Fruit Surface Research Articles

CFD Analysis of UV-C Intensity Radiation Distribution and Inactivation of Foodborne Pathogens on Whole and Minimally Processed Mango

Ultraviolet shortwave (UV-C) is a technology for postharvest fruit disinfection. This study aimed to use computational fluid dynamics (CFD) based on the discrete ordinate (DO) radiation model to analyze the distribution of UV-C intensity on whole and minimally processed mangoes within a disinfection chamber and to predict treatments against foodborne pathogens. The mango spears were oriented both parallel and perpendicular to the lamp and positioned at varying distances from the radiation source (50, 75, and 100 mm for spears and 100 mm for whole fruit). CFD simulations integrated with in vitro kinetic parameters enabled predictions of the time and doses needed to inactivate one to three logarithmic units of pathogens on the fruit surface. The highest average radiation intensity values were recorded for the whole mango oriented parallel to the lamp at 100 mm and the spears oriented normally to the lamp at 50 mm. The estimated times to achieve inactivation of one to three logarithmic units of microorganisms ranged from approximately 15 to 6540 s, while the doses necessary for this inactivation were, on average, 1.854, 5.291, and 10.656 kJ/m2, respectively. CFD simulations are valuable for optimizing UV-C treatments in large-scale designing from both microbicide and sustainable perspectives.

“AgriVision” A Flutter -Based Application for RealTime Detection of Pesticides Residues on Fruits

“AgriVision” is a Flutter-based mobile application designed to address the critical issue of pesticide contamination on fruits. The application utilizes real-time image processing and machine learning techniques to detect pesticide residues on the surface of various fruits, ensuring food safety and healthstandards. By capturing and analyzing images through a smartphone camera, the app provides instant and reliablefeedback on the presence of harmful chemicals. The user-friendly interface, combined with the portability of the solution, offers farmers, consumers, and vendors a practical tool to assess fruit quality and promote safer agricultural practices. This project aims to contribute to healthier food choices and enhance consumer safety. Key Words: AgriVision , Flutter application , Real-time detection , Pesticide residues , Fruits , Agricultural technology , Pesticide detection , Mobile app , Food safety , AgriTech , Image processing , Machine learning , Smart agriculture , Fruit quality analysis.

Production and characterization of biosurfactants from lactic acid bacteria in Dadiah for strawberries edible coating

Biosurfactants are amphiphilic components applied in various fields, one of which is preserving agricultural products. Biosurfactants can be used as additives in edible coatings to prevent microbial adhesion by reducing surface tension on the fruit surface. They also play a role in increasing the moisture barrier and slowing down the physiological changes of fruit. Nonetheless, biosurfactants were often produced by non-GRAS bacteria. GRAS biosurfactant-producing bacteria are urgently needed for application in food products. This study aims to isolate and characterize biosurfactant-producing strains of lactic acid bacteria from Dadiah and evaluate their efficacy in reducing microbial adhesion on strawberries. From four selected isolates found in Dadiah, Lactiplantibacillus plantarum was the best candidate, producing biosurfactant with index emulsification (EI24) of 64.48 ± 0.37% with a CMC of 1 g/l. LC-MS and FT-IR characterized the biosurfactants as glycolipids. The rate of antibacterial and anti-adhesive tests on Escherichia coli ATCC 8739 were 18.79 ± 5.23% and 55.26 ± 0.02%, while on Staphylococcus aureus ATCC 6738 were 31.60 ± 2.63% and 74.63 ± 0.00% at a concentration of 3000 mg/l. However, no anti-fungal activity against Rhizopus stolonifer and Aspergillus niger was observed at the same concentration. Compared to SDS, biosurfactants demonstrated non-toxicity with an LC50 value of 2.94 x 108 mg/l. A combination of 1% chitosan reduced the number of fungal cells by 29.76 ± 3.25% on 125 mg/l biosurfactant and bacterial cells by 31.91 ± 5.06% on 1000 mg/l biosurfactant after 10 days, indicating their potential to reduce fruit spoilage and enhance microbial anti-adhesive properties of edible coatings.

MICROMORPHOLOGICAL STUDIES (ACHENE / CYPSELA) ON SELECTED ASTERACEAE TAXA NATIVE TO TURKIYE

With this study fruit width-length measurements, weights and surface morphologies of some taxa belonging to Asteraceae family distributed in Türkiye were studied. The aim of the study was to reveal the fruit morphological characteristics and differences between the taxa of Tragopogon buphthalmoides, Dittrichia viscosa, Dittrichia graveolens, Tripleurospermum caucasicum, Kemulariella caucasica, Leontodon hispidus subsp. hispidus, Jurinea consanguinea and Jurinea moschus. Widths and lengths of the fruits were measured with Leica EZ4 microscope and digital caliper. Fruit weights were weighted out with Dikomsan precision scales. The stereomicroscope to determine the morphological characteristics of the fruits was also used. Scanning Electron Microscopy (SEM) in USKIM (Center for University and Industry Collaboration) was used to determine the surface morphology of the fruits. The smallest fruits were determined in Dittrichia graveolens (0.40 mm wide and 1.23 mm long), while the largest fruits were determined in Tragopogon buphthalmoides (25.88 mm long and 1.62 mm wide). The heaviest fruits were measured in Jurinea consanguinea (0.0065 gr) and the slightest fruits in Dittrichia graveolens (0.000062 gr) taxa.

Development of advanced biopolymer thin films of Carboxymethyl cellulose, Silver, and Zinc Oxide nanoparticles for avocado fruit preservation applications

Nanomaterials in post-harvest preservation offer advantages such as non-toxicity, chemical residue-free protection, and effective inhibition of mold and bacteria. Due to their strong antimicrobial properties and their ability to form a thin nano-coating on fruit surfaces, even small amounts of nanoparticles provide extensive coverage, preventing microbial penetration. This technology significantly improves fruit quality and longevity during storage and transportation. In this work, we introduced an advanced biopolymer film of carboxymethyl cellulose (CMC) incorporating ZnO and Ag nanoparticles (NPs). Ag NPs and ZnO NPs demonstrated an outstanding antimicrobial inhibition property that can be used for fruit preservation. As a proof of concept, the biopolymer thin films enable to extend avocado ripening from up to 35 days. The sugar concentration variation, the hardness, and the weight loss of the avocado with and without the advanced biopolymer thin film integrated ZnO and Ag nanoparticles in 35 days were compared with each other to clarify the ripening reduction ability of the biopolymer thin film.

Improving Yield and Quality of ‘Balady’ Mandarin Trees by Using Shading Techniques and Reflective Materials in Response to Climate Change Under Flood Irrigation Conditions

Considering climate change predictions, it is logical to anticipate detrimental effects on the mandarin tree, an essential citrus crop. Therefore, scientists should promptly focus on developing methods to enhance its resistance to climatic stress effects such as sunscald. This study assesses the strategies employed in ‘Balady’ mandarin trees when covered by shading nets of varying colors and percentages (white 50%, green 50% or 63%, black 50% or 63%), as well as the application of reflective materials (kaolin at 4% and CaCO3 at 3%) on the micro-climate of orchards, leaf, and fruit surface temperatures, fruit sunburn%, productivity, and fruit quality. The results indicated that shade nets effectively reduced temperature and enhanced humidity, especially during the period from June to September, when compared to open-field treatments. Black shade nets, particularly those with a shading level of 63%, demonstrated the most notable decrease in canopy temperature and an elevation in humidity, surpassing the performance of green and white shade nets. The present study found that shade nets and reflecting materials like kaolin and calcium carbonate significantly reduced fruit sunburn. Trees without shade had a sunburn rate of 8.74%, while those with shade treatments suffered no sunburn. Kaolin foliar spray at a concentration of 4% and calcium carbonate at a concentration of 3% reduced sunburn incidence to 3.64% and 7.32%, respectively. These treatments also reduced the intensity of sunburn. All treatments increased fruit yield % compared to the control and yield efficiency (kg/m2), especially the trees covered with white shade net of a 50% shading rate provided the highest values (43.70 and 40.17%) and (5.24 and 5.47 kg/m2) compared to other treatments in both seasons, respectively. Trees covered with a white shade net of a 50% shading rate, followed by a green shade net of 50% and a 63% shading rate, as well as a black shade net of 50% and a 63% shading rate, tended to improve the physical and chemical fruit properties. Therefore, it could be recommended that trees be covered with a white shade net of a 50% shading rate or a green shade net of a 50 and 63% shading rate in summer months due to its beneficial impact on mitigating fruit sunburn damage and enhancing the productivity and quality of ‘‘Balady’’ mandarin trees. Hence, shade nets can be a beneficial technology to protect citrus fruits from sunburn without affecting fruit quality in commercial citrus farms.

CmSN Regulates Fruit Skin Netting Formation in Melon

Melon (Cucumis melo) includes more than ten botanical groups, many of which feature netting ornamentation on the surface of mature fruit. Ripe melons display a netted skin that signifies their ripeness and readiness for consumption. Previously, we identified SKIN NETTING (CmSN), which encodes an EamA-like transporter family protein, as the candidate gene controlling fruit skin netting formation in melon, while its biological functions remain unclear. In this study, we demonstrated that the expression of the CmSN gene was considerably lower in netted melons compared to smooth-skinned melons, indicating a negative correlation between CmSN expression and netting formation. Subsequently, we employed transient overexpression and virus-induced gene silencing (VIGS) experiments to explore the role of CmSN gene during fruit development. Overexpression of the CmSN gene inhibited netting development, whereas silencing it promoted netting formation. Using heterologous transformation in tomato, we further confirmed the effect of the CmSN gene on rind texture and toughness, as these tomatoes exhibited rougher and tougher skins. Analysis with near-isogenic lines (NILs) revealed that CmSN gene-bearing fruits (NIL_CmSN) possessed significantly harder rinds than the control smooth-skinned variety HB42, underscoring the role of CmSN in enhancing rind protection. Together, our research offers essential insights into the netting formation and genetic improvement of melon fruits.

Calcium carbonate treatments affect cultivation environment around the fruit surface and mitigate sunburn formation and rind puffing of satsuma mandarin fruits

Calcium carbonate treatments affect cultivation environment around the fruit surface and mitigate sunburn formation and rind puffing of satsuma mandarin fruits

Sun Protection as a Strategy for Managing Heat Stress in Avocado Trees.

The increasing incidence of heat stress due to global climate change poses a significant challenge to avocado (Persea americana) cultivation, particularly in regions with intense solar radiation. This review evaluates sun protection strategies, focusing on the efficacy of different sunscreen products such as kaolin, titanium dioxide, and calcium oxide in mitigating thermal stress in avocado trees. The application of these materials was shown to reduce leaf and fruit surface temperatures, improve photosynthetic efficiency, and enhance fruit quality by preventing sunburn and dehydration. Despite these benefits, challenges remain, including the optimal timing and dosage of application, and the potential residue impacts on fruit marketability. The review emphasizes the need for ongoing research to develop more effective formulations and to integrate these sun protection strategies with other agronomic practices. The role of extension services in educating producers about the proper use of these technologies is also highlighted as crucial for the successful adoption of sun protection measures in avocado farming.

Surface Molding Hydrogel Film Initiated by ZIF-8 with Ethylene Adsorption Performance for Preserving Perishable Fruits.

The quality deterioration of postharvest fruits is greatly influenced by ethylene, leading to food wastage worldwide. Therefore, it is urgent to develop an efficient packaging strategy to reduce ethylene concentration and prolong the shelf life of perishable fruits. In this work, a surface-molding hydrogel film was created using ZIF-8 in combination with carboxymethyl starch (CMS) and carboxymethyl chitosan (CMCS). Specifically, ZIF-8 is first anchored on CMS and then rapidly cross-linked in situ with CMCS, forming ZIF-8@CC on the fruit surface (within 10 s). The perfect tight-fitting effects of ZIF-8@CC were observed on various fruit surfaces with different roughness (Ra: ranges from 102 to 308 nm). ZIF-8@CC could absorb 57.3% endogenous ethylene from bananas, and the interaction mechanism between ethylene and ZIF-8 was studied by molecular dynamics simulations, providing insights into the ethylene adsorption capacity of ZIF-8@CC. Moreover, ZIF-8@CC presented excellent antibacterial properties and achieved satisfactory ultralong preservation effects on both nonclimatic and climatic fruits (12 days for strawberries and 14 days for bananas) at room temperature. Importantly, ZIF-8@CC is easily removed, washed, and degradable. These findings offer an efficient and potential food packing material with multifunctional properties for preserving perishable fruits.

Impacts of Fruit Frosting Coverage on Postharvest Softening of Prunes under Vibration Stress

The surface of prune fruit has a thick layer of frosting, which is easily damaged and lost during prunes harvest or postharvest handling, and there is no clear information on the effect of prune surface frost on postharvest storage quality. To investigate the effect of fruit frosting on the softening of prune fruits during storage under vibration stress, prunes were divided into three grades according to fruit frosting in this study and were vibrated for 8 h at a frequency of 5 Hz at 4 °C; then, samples were selected once every 8 d. The results showed that the heavy fruit frosting (HFF) group maintained higher hardness (21.47%), L* (20.85%), and total soluble solids (12.79%) levels at the end of storage and inhibited cell wall-modifying enzyme activities (polygalacturonase, pectin methylesterase, glycosidase, β-glucosidase, and cellulase) compared to frosting-less fruit (FF) group. This group also showed improved expression of key cell wall-modification genes (ADPG2, PME31, CESA1, BGAL3, XTH33, BGLU41) as well as chelate-soluble pectin (72.11%), Na2CO3-soluble pectin (42.83%), and cellulose (36.89%) solubilization and maintained lower water-soluble pectin (34.23%). Microscopic observations showed that the fruit frosting could delay the dissolution of pectin components and protect the cell wall structure. In summary, fruit frosting can effectively inhibit fruit softening and maintain fruit quality.

Carboxymethyl cellulose based edible nanocomposite coating with tunable functionalities and the application on the preservation of postharvest Satsuma mandarin fruit

This study introduces an innovative carboxymethyl cellulose (CMC)-based edible nanocomposite coating, with two-dimensional layered double hydroxide nanosheets (2D LDH-NSs) and shellac, engineered to address challenges in fruit preservation. The synergistic integration of shellac and LDH-NS into the CMC matrix is strategically designed with tunable functionalities, encompassing wettability, gas barrier, and tensile properties. Our findings reveal that incorporating shellac and LDH-NS significantly improves the coating's wettability on the mandarin fruit surface, thus bolstering its adherence and uniformity, alongside enhancing its water vapor barrier efficacy and influencing the oxygen permeability. The application of this novel edible nanocomposite coating on Satsuma mandarin (Citrus unshiu Marc.) fruits has yielded promising outcomes in prolonging postharvest shelf life while preserving essential quality attributes, including peel surface morphology, weight loss, hardness, color retention, and nutritional values. Our work signifies a significant leap forward for the edible coating technology and bolsters the postharvest preservation of perishable fruits.

An integrated approach for assessing the health risks of pesticide residues on apple: From field dynamics to human exposure

The apple (Malus domestica), a cultivated fruit extensively grown in temperate regions worldwide, is abundant in nutrients and phytochemicals that promote health. However, the application of pesticides in apple cultivation raises significant concern regarding their influence on food safety. This study investigated the dynamic behavior of five pesticides, including chlorpyrifos, imidacloprid, acetamiprid, carbendazim, prochloraz, in apple trees, utilizing both field experiments and predictive modeling to analyze their distribution, transfer, and degradation patterns. Results from the field experiment revealed that at harvest, the residue levels of the five pesticides on apple were below international and national maximum residue limits. The dynamiCROP modeling results, corresponding to the field trial findings, demonstrated that these pesticides exhibited comparable dissipation patterns across various environmental compartments. The primary sources of pesticides in apples were the air and the fruit surface up to 10 days after application, while the soil and leaf surface became the main sources over time. The transferred pesticides adhered to the apple fruits at varying rates and persist therein. Choosing pesticides with lower impact scores helped reduce the impacts on human health and the environment. The assessment of health risks associated with consuming apples containing pesticide residues suggested that the impact on human health is acceptable. These findings were crucial for apple producers, as they enable the optimization of pesticide application timing to ensure compliance with food safety standards and help improve pesticide management strategies in agriculture. This study is essential for minimizing the environmental impact of pesticides and enhancing sustainable agricultural practices.

Mixed genetic analysis of major genes plus multiple genes in pepper fruit surface folds

Mixed genetic analysis of major genes plus multiple genes in pepper fruit surface folds

Maple compounds prevent biofilm formation in Listeria monocytogenes via sortase inhibition.

The Pss exopolysaccharide (EPS) enhances the ability of the foodborne pathogen Listeria monocytogenes to colonize and persist on surfaces of fresh fruits and vegetables. Eradicating listeria within EPS-rich biofilms is challenging due to their increased tolerance to disinfectants, desiccation, and other stressors. Recently, we discovered that extracts of maple wood, including maple sap, are a potent source of antibiofilm agents. Maple lignans, such as nortrachelogenin-8'-O-β-D-glucopyranoside and lariciresinol, were found to inhibit the formation of, and promote the dispersion of pre-formed L. monocytogenes EPS biofilms. However, the mechanism remained unknown. Here, we report that these lignans do not affect Pss EPS synthesis or degradation. Instead, they promote EPS detachment, likely by interfering with an unidentified lectin that keeps EPS attached to the cell surfaces. Furthermore, the maple lignans inhibit the activity of L. monocytogenes sortase A (SrtA) in vitro. SrtA is a transpeptidase that covalently anchors surface proteins, including the Pss-specific lectin, to the cell wall peptidoglycan. Consistent with this, deletion of the srtA gene results in Pss EPS detachment from listerial cells. We also identified several additional maple compounds, including epicatechin gallate, isoscopoletin, scopoletin, and abscisic acid, which inhibit L. monocytogenes SrtA activity in vitro and prevent biofilm formation. Molecular modelling indicates that, despite their structural diversity, these compounds preferentially bind to the SrtA active site. Since maple products are abundant and safe for consumption, our finding that they prevent biofilm formation in L. monocytogenes offers a viable source for protecting fresh produce from this foodborne pathogen.

Thrips (Thysanoptera: Terebrantia) in Nectarine Orchards in North-East Spain: Species Diversity and Fruit Damage.

Thrips constitute one of the main nectarine pests, with damage either in flowering or before harvesting (silvering). Several species are associated with damage to flowers, but Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is the main species associated with summer damage in Europe. Tree canopies of nectarine orchards under organic and integrated management were sampled in Lleida and Girona at four key moments of the season (bud burst, full flowering, fruit setting stage, and colorization of the fruit) during 2021 and 2022 to determine the species composition in the area and the damage caused during fruit maturation. Adult individuals in flowers, leaves, and fruit surfaces were collected and identified, and silvering damage to the fruit surface was assessed in the Lleida area. Fifteen species in Lleida and 10 species in Girona were collected from the tree canopy. Organic orchards in Lleida showed lower populations and silvering damage levels when compared with integrated orchards. Thrips fuscipennis Haliday (Thysanoptera: Thripidae) 1836 was the main species in Lleida during harvest, and Frankliniella occidentalis (Pergande) 1895 was the main species in Girona. Due to their predominance, both species were associated with silvering damage during fruit maturation.

First report of Neopestalotiopsis clavispora Causing guava scab in China.

Psidium guajava L. is widely cultivated in southern China. In May 2021, guava scab on cv. Zhenzhu was observed in Zhanjiang (21.18° N, 110.21° E), Guangdong province, China. Guavascab was corky with ovoid or round lesions on the surfaces of green fruits. Gradually the lesions sunk. Disease incidence was estimated as 85% in 500 investigated plants in about 50 ha. Twenty diseased fruits were collected from twenty trees in the field. From each fruit the margin of the diseased tissues was cut into 2 mm × 2 mm pieces; surface disinfected with 75% ethanol and 2% sodium hypochlorite for 30 and 60 s, successively; and rinsed thrice with sterile water. The tissues were plated onto potato dextrose agar (PDA) medium and incubated at 28 ℃. Thirty-four isolates were obtained. Single-spore isolation method (Liu et al. 2021) was used to recover pure cultures of three isolates (PGNC-1, PGNC-2, and PGNC-3) . The colonies were initially white with cottony aerial mycelium at 7 days on PDA. Then, these colonies form black acervular conidiomata at 10 days. Conidia were clavate to fusiform, four-septate, straight or slightly curved, and measured 15.8 to 21.2 µm × 4.5 to 6.5 µm (n = 40). The three median cells were versicolored, whereas the basal and apical cells were hyaline. Conidia had a single basal appendage (4.5 to 5.5 µm long; n = 40) and three apical appendages (19.2 to 24.5 µm long; n = 40). The morphological characteristics of the isolates were consistent with the description of Neopestalotiopsisclavispora (Maharachchikumbura et al. 2012). Molecular identification was performed using PCR method with MightyAmp DNA Polymerase (Takara-Bio, Dalian, China) (Lu et al. 2012). Sequences were generated from the isolates using primers for the rDNA ITS (ITS1/ITS4), TEF1-α (EF1-728F/EF1-986R), and β-tubulin (T1/βt2b) loci (Maharachchikumbura et al. 2012). The sequences of the isolates were submitted to GenBank (ITS, OQ996557 to OQ996559; TEF, OR101037 to OR101039; β-tubulin, OR100971 to OR100973). The sequences of the isolates were 100% identical to the type strain MFLUCC12-0281 (accession nos. JX398979, JX399014, and JX399045) through BLAST analysis. The isolates clustered with N. clavispora (MFLUCC12-0280 and MFLUCC12-0281). N. clavispora and Pestalotiopsis clavispora are synonyms. The pathogenicity was tested in vivo. Plants (cv. Zhenzhu) were grown ( 3 years old) in a quarantine orchard at 25℃ to 32℃ with 60 to 80% relative humidity in May 2022. Disease-free green fruits were inoculated. Sterile cotton balls were immersed in the spore suspension (1 × 105 per mL) and sterile distilled water (control) for about 15 s before they were fixed on the wounded fruits with transparent tape. Five fruits on one plant per isolate were inoculated. Five fruits on one plant severed as control. The test was performed thrice. Disease symptoms were found on the inoculated fruits after 20 days, whereas the controls remained healthy. The pathogen was re-isolated from infected fruits and was phenotypically identical to the original isolates thus fulfilling Koch's postulates. Neopestalotiopsis or Pestalotiopsis spp. were reported to be the causal agents of guava scab in Colombia and in Hawaii (Keith et al. 2006; Solarte et al. 2018). N. clavispora has been reported to cause disease in a broad range of hosts (Ge et al. 2009; Chen et al. 2018), but not in guava. This is the first report of N. clavispora causing guava scab in China. There would be no harvest if this disease is left unmanaged.

First report on regression-based QSAR addressing pesticide dissipation half-life in plants: A step towards sustainable public health

The excessive use of pesticides (an important group of chemicals) in the agricultural as well as public sectors raises a health concern. Pesticides affect humans and other living organisms via the food chain. Therefore, it is very necessary to calculate the dissipation half-life of pesticides in plants. Experimental prediction of pesticide dissipation half-lives requires complex environmental conditions, high cost, and a long time. Thus, in-silico half-life predictions are suitable and the best alternative. Herein, a total of six PLS (partial least squares) models namely, M1 (overall), M2 (fruit), M3 (plant interior), M4 (leaf), M5 (plant surface), and M6 (whole plant) alongside two MLR (multiple linear regression) models i.e. M7 (fruit surface) and model M8 (straw) were generated using dissipation half-lives (log10(T1/2)) of pesticides in plants and their different parts. Models were constructed in strict accordance with the guidelines outlined by the Organization for Economic Co-operation and Development (OECD) and extensively validated using globally accepted validation metrics (determination coefficient (R2) = 0.610–0.795, leave-one-out (LOO) cross-validated correlation coefficient (Q2LOO) = 0.520–0.660, MAE-FITTED TRAIN (mean absolute error fitted train) = 0.119–0.148, MAE-LOOTRAIN = 0.132–0.177, predictive R2 or Q2F1 = 0.538–0.567, Q2F2 = 0.500–0.565, MAETEST = 0.122–0.232), confirming their accuracy, reliability, predictivity, and robustness. Lipophilicity, the presence of a cyclomatic ring, suphur, aromatic amine fragments, and chlorine atom fragments are responsible (+ve contribution) for high dissipation half-lives of pesticides in plants. In contrast, hydrophilicity, pyrazine fragments, and rotatable bonds reduce (−ve negative contribution) the dissipation half-lives of pesticides in plants. To address the real-world applicability, the models were employed to screen the PPDB (Pesticide Properties Database) database, which revealed the top 10 pesticides with the highest log(T1/2) in the whole plant and respective parts of the plant body. The present work will aid in developing safer and novel pesticides, regulatory risk assessment, various risk assessments for the sustenance of public health, screening of databases, and data-gap filling.

Postharvest Application of Different Coatings to Improve the Quality and Storage Stability of Papaya Fruit (Carica papaya L.) Cv. Red Lady

The Present investigation was carried out on title “Study on different post-harvest treatment for improving shelf life and quality of Papaya fruit (Carica papaya L.) cv. Red lady”. The Experiment was conducted in a Completely Randomized Design with 10 treatments viz. T0-Control, T1- Ethrel 500 ppm, T2- Ethrel 700 ppm, T3- Aloevera gel 1.0%, T4- Aloevera gel 1.5%, T5- Corn Starch 1.0%, T6- Corn Starch 1.5%, T7- Cassava Starch 1.0%, T8- Cassava Starch 1.5%, T9- (Corn Starch 1.5% + Cassava Starch 1.5%) and their three replications, during the year 2023. Aloevera gel 1.5% treated fruits showed the better results followed by the Aloevera gel 1.0%. This coating reduced the transpiration rate and slowed down the ethylene production and formed a layer on the surface of papaya fruits which helped in protection from microorganisms, fungus resulting in the increase in shelf life of fruits and storage quality. The Papaya fruits treated with Corn Starch 1.5% was also found to be significantly good treatments over the Control in respect of storage quality and shelf life of Papaya fruits during the storage. Based on the results obtained, it can be concluded that Aloevera gel 1.5% was found to be most appropriate treatment in papaya cv. Red Lady. Therefore, it can be used in Papaya cv. Red Lady for physiochemical traits ie., Physiological loss in weight, Decay percent, Fruit Firmness, Sensory Evaluation, Visual Appearance, TSS.

Design and Analysis of a Robotic Gripper Mechanism for Fruit Picking

A gripper is the critical component of the robot end effector for the automatic harvesting of fruit, which determines whether the fruit can be harvested intact or undamaged. In this paper, a robotic gripper mechanism based on three-finger and variable-angle design is designed and analyzed for spherical or cylindrical fruit picking. Among the three fingers of the mechanical gripper, two fingers are rotatable through a pair of synchronous gears to ensure enough contact area for the grasping surfaces, which adapt to fruits of different sizes, such as cherry, loquat, zucchini, and so on. Furthermore, the mathematical relationship between gripper driving force and finger gripping force is obtained by the kinematic analysis of the gripper to realize stable grasping, and a grasping index is employed for the structural parameter optimization of our gripper. The grasping motion is analyzed, and the kinematic simulations are carried out, when the driving speeds of the gripper are 5 mm/s, 10 mm/s, and 15 mm/s, respectively. The system transfer function related to driving speed is obtained by curve fitting. Then, the grasping experiments are conducted with various spherical and cylindrical fruit, of which the weights are between 8 and 300 g and the diameters are from 9 to 122 mm. The experimental results demonstrate that our gripper has good kinematic performance and fruit adaptability. At the same time, the grasping is stable and reliable while no obvious damage appears on the fruit surface.