest preservation. • Deeper exploration of fruit quality, postharvest traits, and key ripening genes. • 1-MCP significantly reduced ethylene production, maintaining fruit firmness. • Genotype-dependent response to 1-MCP treatment in delaying ripening. • Suppression of PME, PG, and ACS genes in fruit softening by 1-MCP. • Potential impact on aroma and antioxidant activity due to 1-MCP. [ABSTRACT FROM AUTHOR]

• Antioxidant compounds of early-to-late apricots were predicted using ATR-FTIR and PLS. • Very good multi-cultivar models were developed for total phenols and flavans. • MIR predicted the parameters better than NIR. Vibrational spectroscopy is considered a green alternative to the traditional analytical methods for quantitative determination of antioxidants in agricultural products. In this study, the potential of NIR and MIR spectroscopy for the prediction of antioxidant compounds in seven early-to-late apricot genotypes from different locations was reported. NIR and MIR calibration models were developed using Partial Least Squares Regression (PLS) with cross-validation, and the performance of final models was evaluated using Rp2, root mean square error of prediction (RMSEP) and relative predicted determinant (RPD). Five independent PLS models were developed, using both NIR and MIR spectra from 300 samples per year and their corresponding total phenols (TPs), total flavans (FLs), total carotenoids (TCs), antiradical capacity (AC) reference values, yielding coefficient on average always > 0.95. Very good models were obtained for TPs (Rp2 = 0.99, RMSEP = 0.73 g kg−1 GAE, RPD = 12.0; Rp2 = 0.99, RMSEP = 0.95 g kg−1 GAE, RPD = 9.9 for MIR and NIR models, respectively), and FLs (Rp2 = 0.99, RMSEP = 0.99 g kg−1 CAT, RPD = 8.5; Rp2 = 0.98, RMSEP = 1.10 g kg−1 CAT, RPD = 6.4, for MIR and NIR models, respectively). Besides, both MIR and NIR models for total carotenoids (TCs) quantification showed a satisfactorily predictive capability (Rp2 = 0.98, RMSEP = 0.01 g kg-1 β-carotene, RPD = 6.5; Rp2 = 0.95, RMSEP = 0.01 g kg-1 β-carotene, RPD = 4.5, for MIR and NIR models, respectively). Good model performances were also obtained for the prediction of antiradical potential of samples, developed herein for the first time on freeze-dried apricot samples. In general, ATR-MIR demonstrated advantages over NIR in predicting all nutraceutical parameters, whereas similar model performances were obtained for the antiradical potential tested versus ABTS+• using MIR and NIR spectral regions. Results reported in the present study suggest that vibrational spectroscopy, both in MIR and NIR range, is adequate to predict the nutraceutical properties of apricots for screening purposes quickly and sustainably. [ABSTRACT FROM AUTHOR]

Basil seed gum (BSG) edible films containing with Origanum vulgare subsp . viride essential oil (OEO) (1–6%) were formulated in order to coating of fresh cut apricots. Chemical attributes, microbial load and sensory characteristics of coated fresh apricot-cut during cold storage at 4 °C for 8 d were investigated. The addition of OEO significantly decreased water vapor permeability (WVP) of films while increased their moisture content (p < 0.05).The applied coatings reduced total plate count, yeasts and molds populations. Among all tested treatments, the BSG +6% OEO was determined as the most effective in reducing the microbial populations of apricot cuts. In comparison with the control, total soluble phenolic and antioxidant activity of OEO added samples was enhanced significantly at the end of cold storage. The new introduced incorporated OEO BSG film and coating could provide great improvement in terms of odor and overall acceptability and it could be applied in order to maintain quality of fresh apricot cuts. [ABSTRACT FROM AUTHOR]

'Xiao bai' apricots taste excellent and are mainly produced in Northwest China. Apricots are very popular throughout China, so before sale, air transportation has become necessary. During transportation, mechanical vibration induces various physiological damages to the fruit. This is one of the main causes of the softening of apricots. The prevention and control of post-harvest transportation damage through non-thermal treatment is a promising physical preservation technology. In this study, the changes of cell wall characteristics of apricot stored under intense pulsed light (IPL) treatment was investigated before simulating transport vibrations. The IPL treatment improved the quality of apricots, reduced the content of malondialdehyde and hydrogen peroxide, significantly inhibited the activity of cell wall modifying enzymes, delayed the dissolution of water-soluble pectin and the degradation of cellulose, and inhibited the migration and change of water. Transmission electron microscopy imaging showed that the IPL treatment helped preserve cell wall structure, which was uniform and complete with high electron density. These results showed that IPL treatment inhibited the mechanical damage and adverse physiological changes to apricots subjected to vibration and prolonged their shelf life. [Display omitted] • Vibration damage causes postharvest quality loss of apricot. • IPL improved the softening of apricots caused by vibration. • IPL treatments inhibited water migration and loss of apricots caused by vibration. [ABSTRACT FROM AUTHOR]

Apricots are characterised by a rapid softening after harvest, resulting in a high susceptibility to mechanical damage and decay risk. Postharvest tools that accelerate or slow ripening can improve fruit quality to meet consumer preferences without impairing the supply chain. This study aimed to evaluate the effect of 1.0 µL L−1 1-methylcyclopropene (1-MCP) and 1000 µL L−1 ethylene treatment on 'Bergarouge®', 'Farely' and 'Swired' apricots. The influence of maturity at harvest was also investigated, focusing on softening and the texture change. The results showed that 1-MCP reduced softening of the three cultivars, independent of the maturity stage. Ethylene, applied during the shelf life, accelerated softening of 'Bergarouge®' and 'Farely', but it did not influence the firmness of 'Swired'. Both treatments had little or no influence on other quality parameters, such as the total soluble solids, titratable acidity and skin colour. The textural properties of the flesh and skin changed in a cultivar-dependent manner. Further, 1-MCP and ethylene treatments influenced these parameters differently according to the cultivar and maturity stage. Taken together, these results demonstrate that the cultivar is the most important factor in the effectiveness of 1-MCP and ethylene treatments to slow down or accelerate apricot softening after harvest. Texturometry enabled a better understanding of how the maturity stage and postharvest treatments influence the softening of apricots in a cultivar-specific manner. • Apricot softening was influenced mainly by the cultivar. • 1-MCP treatment reduced softening. • Softening was more rapid after ethylene treatment. • Texturometry enables a deeper understanding of texture evolution after harvest. [ABSTRACT FROM AUTHOR]

Biological control of postharvest transportation by non-thermal treatment is considered a promising physical preservation technology. This study investigated how apricot quality (before simulation of transport vibrations) increased using intense pulsed light (IPL) and dielectric barrier discharge plasma (DBD) techniques. The results showed that DBD and IPL treatments reduced damage to apricot fruit after vibration and inhibited microbial growth on the surface of apricot fruit. By increasing the content of non-enzymatic antioxidants (total phenols, total flavonoids, ABTS, and DPPH radical scavenging activity) and antioxidant enzyme activity (SOD, PPO, POD, and CAT), the antioxidant capacity of apricot fruit was increased, cell structure damage was reduced, and water migration and erosion were inhibited as well. In summary, DBD and IPL treatments inhibited adverse physiological changes in apricot fruit subjected to vibration and mechanical damage, maintained their sensory and nutritional quality, and extended their shelf life. [Display omitted] • Vibration damage causes postharvest quality loss of apricot. • DBD or IPL ameliorated the reduction in apricot quality caused by vibration. • DBD or IPL treatments effectively increased antioxidant capacity. • DBD or IPL treatments inhibited water migration and loss. • IPL produced better-quality characteristics than DBD treatment. [ABSTRACT FROM AUTHOR]

Enhancement of chilling tolerance has been observed in fruits treated with oxalic acid (OA). To learn how OA may play a role in modulating chilling injury in apricot, the fruit were treated with OA (5 mM) and stored at 2 ± 1 °C for five weeks. OA treatment significantly inhibited chilling injury, electrolyte leakage and accumulation of hydrogen peroxide and malondialdehyde in apricot fruit. Sorbitol, sucrose, fructose and glucose were the major soluble sugars in the fruit. Contents of glucose and fructose were enhanced, meanwhile, the levels of sucrose and sorbitole were decreased by OA treatment during storage. OA treatment enhanced activities of the enzymes related to increasing glucose and fructose, and suppressed sucrose synthase synthesis activity which could explain the lower content of sucrose. The activities of sucrose synthase cleavage function, acid invertase, NAD + -sorbitol dehydrogenase and sorbitol oxidase were significantly enhanced by OA. Meanwhile, OA-treated apricot fruit showed lower sucrose synthase synthesis activity. The degradation of sorbitol in apricot fruit was accelerated by OA treatment. Our results indicate that higher chilling tolerance of OA treated fruit was associated with higher content of reducing sugars (glucose and fructose). [ABSTRACT FROM AUTHOR]

Highlights: [•] E. coli ATCC 25922 can serve as a suitable surrogate for E. coli O157:H7. [•] UV-C reduces E. coli on apricots by less than 1 log CFU/g in the commercial setting. [•] Fruit received largely varying UV-C doses at different surface locations. [•] A fruit rotation device is needed for more uniform UV-C dosage to fruit. [Copyright &y& Elsevier]

Highlights: [•] Three non-destructive measurement devices were used to measure maturity at harvest. [•] Firmness at harvest (FF0) had the most influence on final firmness (FFFinal). [•] FF0 and FFFinal relationship was useful to identify optimum harvest maturity. [•] Visible-near-infrared spectroscopy was recommended for fruit segregation. [Copyright &y& Elsevier]

• Low-cost LLBI method can be used to assess of apricot quality during ripening. • Skewness of backscattering region was able to predict the apricot firmness. • Saturation and backscattering regions data were successful in predicting TSS. The maturity level plays an essential role in the quality and shelf life of apricot. The present research aims to investigate the applicability and accuracy of the non-destructive laser light backscattering imaging method to predict the quality properties of apricot during ripening. The backscattering images of apricots were acquired at 650 nm in six stages of ripening. The images were segmented by two different thresholding techniques, and several space domain features were extracted from the segmented images. Artificial neural network (ANN), partial least squares regression (PLSR), and principle component analysis-artificial neural network (PCA-ANN) models were developed to predict the firmness and total soluble solids (TSS) of apricot using each of the extracted image features and their combination as input for the prediction models. Results revealed a high correlation between the extracted features from the backscattering images and the quality parameters of apricot during ripening. Modeling using ANN recorded better performance than PLSR. The highest coefficient of determination (R2) and the lowest root mean squared error (RMSE) of cross-validation were achieved with ANN as R2 CV = 0.974, RMSE CV = 3.482 and R2 CV = 0.963, RMSE CV = 1.146 for firmness and TSS, respectively. The results confirmed that the laser backscattering imaging method was successful in predicting the quality properties of apricot during ripening. [ABSTRACT FROM AUTHOR]

Apricots (Prunus armeniaca) were held in air storage at 0°C and ripened at 20°C, or ripened at 20°C straight after harvest, and changes in fruit quality quantified using postharvest and sensory evaluations. Maturity at harvest significantly affected flesh firmness and other quality factors. Mealiness and gel formation only developed in fruit that had been stored at low (0°C) temperatures. Mealiness did not develop until firmness dropped below approximately 20N, whereas gel formation began to develop when firmness was as high as 35N. Development of mealiness and loss of juiciness were correlated; however, slight mealiness was perceived when fruit were still considered juicy. Specific cultivar-related differences were evident in the changes in firmness and development of gel formation during and after cold storage. Fruit were less liked by the sensory panel when firmness dropped below 20N, as juiciness decreased and mealiness and gel formation increased. Cell wall studies showed changes in yields of water-soluble and CDTA (trans-1,2-cyclohexanediamine tetraacetic acid)-soluble pectin. In fruit ripened after cold storage, mealiness and gel formation was accompanied by an increase in water-soluble pectin and an increase in CDTA-soluble pectin, whereas in apricots ripened straight after harvest, water-soluble pectin increased but CDTA-soluble pectin slightly decreased. All fruit, regardless of maturity or having chilling disorders or not, fitted the same correlation between firmness and uronic acid content of water-soluble pectin, but no pattern was evident for CDTA-soluble pectin. We concluded that the increasing solubilisation of pectin was a major feature of fruit softening in apricot, whereas the differences in CDTA-soluble pectin may reflect differences in strength of cell adhesion. [ABSTRACT FROM AUTHOR]

Abstract: Apricots are climacteric fruits with a high susceptibility to flesh softening and loss of flavor during postharvest storage, and most of the ripening processes are regulated by ethylene, which also has an effect on its own biosynthesis. To understand this process in apricot, inhibition of ethylene biosynthesis and perception was performed for studying key genes involved in the ethylene biosynthetic pathway. Apricots, cv. “Patterson”, were harvested with yellow-green ground color and immediately treated with either the ethylene perception inhibitor 1-methyl cyclopropene (1-MCP) at 10μLL−1 or the ethylene biosynthesis inhibitor aminoethoxyvinylglycine (AVG) at 1gL−1. After treatment, quality and physiological attributes such as firmness, color, total soluble solids, acidity, fruit weight, ethylene production and respiration rates were evaluated every 2d until they ripened at 20°C. Gene expression analysis was performed by quantitative polymerase chain reaction (qPCR). Both ethylene inhibitors were effective in reducing ethylene production, respiration rate and fruit softening. Three 1-aminocyclopropane-1-carboxylic-acid synthase (ACS) genes were characterized, but only the expression of ACS2 was highly reduced by ethylene inhibition, suggesting a key role in ethylene synthesis at ripening. Contrarily, ACS1 and ACS3 showed a higher expression under ethylene inhibition suggesting that the corresponding genes are individually regulated in a specific mode as observed in other climacteric fruits. Finally, changes in 1-aminocyclopropane-1-carboxylic-acid oxidase genes did not show a consistent pattern of ethylene modulation. [Copyright &y& Elsevier]

Abstract: During fruit ripening a loss of firmness occurs, which is a key factor limiting postharvest life. In apricot, Prunus armeniaca L., a wide range of fruit firmness at commercial maturity has been observed in different cultivars. Endopolygalacturonase (endoPG) activity has been reported to be associated with differences in firmness in many fruit species, but never in apricot. In this paper, we reported the identification of an apricot cDNA (PaPG) coding for an endoPG-like protein with 393 amino acids. Protein sequence comparison with known polygalacturonases (PGs) revealed that multiple features as conserved domains and functional residues and a predicted signal peptide were present in PaPG. Moreover, a phylogenetic analysis of this and other plant PGs placed PaPG into a clade containing endoPGs expressed in fruit, abscission and dehiscence zones without a propeptide sequence, very close to PRF5 from peach (Prunus persica L. Batsch). PaPG gene expression increased during postharvest storage of the fruit, correlating with fruit softening and ethylene release, and it responded to exogenous ethylene treatments. We localized the PaPG gene in apricot linkage group 4 after genetic mapping based on SNP analysis, in a position apparently syntenic to the PRF5 locus from peach. Results obtained offer genetic evidence supporting the hypothesis that PaPG and PRF5 are orthologous genes, and consequently position PaPG as a gene of interest for studies on fruit softening in apricot, and contribute to the development of molecular tools for breeding apricots with longer shelf life. [Copyright &y& Elsevier]

One of the most important factors limiting apricot quality is the loss of flavor during storage, particularly overall aroma. To characterize fruit aroma, several techniques have been used, including both instrumental- and sensory-based methodologies. Despite the importance of aroma in fruit quality, limited information is available regarding the effects of long-term cold storage and ripening on the apricot’s volatile compound profile. The objective of this research was to characterize the aroma of two lots of Castlebrite apricots at different stages of initial maturity using gas chromatography–mass spectrometry (GC–MS), electronic nose (e-nose) analysis, and a sensory panel. GC measurements were performed on both intact fruit and ground fruit tissue. Evaluations were performed at harvest, after 15 or 30d of cold storage at 0°C under a normal air atmosphere and also after a simulated shelf-life period at 20°C. Among the volatiles identified by GC–MS, aldehydes and esters were the primary constituents of Castlebrite apricot aroma, and differences in volatile aroma profiles were observed between intact and ground fruit. Only the concentrations of aldehyde compounds, primarily hexanal, were different between maturity stages. Furthermore, the e-nose was able to successfully differentiate between the two different stages of fruit maturity examined, but only after simulated shelf-life storage. Interestingly, despite the changes detected by GC and the e-nose, the sensory panel could not identify any differences between apricots at different stages of maturity. [Copyright &y& Elsevier]

Abstract: The influence of 1-MCP on the response of apricots to mechanical injury (impact) and the potential involvement of oxidative stress was investigated. Apricots (Prunus armeniaca L. cv. Marietta) picked at an early ripening (commercial harvest) stage (11–11.5°Brix) were dropped from 30cm onto a flat, hard surface to simulate an impact injury; fruit were treated with 500nl1−1 1-MCP for 20h at 20°C before or after the impact injury. Injured fruit showed a substantial rise in ethylene production after 4 days, while in fruit treated with 1-MCP, this increase started after 6 days, with a production rate lower than that of injured fruit. Increase in the respiration rate was delayed for 1-MCP-treated injured fruit in comparison with untreated injured ones. Tissue softening was reduced by 1-MCP treatment, showing less tissue deformability. Scanning EM analysis of injured tissue revealed healthier cells in 1-MCP treated apricots. 1-MCP-treated the increase of superoxide dismutase activity (SOD) due to mechanical injury in the first 4 days and this behaviour was related to ethylene production. Peroxidase activity (POX) increased in injured tissue immediately but then remained stable; 1-MCP, particularly when applied before the impact, increased POX activity. These results indicate that using 1-MCP can control ripening acceleration of apricots induced by mechanical injury. SOD, POX, and ethylene relationships are discussed. [Copyright &y& Elsevier]

Abstract: Postharvest biologists and technologists often need to include a human dimension to the assessment of product quality. The simplest of the questions that can be asked about two treatments is whether or not the sensory properties are different. There are a number of different types of discrimination tests that can be used to answer this question. Among such tests the triangle test is often considered by researchers, but is invalid because of the heterogeneity found in biological products, such as fruit and vegetables. In the current study, the problems associated with triangle tests are demonstrated by manipulating flavor and texture in apple juice, and an alternative discrimination test, the R-index, is examined in a study comparing apricots and peaches with low, medium and high soluble solids content (SSC). Following the completion of the R-index test on apricots and peaches, the participants indicated their preference for two fruit from each SSC-treatment using a 150mm line scale anchored ‘dislike extremely’ to ‘like extremely’. Participants expressed significantly higher (p <0.05) liking for high sugar (14–15% SSC) over low sugar (9–10% SSC) apricots and peaches. However, discrimination tests using the R-index did not identify any significant difference between the treatments. The results indicate that discrimination tests (both triangle and R-index) are cognitively challenging for participants, and that biological variability associated with fruit and vegetables will often overwhelm attempts to identify statistically significant differences. [Copyright &y& Elsevier]

Apricot and peach fruit were harvested weekly for 2 years, beginning 4 weeks after full bloom until commercial maturity. Wounded and unwounded fruit were inoculated with Monilinia laxa at 105 conidia ml−1. Fruit were characterized by dry matter (%) and stage of pit hardening, and brown rot incidence was evaluated after 7 days at 20 °C. Results show three stages of different susceptibility to M. laxa infection for both apricots and peaches. In the first stage susceptibility were high, but decreased in the second stage (rest period) during which the pit hardening occurred and green fruit were also resistant to the high inoculum concentration. Finally, in the third stage, from 4 to 5 weeks before full ripeness, fruit increased their susceptibility to M. laxa. Wounded and unwounded fruit showed the same susceptibility to the pathogen during growth. In peaches, dry matter was negatively correlated with Monilinia rot incidence. [Copyright &y& Elsevier]

Apricot fruit (cv. San Castrese) picked at commercial harvest (14° Brix) were dropped from different heights (5, 10, 20, and 30 cm) onto a flat hard and smooth surface and impact injury was evaluated visually on the skin for 3–4 days at room temperature. The flesh under the impact area turned brown after 3 days in the fruit dropped from 30 cm, but no symptoms were observed on the peel. Ethylene started to rise after 12 h; even sound area on the opposite side produced more ethylene 6 h later. The effect of temperature at the impact time and after the impact was studied. Fruit were impacted at 18 °C and then placed at 4 °C or kept at 18 °C, or dropped at 4 °C and then kept at 4 °C or moved to 18 °C. Ethylene production was greatly affected by low temperature. Ethylene increased more in fruit which were impacted at 4 °C and moved to 18 °C, than in fruit which were kept continuously at 18 °C. Respiration was affected by temperature but not as greatly as ethylene production. L (lightness) and b (yellowness) values decreased significantly in the injured flesh compared to the sound flesh especially in fruit impacted at 4 °C and then moved to 18 °C. Good management of temperature can reduce the physiological response of the tissue to bruising and control the appearance of bruising symptoms. [Copyright &y& Elsevier]

‘Canino’ apricots and ‘Royal Zee’ plums were treated with 1000 nl l−1 1-methylcyclopropene (1-MCP) at 20 °C for 20 h following harvest before 0 °C storage. After 5 days storage for apricots and 10 days for plums and after 30 days storage for both, fruit were moved to 20 °C for ripening. In addition, apricots were stored for 20 days and then treated with 1-MCP concentrations of 10, 100 and 1000 nl l−1 at removal and held for ripening. Ethylene production and respiration rate, as well as fruit quality of apricots varied with treatment. Ethylene production was efficiently inhibited by 1000 nl l−1 1-MCP in fruit treated after storage but not in fruit treated before storage. Fruit softening was associated with ethylene production and affected by 1-MCP in a concentration dependent manner when treated after storage, while 1-MCP did not affect softening in prestorage treated fruit. The color change of fruit was ethylene-independent and not affected by 1-MCP. Internal flesh browning was decreased by 1-MCP regardless of the concentration when treated after storage, while it was enhanced in fruit treated before storage. Decay development in apricots was decreased by 1-MCP in a concentration dependent manner. Ethylene production and respiration in ‘Royal Zee’ plums was greatly inhibited by 1-MCP during ripening after both short-term (10 day) and long term (30 day) storage. Parameters associated with ripening processes were decreased significantly by 1-MCP, including softening, color change, and loss of titratable acidity. These data demonstrate that 1-MCP has potential to delay ripening of apricots and plums, but the cultivar, maturity of fruit, and time of application must be chosen carefully. It is suggested that 1-MCP is more efficient for extending the shelf life and improving the quality of ‘Canino’ apricots directly marketed or after storage, whereas it might be a potent compound for extending both storage period and shelf life of ‘Royal Zee’ plums. [Copyright &y& Elsevier]

• The effects of storage temperature on Diaogan apricot were investigated. • Ice-temperature storage helped retain fruit firmness and pectin/cellulose content. • Ice-temperature storage enhanced the activities of antioxidant enzymes. • Ice-temperature storage ameliorated weight loss and respiration. • Ice-temperature is effective for maintaining apricot quality during storage. Ice-temperature storage is a new refrigeration method with temperatures ranging from sub-zero to the freezing point of the product being stored. However, few reports have evaluated the effects of ice-temperature (IT) storage on the cell wall metabolism and reactive oxygen metabolism of Xinjiang-grown Diaogan apricots. In this study, to determine the effects of ice-temperature storage on cell wall metabolism and reactive oxygen metabolism in Diaogan apricots, apricots were stored at −1.5 °C to−2.0 °C (ice temperature, IT), 0 °C–1 °C (low temperature), and 10 °C (control) for 70 d with sampling and evaluation every 10 d. Compared to storage at low temperature and 10 °C, IT storage (1) better maintained the firmness, ascorbic acid content, pectin content, and cellulose content of the fruit; (2) suppressed the activities of polygalacturonase and cellulase; (3) inhibited the rate of weight loss, respiration rate, ethylene production, plasma membrane permeability, and malondialdehyde accumulation; and (4) improved the activities of peroxidase, catalase, superoxide dismutase, and ascorbate peroxidase, thereby inhibiting the accumulation of hydrogen peroxide and superoxide anion during storage. Overall, the results show that IT storage is an effective way to improve the storage quality and antioxidant capacity of Diaogan apricots. [ABSTRACT FROM AUTHOR]

Preharvest MeSA treatment enhanced the chilling tolerance of apricot by regulating the sugar metabolism under chilling stress. [Display omitted] • Preharvest spraying with MeSA can improve the postharvest quality of apricot. • MeSA treatment can alleviate CI of apricot by regulating sugar metabolism. • Increased sucrose content is responsible for enhanced chilling tolerance of apricot. • MeSA can increase SPS and SS-S activities and inhibit AI, NI and SS-C activities. Apricot is highly susceptible to chilling injury during low temperature storage, while methyl salicylate (MeSA) can alleviate chilling injury and enhance the postharvest quality of fruit. The apricots were preharvest sprayed twice with 0.05 mmol L−1, 0.1 mmol L−1 and 0.2 mmol L−1 of MeSA solution, and then were harvested and stored at 2 °C (humidity of 70 %). After cold storage for every 4 d, apricots were transferred to 20 °C for 2 d to determine the fruit quality. Our results indicated that 0.2 mmol L−1 MeSA treatment exhibited the best efficacy. Preharvest MeSA treatment could reduce decay rate and chilling injury (CI) index, and maintain firmness, soluble solid content (SSC), organic acids and antioxidant capacities at a relative higher level. Preharvest MeSA treatment inhibited the increase of electrolyte leakage, malondialdehyde (MDA) and H 2 O 2 content in apricot. The chilling temperature of 2 °C could lead to the degradation of sucrose to fructose and glucose in apricot. At the same time, preharvest MeSA treatment effectively alleviated CI symptoms of apricot by reducing the degradation rate. The enhanced chilling tolerance of apricot treated with MeSA could be affected by the increased sucrose content, which was regulated by the higher activities of sucrose phosphate synthase (SPS) and sucrose synthase-synthesis (SS-S), and the lower activities of acid invertase (AI), neutral invertase (NI) and sucrose synthase-cleavage (SS-C). We proposed that preharvest MeSA treatment could enhance the chilling tolerance by regulating sugar metabolism and further improve the postharvest quality of apricot during low temperature storage. [ABSTRACT FROM AUTHOR]

• Fusion of scatter correction for NIRS modelling. • SPORT approach was used for the fusion. • Different scatter correction techniques provided complementary information. • Fusion works better in diffuse reflectance than transmittance measurement mode. Near-infrared spectroscopy (NIRS) is a key non-destructive technique for rapid assessment of the chemical properties of food materials. However, a major challenge with NIRS is the mixed physicochemical phenomena captured by the interaction of the light with the matter. The interaction often results in both absorption and scattering of the light. The overall NIRS signal therefore contains information related to the two phenomena mixed. To predict chemical properties such as dry matter, Brix and lipids, light refelction/absorption is used. Therefore, when the aim of the data analysis is to predict chemical components, it is necessary to remove as much as possible the scattering effects from the spectra. Several pre-processing techniques are available to do this, but it is often difficult to decide which one to choose. In this article we present the use of a recently developed pre-processing approach, sequential pre-processing through orthogonalization (SPORT), to improve the predictive power of multivariate models based on NIR spectra of food materials. The SPORT approach utilizes sequential orthogonalized partial least square regression (SOPLS) for the fusion of data blocks corresponding to several spectral preprocessing techniques. The results were compared with commonly used pre-processing techniques in the analysis of food materials by NIRS. The comparison was made by analyzing 5 different datasets comprised of apples, apricots, olive oils and grapes associated with chemical properties such as dry matter (DM), Brix, lipids and citric acid. The datasets were from both reflection and transmission measurements. The results showed that the fusion-based pre-processing methodology is an ideal choice for pre-processing of NIRS data. For four out of five datasets, the prediction accuracies (high R2 pred and low RMSEP) were improved. The improvement led to as much as a 20 % increase in R2 pred and a 25 % decrease in RMSEP compared to the standard 2nd derivative pre-processing. The pre-processing fusion was more effective for the reflection mode compared to the transmission mode. Multiple pre-processing techniques provided complementary information, and therefore, their fusion using the SPORT approach improved the model performance. The methodology is not only applicable to food materials but can in fact be used as a general pre-processing approach for all types of modeling of spectral data. [ABSTRACT FROM AUTHOR]

• Simulation model was developed to analyze RF selective heating of insects in dried apricots. • Thermal and dielectric properties of dried apricot flesh, pit and kernel were measured. • Simulated temperature distribution indicated good agreement with experimental data. • Differential heating of insects may result in effective RF disinfestation. In recent years, radio frequency (RF) dielectric heating has been increasingly studied as a promising novel disinfestation method for agricultural commodities, especially dried fruit. Three-dimensional multiphysics-based models have been established with a commercial finite element (FE) simulation package (COMSOL Multiphysics) to analyze the RF disinfestation process of dried apricots by defining six sub-domains: the flesh, a thin air layer, pit, air layer, kernel, and Indian meal moth larva located on the apricot surface. Thermo-physical and dielectric properties of the apricot flesh, pit and kernel were measured, respectively, by considering the heterogeneous structures of each individual dried fruit. The models were then experimentally validated by RF heating (27.12 MHz, 6 kW) 0.2 kg dried apricots filled in a rectangular container. The simulated point temperatures matched well with the experimental results both for the dried apricots and larvae, with a smallest average relative percentage error (RPE) of 1.45 %. Spatial distributions of simulated temperatures also indicated good agreement with the available experimental data, indicating that the maximum temperature of insect larvae was 11.3 °C higher than that of the flesh. Model prediction results demonstrated that compared with other physical locations (insect in perfect/partial contact with the flesh), the focusing effect of electric fields caused relatively fast heating rate (10.2 °C min−1) and high average temperature (68 °C) when the insects were located on the fruit surface (in point contact with flesh). Thus, the focusing effect of electric fields within insect body plays an important role in efficacy of RF disinfestation treatment for dried fruit. [ABSTRACT FROM AUTHOR]

• A new KMnO 4 -based C 2 H 4 scavenger using sepiolite as support material was developed. • The C 2 H 4 scavenging effect was more evident at 15 °C in air than at 2 °C in MAP. • Apricot softening was not found to be affected by C 2 H 4 removal. • Apricot sensory quality was kept during storage by using the KMnO 4 -loaded sepiolite. • The KMnO 4 -loaded sepiolite led to a reduced fungal incidence at 2 °C. A new potassium permanganate–based ethylene (C 2 H 4) scavenger was developed using sepiolite as support material. The effects of the scavenger on the main quality attributes of 'Mirlo naranja' apricots were evaluated in combination with modified atmosphere packaging (MAP) at 2 °C and under air packaging conditions at 15 °C. In–package gas composition, physicochemical traits (weight loss, fruit firmness, skin colour, pH, titratable acidity (TA), soluble solid content (SSC) and SSC/TA ratio, fungal incidence and sensory analysis), were monitored throughout storage. Results were compared with those obtained by using a commercial scavenger. As control, no scavengers were used. The results showed that both scavengers could achieve undetectable C 2 H 4 concentrations within MAP packages at 2 °C. Overall, C 2 H 4 removal resulted in a significant decrease in fruit weight loss, delayed TA decrease and led to lower SSC/TA ratio increase, while no effect was observed on fruit softening. In addition, the 15 °C–stored apricots also exhibited a lower pH increase, a decrease in C* colour parameter and less fungal incidence as a consequence of a C 2 H 4 –free environment. Furthermore, the developed scavenger reduced SSC changes of 15 °C–stored fruit, delayed fungal incidence at 2 °C, and maintained higher sensory quality during storage, maintaining good quality up to 36 d at 2 °C or 14 d at 15 °C. Accordingly, the developed C 2 H 4 scavenger could be a good mean to delay ripening process of fresh apricots, and probably other C 2 H 4 sensitive fruit, prolonging their postharvest storability and improving consumer acceptability. [ABSTRACT FROM AUTHOR]