Loss Of Firmness Research Articles

Pulse electric field pretreatment delays the texture deterioration of sweet persimmon (Diospyros kaki L.) during postharvest storage

The food industry is highly concerned with food processing and waste reduction sustainability. Therefore, it is essential to develop new technologies to minimize waste and extend the shelf life of products. In this study, pulsed electric field (PEF) treatments were used at 25, 50, and 100 kV/m to investigate the potential for reducing the postharvest softening of persimmons. The results showed that after storing for 28 days, the firmness loss under 50 kV/m was maintained at 58.40 ± 0.36%, whereas that in the untreated group was 87.6 ± 0.14 %. The mobility of bound water was higher in the 50 kV/m group than in the 25 kV/m and untreated groups. PEF treatment also effectively reduced electrolyte leakage. This research also showed that PEF treatment could help reduce respiration by 12.5–31.22 CO2 mL/h/kg—an effective delay of 50 kV/m for soft rot and texture deterioration. In summary, applying PEF technology was found capable of extending the shelf life of persimmons under refrigeration by up to 14 days compared with the untreated group.

Postharvest caffeic acid dipping enhances disease resistance and storage capacity of ‘Zaosu’ pear fruit via regulating phenylpropane metabolism

Caffeic acid, a naturally occurring and safe phenolic compound, acts as a precursor in lignin synthesis within the phenylpropane metabolism pathway. The aims of this study was to evaluate the impacts of postharvest caffeic acid immersion on Alternaria rot and postharvest quality of ‘Zaosu’ pear fruit, as well as elucidate the underlying mechanisms involved. Results showed that postharvest caffeic acid dipping effectively inhibited spore germination and colony diameter of Alternaria alternata, as well as lesion diameter in A. alternata-inoculated pears. Caffeic acid treatment also delayed the increase of weight loss and decline in flesh firmness, increased total soluble solids content, and reduced surface yellowing of pears. Additionally, caffeic acid treatment enhanced the enzymatic activities and gene transcription levels of phenylalanine ammonialyase, 4-coumarate/coenzyme A ligase, cinnamate 4-hydroxylase, peroxidase, cinnamyl alcohol dehydrogenase, and polyphenol oxidase in pears. Meanwhile, the transcription levels of p-coumarate-3-hydroxylase, caffeic acid O-methyltransferase, cinnamoyl CoA reductase, caffeoyl shikimate esterase, hydroxycinnamoyl CoA: shikimate hydroxycinnamoyl transferase, caffeoyl CoA O-methyltransferase, ferulic acid 5-hydroxylase, and laccase genes were also up-regulated by caffeic acid treatment in pears. Furthermore, caffeic acid dipping enhanced phenylalanine, flavonoids, caffeic acid, total phenolic compounds, and lignin levels in the fruit. Therefore, caffeic acid exhibits promising potential for enhancing resistance against A. alternata and maintaining the storage capacity of pears via inducing phenylpropane metabolism.

Post-harvest management and characteristics of melon cultivars fruits and their prospects in the Roraima savannah: a review

The melon (Cucumis melo L.) holds significant economic importance on the global stage, with Brazil standing out as a strong exporter. Climatic conditions such as high temperatures, low relative humidity, and extended periods of sunlight are beneficial for the fruit's production and quality. The Northeast region of Roraima, particularly the municipalities of Bonfim and Normandia, close to the border with Guyana, has a semi-arid climate with an average annual rainfall between 1,200 and 1,400 mm. After harvesting, horticultural products begin to respire, a process that compromises post-harvest quality, leading to a decrease in organoleptic characteristics, firmness, sugar content, and loss of mass. The Cantaloupensis and Reticulatus melons, which are climacteric, have a high synthesis of ethylene and high respiratory rates in the fruit, resulting in flavor deterioration, firmness loss, and a shorter post-harvest shelf life. In contrast, non-climacteric melons, such as the inodorus group, display reduced ethylene synthesis, white flesh, subtle aroma, no pronounced ripening, and a longer post-harvest lifespan. It's worth noting that the melon market offers a variety of significant cultivars, resistant to pests, with high productivity and excellent post-harvest quality. This study aimed to address a literature review on the management of melon cultivation, development conditions of the crop, and post-harvest of melon cultivars in the Roraima Savanna."

Evaluating the quality of green asparagus treated with cassava starch-based coating using laser scattering

AbstractThe presented study investigated the effects of edible coatings with concentration of 2%, 3% and 4% of starch (w/v) on the weight loss and firmness loss of green asparagus during 4 days of storage at room temperature (26 ± 2 °C, 65–70% RH). According to the results, the coated asparagus exhibited significantly slower deterioration rate than the uncoated control samples. This was indicated by the decrease in weight loss and increase in firmness (P < 0.05). After the storage period, the samples treated with 4% starch formula retained the highest quality. Furthermore, the assessment of asparagus quality throughout the storage period involved the use of the line laser scattering technique. Extracted parameters of laser scattering signal discriminated samples with linear discriminant analysis (LDA), in which the correct recognition rate of the treated groups was 75.26% and the storage time was 70.54%. This study showed the potential of laser scattering as a rapid, non-invasive, and practical optical method for assessing the quality of asparagus during storage.

Carboxymethyl chitosan and polycaprolactone-based rapid in-situ packaging for fruit preservation by solution blow spinning

Nanofiber packaging has not yet gained practical application in fruit preservation because of some limitations, such as low production rate and utilization, and failure due to poor adhesion to the fruit. Herein, to solve this issue, a novel fruit packaging method based on solution blow spinning (SBS), called in-situ packaging, was pioneered. Specifically, carboxymethyl chitosan (CMCH) and polycaprolactone (PCL) were chosen as substrate materials and cherry tomatoes were selected as demonstration subjects. CMCH/PCL nanofibers were deposited directly onto the surface of cherry tomatoes by SBS, forming a tightly adherent and stable fiber coating in 8 min. Also, this in-situ packaging could be easily peeled off by hand. The in-situ packaging was an excellent carrier for active substances and was effective in inhibiting gray mold on cherry tomatoes. The in-situ packaging film formed a barrier on the surface of cherry tomatoes to limit moisture penetration, resulting in reduced respiration of fruits, which led to reduced weight and firmness loss. In addition, metabolomics and color analysis revealed that the in-situ packaging delayed ripening of cherry tomatoes after harvest. Overall, the in-situ packaging method developed in the present work provides a new solution for post-harvest fruit preservation.

A Hybrid Model for Detecting Insurance Fraud Using K-Means and Support Vector Machine Algorithms

Private stakeholders and governments across the globe are striving to improve the quality and access of healthcare services to citizens. The need to improve healthcare services, coupled with the increase in social awareness and improvement of people’s living standards, has seen an increase in medical policyholders in the insurance industry. Even so, the healthcare sector is grappled with increased costs every other year, leading to revision of premiums and increased costs for the policyholders. One of the main factors contributing to the increased costs is fraudulent claims raised by the service providers and the policyholders, leading to unprecedented risks and losses for insurance firms. The insurance industry has set up fraud detection and mitigation systems to mitigate losses brought about by fraudulent claims, which come in two flavors: rule-based systems and expert claims analysis. With rule-based systems, conditions such as missing details, location of the claim vis a vis the location of the policyholder, among other rules, are evaluated by systems to assess the validity of the claims. On the other hand, insurance firms rely on the human intervention of experts using statistical analyses and artificial rules to detect fraudulent claims. The rule-based and expert analysis methods fail to detect patterns or anomalies in claims, which is central to efficient fraud detection. Data mining and machine learning techniques are being leveraged to detect fraud. This automation presents enormous opportunities for identifying hidden patterns for further analysis by insurance firms. This research aims to analyze a hybrid approach to detect medical insurance fraud using both K-Means (unsupervised) and Support Vector Machines (supervised) machine learning algorithms.

Accrual-Based Earnings Management and the COVID-19 Pandemic

In this study, we document the accrual-based earnings management of Old Economy firms and New Economy firms (firms in the technology industry) and loss-making firms (firms with negative earnings in the pre-pandemic year, 2019) and profit firms in each economy, respectively, before, during, and in the recovery year of the COVID-19 pandemic. Using both univariate and difference-in-difference regression analyses, we find that old and new economy firms adopt different accrual-based earnings management, and Old Economy Loss firms changed their accrual-based earnings management the most during and in the recovery of the pandemic. During the 2020 pandemic, Old Economy Loss reported the lowest amount of accrual-based discretionary accruals. This suggests that Old Economy Loss firms are engaged in the most conservative approach to reporting their earnings, consistent with the big bath proposition. In the recovery year of the pandemic, 2021, we find that accrual-based earnings management reversed, with the old economy losing firms reporting the highest amounts of discretionary accruals. However, we do not find that the explanatory power of earnings on the variance of stock prices for the old economy loss firms is affected by their discretionary change in accounting accruals.

Transcriptome analysis reveals the mechanism of delayed softening of ‘France’ prune (Prunus domestica L.) during storage at near-freezing temperature

Rapid loss of firmness of ‘France’ prune after harvest limits the commercial potential of the fruit. Therefore, the present study aimed to explore the potential mechanism by which near-freezing temperature (NFT) maintains fruit quality and delays the softening of ‘France’ prune. We found NFT maintained higher fruit firmness (91.34 %), delayed the decomposition of cellulose (53.87 %) and hemicellulose (41.41 %), and inhibited the activity of softening-related enzymes compared with the control group. RNA-sequencing data showed that 4984 differentially expressed genes (DEGs) were detected in the control group (CK30)-vs-NFT group (B30) comparison. These DEGs are mainly involved in plant hormone signal transduction, secondary metabolite biosynthesis, galactose metabolism, and the pentose-glucuronate interconversion pathway. By screening and identifying DEGs, we found that the PG, PME, CEL, ACS, PER, UGT, and transcription factor (TF) genes (NAC089, ERF026, and NAC083) may be involved in the softening of ‘France’ prune. In conclusion, NFT delays the softening of ‘France’ prune likely by regulating the expression of related genes and metabolic pathways. These findings provide a theoretical basis for understanding the mechanism of NFT-mediated delay of ‘France’ prune fruit softening.

Effects of proteases on textural softening and changes in physical property of harpiosquillid mantis shrimp (Harpiosquilla raphidea) during the iced storage

SummaryRapid softening of texture is a major problem associated with quality loss and consumer rejection of harpiosquillid mantis shrimp (Harpiosquilla raphidea) (HMS). Effects of endogenous proteases in muscles and digestive tract on protein degradation and softening were investigated. Scanning electron microscopic and histological images indicated drastic destruction of muscle during iced storage. Based on autolysis, maximal activity was found at pH 8.5 and 55 °C, and serine proteases including trypsin were dominant. Cathepsin B and L + B in muscle were altered throughout storage, while trypsin remained constant in HMS meat for 1–3 days. Firmness and toughness decreased and coincided with augmented degradation of myofibrillar proteins and collagen. Trypsin from the digestive tract was contaminated into the abdomen during iced storage, therefore inducing drastic hydrolysis of muscle proteins. This phenomenon caused the undesirable pasty/mushy texture associated with the loss in firmness and toughness of meat within 3 days of storage.

Changes in Physicochemical Characteristics, Peel Color, and Juice Attributes of ‘Moro’ Blood Orange Fruit Treated with Glycine Betaine and Methyl Salicylate during Cold Quarantine Storage

Cold quarantine storage is the practice of subjecting citrus fruit to low temperatures after harvesting to comply with stringent international phytosanitary standards for export, but fruit quality can be affected during storage. Therefore, this study investigated the effects of glycine betaine (GB) and/or methyl salicylate (MeSA) on physicochemical changes, chemical attributes of juice, and peel color of ‘Moro’ blood orange at cold quarantine storage (2 °C) for 60 days. Fruit were treated with GB (15 and 30 mM) by vacuum infiltration at 30 kPa for 8 min and vapor treatment of MeSA (100 µM) for 18 h as well as the combination of both GB concentrations with MeSA. The key findings of this research revealed that the combined treatment of 30 mM GB and 100 µM MeSA significantly mitigated weight and firmness losses in ‘Moro’ blood orange fruit during the cold quarantine period. Furthermore, there was a decrease in titratable acidity (TA) across all treatments, with the highest TA recorded for the 30 mM GB + 100 µM MeSA combination. Conversely, total soluble solids (TSS), TSS/TA ratio, and juice pH increased in all treatments, with the control treatment displaying the highest values. Regarding peel color parameters, which encompass L* (lightness), b*, hue angle (h°), chroma (C*), and a*, as well as the citrus color index (CCI), these exhibited characteristic changes during cold quarantine storage. However, the application of GB and MeSA, especially at the 30 mM GB + 100 µM MeSA level, noticeably delayed these peel color variations. Overall, GB and MeSA treatments offer significant advantages in preserving the physicochemical characteristics and chemical attributes of ‘Moro’ blood oranges during cold quarantine storage. These findings underscore the potential of GB and MeSA treatments for maintaining the quality of ‘Moro’ blood oranges during cold quarantine storage, with a noteworthy synergistic effect between MeSA and GB in preserving fruit quality.

Alleviatory effects of salicylic acid on postharvest softening and cell wall degradation of 'Jinshayou' pummelo (Citrus maxima Merr.): A comparative physiological and transcriptomic analysis.

The regulatory mechanisms underlying the salicylic acid (SA)-mediated inhibition of senescence in pummelo fruit, the largest known citrus variety, remain unclear. Herein, postharvest 0.3% SA treatment was demonstrated to delay postharvest 'Jinshayou' pummelo senescence, as evidenced by the inhibitions in firmness loss, electrolyte leakage increase, and color change. Using comparative transcriptomic data, a total of 4367, 3769, and 1659 DEGs were identified between CK0 and CK60, CK0 and SA60, and CK60 and SA60, respectively. Further GO analysis revealed that DEGs were mainly implicated in the processes of cell wall modification and phenylpropanoid pathway during fruit senescence. More importantly, postharvest exogenous 0.3% SA treatment was observed to inhibit CWDEs activities and their encoding gene expression, retain higher protopectin, cellulose, and hemicelluloses contents, as well as reduce WSP content, thus maintaining cell wall structure. These findings collectively indicated that postharvest SA treatment was a green and useful preservative for alleviating fruit senescence and prolonging the storage life of harvested 'Jiashayou' pummelo fruit.

Comparative Physiological and Transcriptome Analyses Reveal Mechanisms of Salicylic-Acid-Reduced Postharvest Ripening in 'Hosui' Pears (Pyrus pyrifolia Nakai).

Postharvest ripening of sand pear fruit leads to quality deterioration, including changes in texture, flavor, and fruit color. Salicylic acid (SA), an important defense-related hormone, delays fruit ripening and maintains fruit quality, but the underling mechanism remains unclear. Herein, we evaluated the efficacy of SA in delaying the ripening process of Pyrus pyrifolia cv. 'Hosui' pear fruit, as evidenced by the reduction in fruit weight loss, inhibition of firmness loss, cell wall degradation and soluble sugars, and retention of total phenols. Based on comparative transcriptomic data, a total of 3837 and 1387 differentially expressed genes (DEGs) were identified during room-temperature storage of control fruit and between SA-treated and control fruit, respectively. Further KEGG analysis revealed that the DEGs were mainly implicated in plant hormone signal transduction, starch and sugar metabolism, and cell wall modification. Moreover, exogenous SA treatment also altered the expression of many transcription factor (TF) families, including those in the ethylene-responsive factor (ERF), NAM, ATAF, CUC (NAC), basic helix-loop-helix (bHLH), basic leucine zipper (bZIP), and v-myb avian myeloblastosis viral oncogene homolog (MYB) families. Together, the results offer important insights into the role of SA-responsive genes in controlling fruit ripening in sand pears.

Evaluation of Biocontrol Potential of Bacillus spp. and Pseudomonas fluorescens UM270 against Postharvest Fungal Pathogens

Fungal pathogens are the main causal agents of postharvest diseases of fruits and vegetables. To prevent this problem and avoid the use of harmful chemical fungicides, safer and greener alternatives have been sought. One of these alternatives is the use of plant-growth-promoting bacteria (PGPB). In this study, we evaluated in vitro four well-known PGPB strains (Pseudomonas fluorescens UM270, Bacillus toyonensis COPE52, Bacillus sp. E25, and Bacillus thuringiensis CR71) for their biocontrol potential against nineteen postharvest fungal pathogens. In vivo assays were also performed, and bacterial cells were inoculated on harvested strawberries and grapes with the pathogens Botrytis cinerea, Alternaria alternata, and Fusarium brachygibbosum to evaluate loss of firmness and disease incidence. Our results show that the four strains antagonized fungi in direct and indirect confrontation assays. Stronger antagonism was observed by the action of diffusible metabolites (DMs) compared to volatile organic compound (VOC) activity. All PGPB significantly improved the fruit firmness and reduced disease incidence caused by the fungal pathogens tested. However, strain UM270 showed excellent biocontrol activity, reducing the disease incidence of Fusarium brachygibbosum, Botrytis cinerea, and Alternaria alternata on strawberry fruits by 60%, 55%, and 65%, respectively. Diffusible antifungals and VOCs such as 2,4-diacetyl phloroglucinol, siderophores, auxins, fengycins, and N, N-dimethyl-hexadecyl amine, among others, might be responsible for the beneficial activities observed. These results suggest excellent biocontrol activities to inhibit postharvest pathogenic fungi and improve harvested fruit quality.

Variations of quality and volatile components of morels (Morchella sextelata) during storage

The postharvest senescence of morels was observed to be easily affected by temperature fluctuations. The objective of this study was to examine the influence of various storage temperatures on the postharvest senescence of morels. The study evaluated the variations of water content, respiration, nutrients substances, cell membrane permeability, and volatile compounds in morels stored at 20 °C and 4 °C. Results showed that low-temperature storage suppressed the loss of water and firmness, delayed the time of respiration and ethylene peak, and reduced the loss of nutrients and cell membrane permeability. Furthermore, the content of volatile compounds increased and then decreased during storage. The characteristic aroma substances of 1-octen-3-ol were identified using odor activity values and OPLS-DA analysis. The study observed a decrease in the content and changes of aroma compounds during low-temperature storage. This decrease may be attributed to the decreased activities of lipoxygenase (LOX) and alcohol dehydrogenase (ADH).

Effects of Exogenous Application of Glycine Betaine Treatment on 'Huangguoggan' Fruit during Postharvest Storage.

Loss of quality in citrus fruit is a common occurrence during postharvest storage due to oxidative stress and energy consumption. In recent years, glycine betaine (GB) has been widely applied to postharvest horticulture fruit. This study aimed to investigate the effect of GB treatment (10 mM and 20 mM) on the quality and antioxidant activity of 'Huangguogan' fruit during postharvest storage at room temperature. Our results indicated that both 10 mM and 20 mM treatments effectively reduced weight and firmness losses and maintained total soluble solid (TSS), titratable acidity (TA), and ascorbic acid contents. Additionally, GB treatment significantly increased the activity of antioxidant enzymes, maintained higher levels of total phenols and total flavonoids, and led to slower accumulation of H2O2. A transcriptome analysis conducted at 28 days after treatment (DAT)identified 391 differentially expressed genes (DEGs) between 20 mM GB (GB-2) and the control (CK) group. These DEGs were enriched in various pathways, particularly related to oxygen oxidoreductase, peroxidase activity, and flavonoid biosynthesis. Overall, the application of GB proved beneficial in enhancing the storability and extending the shelf life of 'Huangguogan' fruit.

Edible Coating Formulated by Optimization from Aloe vera, Starch, and Arabic Gum Improved the Conservation of Banana (Musa acuminata) Fruits.

Banana is a very perishable climacteric fruit with consequence of large postharvest losses. The objective of the present study was to improve the postharvest shelf life of bananas. Fruits from the Melong locality were treated with coating solutions formulated with a mixture of Aloe vera, starch, and Arabic gum at different concentrations. These concentrations were obtained using the response surface methodology in order to establish the relationship between independent variables (ripening parameters) and dependent variable (Aloe vera, starch and Arabic gum), which led to the generation of experimental design as well as the prediction of result model. The effects of the coating solutions were evaluated on firmness, percentage of ripening, weight loss, chlorophyll a, chlorophyll b, and total soluble solid contents. The results showed that the combination of Aloe vera, starch, and Arabic gum extended the shelf life of banana by slowing down the chlorophyll degradation, the loss of firmness, the weight loss, and the synthesis of total soluble solids. The coefficients of determination (R2) of the responses were all above 80% indicating that the experimental data fit well with the predicted responses. The interactions that influenced most of the responses were those between Aloe vera-starch and Aloe vera-Arabic gum. The optimum concentrations obtained for the mixture of the final solution were 286.799 ml.l-1 (v/v), 102.589 g.l-1 (m/v), and 1.0888% (m/v) for Aloe vera, starch, and Arabic gum, respectively.

Cold shock precooling improves the firmness of chili pepper during postharvest storage and the molecular mechanisms related to pectin.

This research was conducted to explore the influence of cold shock on the firmness, a quality marker in chili pepper during 0-21 d storage and determine mechanism by cold shock impacted pectin. Chili peppers were exposed to cold shock precooling (0±2°C water/ice mixture) for 0-, 30-, 90- and 150-min, respectively. Results showed that cold shock alleviated loss of firmness throughout storage. Firmness was positively associated with sodium carbonate-soluble pectin content (r=0.44), methylation degree of CDTA-soluble pectin (r=0.82) and water-soluble pectin (WSP, r=0.87), but negatively associated with WSP content (r=-0.76), and the activities of β-galactosidase (r=-0.72) and pectinlyase (r=-0.74). Cold shock for 90min was determined to be optimal. This study confirms the applicability of cold shock precooling to maintain firmness and thereby to extend the shelf life of chili pepper.

Determining the harvest time for 'Ubá' mangoes as a function of textural properties

Considering that the early harvest and the mechanical damages that occur during harvest and post-harvest are the main factors that compromise the quality and shelf life of mango fruits, this study aimed to evaluate the textural properties of 'Ubá' mango in different stages of maturation in order to define the best time to harvest the fruits for industrial use. A completely randomized design with ten replications was used. The fruits were acquired from a site located in the municipality of Guidoval-MG, Brazil, selected and classified into four stages of maturation: green, green, ripe and semi-ripe. The fruits were submitted to compression and penetration tests (penetration of the whole fruit, pulp and skin). In general, the advance of maturation resulted in a decrease in the maximum penetration force, which went from 57.37, 30.89 and 27.48 N to 11.79, 1.61 and 4.81 N, for the whole fruit. with rind, pulp and rind, in this order, the same occurring for the compression force that decreased from 277.27 to 32.51 N, from the green to the ripe stage, evidencing the loss of firmness of the fruits with ripening. Based on the research results, the 'Ubá' mango can be harvested at the verdoengo stage, as it has greater firmness than the semi-ripe and mature stages, but not as high as the green stage, an important attribute for handling in the stages and post-harvest procedures of the product.

Voluntary Disclosure, Moral Hazard, and Default Risk

We study a dynamic moral hazard setting where the manager has private evidence that predicts the firm’s cash flows. Bad-news disclosure is rewarded by a lower borrowing cost relative to the no-evidence case, whereas no disclosure leads to higher borrowing costs. For a given capital structure, disclosure reduces the firm’s default risk by lowering its pay-for-performance sensitivity. However, for a set of low-profitability firms, the anticipation of future disclosure of information by managers lowers both firm value and managerial rents at the financing stage because of a reduction in the firm’s initial liquidity. The model can reconcile the empirical evidence on the effects of providing earnings guidance, especially for loss firms. This paper was accepted by Bruno Biais, finance. Funding: S. Fu is supported by the Shanghai Pujiang Program and the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning [Grant 0900000182]. Supplemental Material: The data files are available at https://doi.org/10.1287/mnsc.2023.4860 .

All losses are not alike: Real versus accounting-driven reported losses

AbstractWe examine the value relevance of accounting-driven losses that result from the immediate expensing of firms’ internally generated intangible investments versus losses occurring irrespective of intangible investments. Contrary to the long-held view that losses are less relevant than profits for valuation, we find that once the accounting bias of intangibles-expensing is undone, earnings of firms reporting intangibles-driven losses are as informative as earnings of profitable firms. Furthermore, contrary to the view that persistent losses decrease earnings relevance, our evidence shows no decrease in the relevance of earnings for firms reporting persistent intangibles-driven losses. We also find that firms reporting intangibles-driven losses subsequently outperform other loss firms and even profitable firms in value creation from investments in technological innovation and human capital. Our evidence further shows that firms reporting intangibles-driven losses have stronger future performance than other firms. Taken together, the results of this study demonstrate the fundamental differences between losses driven by the immediate expensing of internally generated intangible investments and losses reflecting genuine business performance shortfalls. Standard accounting performance measures, however, do not properly reflect these operational differences and their implications.