Fruit Content Research Articles

Effect of Multi-Year Protection of Grapevines with Copper Pesticides on the Content of Heavy Metals in Soil, Leaves, and Fruit

This study evaluates the impact of multi-year protection of grapevines using copper-based pesticides on heavy metal content in soil, leaves, and fruit under organic and conventional cultivation methods. Conducted on Solaris, Hibernal, and Muscaris grapevine varieties in north-western Poland, the research highlights significant differences between the two cultivation approaches. In organic vineyards, copper content in soil averaged 10.25 mg/kg, significantly higher than the 9.05 mg/kg found in conventional soils. Manganese levels were also elevated in organic soils (223 mg/kg) compared to conventional ones (299 mg/kg). Conversely, conventional vineyards exhibited higher zinc and lead concentrations, averaging 47.10 mg/kg and 20.34 mg/kg, respectively, versus 43.50 mg/kg and 11.22 mg/kg in organic soils. The organic soils also had higher salinity (46.50 mg/kg) than conventional ones (30.50 mg/kg). The fruits of grapevines in organic cultivation showed higher copper and zinc levels, with the Solaris variety containing 15.01 mg/kg of copper and the Muscaris variety having 11.43 mg/kg of zinc. These levels exceed the commonly encountered ranges of <1 to 10 mg/kg. Lead content in fruits was higher in organic cultivation (2.19 mg/kg) than in conventional cultivation (1.18 mg/kg), occasionally surpassing the critical value for consumable plants (1 mg/kg). Leaves of grapevines from organic vineyards had significantly higher copper and manganese content than those from conventional vineyards, with the Hibernal variety showing the highest levels. These findings underscore the necessity for monitoring and managing heavy metal content in vineyard soils to ensure fruit quality and safety.

Non-destructive Evaluation of Oil Content and Carotene in Oil Palm Fresh Fruit Bunches Based on Optical Properties Using Partial Least Square (PLS)

Crude palm oil (CPO) is a raw material for making cooking oil that comes from palm oil, which is greatly influenced by the quality of oil palm fresh fruit bunches (FFB). Oil and carotene content in the FFB influence the quality of palm oil. The oil content is usually determined using a chemical method (Soxhlet extraction) which is time consuming and destructive. This research aimed to predict the oil and carotene content contained in oil palm FFB using partial least square (PLS). In this research, the sample used was the Tenera variety with a maturity of 140-160 day after anthesis (DAA) and 200-220 DAA. The nondestructive method involves recording images using an optical camera, which produces RGB and L*a*b* values. Results showed that PLS predicts the relationship between optical properties and oil and carotene content in palm oil. Non-destructive prediction results using PLS provided consistently correlation of L*a*b* values with estimated oil and carotene content in the FFB. Keywords: Non-destructive, Optical properties, Fresh fruit bunch, Oil palm.

Physiological and Transcriptomic Analysis of Citrus Fruit Segment Drying under Facility-Forcing Cultivation

Facility-forcing cultivation could effectively improve the quality of ‘Beni Madonna’ citrus (Citrus nankao × C. amakusa) and advance the ripening period. However, segment drying (KS) before harvest caused fruit quality deterioration and commodity value loss. In this research, we investigated the physiological and molecular characteristics involved in citrus segment drying under facility-forcing cultivation. The juice yield, sugar, acid, vitamin C, and lignin contents in KS fruits were significantly decreased, and the contents of pectin and cellulose were significantly increased. The relative contents of abscisic acid and abscisic acid glucosyl ester in KS fruits were significantly decreased. A total of 1215 differentially expressed genes (DEGs) were screened by transcriptome sequencing. DEGs were significantly enriched in water metabolism, sugar metabolism, transportation, cell wall and phenylpropanoid biosynthesis, and plant hormone signal transduction. The decrease in water absorption and sugar synthesis, the increase of pectin and cellulose synthesis, and the decrease in ABA accumulation may be the main reasons that cause citrus fruit segments to dry under facility-forcing cultivation.

Global analysis of spatio-temporal variation in mineral nutritional quality of pepper (Capsicum spp.) fruit and its regulatory variables: A meta-analysis

Pepper (Capsicum spp.) is an important fruit vegetable worldwide, and it is a rich dietary source of minerals for human being. Yet, the spatio-temporal distribution of pepper fruit mineral composition and the factors influencing such variations at global scale remain unknown. A global meta-analysis of 140 publications providing 649, 562, 690, 811 datapoints was conducted to quantify and evaluate the nutritional quality, comprising potassium (K), magnesium (Mg), iron (Fe) and zinc (Zn), of pepper fruits and its influencing variables. The analysis showed that the global average of K, Mg, Fe and Zn content in pepper fruits was 20–25 g kg−1, 1–1.5 g kg−1, 80–100 mg kg−1, and 20–40 mg kg−1, respectively. There had been a downward trend in pepper fruit nutritional quality over the last decade, especially for Fe and Zn. And, the concentration of all these four nutrients were at lower levels in less developed regions, especially in Africa. Our results showed that the vegetable “green pepper” contains more K, Mg, Fe and Zn than the “hot pepper” used as spice. The concentration of K, Mg, Fe and Zn were increased with fruit yield but that of Fe and Zn were decreased with increase in single fruit weight. Nutritional quality was optimal at mean annual temperature of 10 ℃ − 20 ℃, and was adversely affected when mean annual precipitation was < 500 mm. Pepper fruits produced at pH 6.5–7.5 had higher fruit K concentration while acidic soils (pH<6.5) favored higher Fe and Zn concentrations. The higher soil organic matter (SOM) generally improved the nutritional quality of the pepper. Our results suggest that systematic selection of superior varieties and soil amelioration (adjusting pH and SOM) of the soil-crop system are needed to achieve higher nutritional quality of pepper fruit.

Behavior of ponkan mandarin tree canopy grafted onto rangpur lime and flying dragon rootstocks

The Rangpur lime rootstock was the basis of Brazilian citrus growing for many years. However, this rootstock has been gradually replaced due to the occurrence of Citrus Sudden Death. The Flying Dragon rootstock has stood out as one of the options for replacement as it has different characteristics, such as reducing the size of the plant. There is no information in the literature about the behavior of Flying Dragon as a rootstock for Ponkan mandarin. Therefore, the objective of this study was to evaluate the behavior of Ponkan mandarin tree canopy grafted onto Rangpur lime and Flying Dragon rootstocks concerning physiological, agronomic, and fruit quality parameters. In the experiment, productivity, soil moisture, water potential, plant height, fruit diameter, fruit length, fruit mass, fruit pH, soluble solids content, titratable acidity, and ratio were evaluated. The Flying Dragon rootstock was responsible for the decrease in average productivity in the Ponkan mandarin culture. Greater plant heights were obtained when canopies were grafted on Rangpur lime. The soluble solids content of fruits from scions grafted on Flying Dragon was higher, but the degree of uniformity of the soluble solids values obtained from the Rangpur lime tree was higher.

ALA Promotes Sucrose Accumulation in Early Peach Fruit by Regulating SPS Activity.

5-Aminolevulinic acid (ALA), as a novel plant growth regulator, is a critical precursor for the biosynthesis of porphyrin compounds in all organisms. Many studies have reported that exogenous ALA treatment could improve fruit sweetness. However, the mechanism by which ALA promotes the increase in sugar content in fruit remains unclear. In this study, we found that ALA significantly promoted sucrose accumulation and SPS (sucrose phosphate synthase) activity in peach fruit. At 14, 28, 42, 50 and 60 days after ALA treatment, sucrose content of fruit was increased by 23%, 43%, 37%, 40% and 16%, respectively, compared with control treatment, and SPS enzyme activity was increased by 21%, 28%, 47%, 37% and 29%, respectively. Correlation analysis showed that the sucrose content of peach fruit under ALA treatment was significantly positively correlated with SPS activity. Subsequently, bioinformatics was used to identify SPS gene family members in peach fruit, and it was found that there were four members of the PpSPS gene family, distributed on chromosomes 1, 7 and 8, named PpSPS1, PpSPS2, PpSPS3 and PpSPS4, respectively. The results of qRT-PCR showed that PpSPS2 and PpSPS3 were highly expressed in response to ALA during fruit development, and the expression of PpSPS2 was positively correlated with SPS activity and sucrose accumulation in peach fruit. The results of tobacco subcellular localization showed that PpSPS2 was mainly distributed in the cytoplasm and nucleus, while PpSPS3 was mainly distributed in the nucleus. The results of this study will lay the foundation for further study on the functions of PpSPS and the regulation of sugar metabolism during the development and ripening of peach fruit by ALA.

Nutritional quality of tomato in response to different fertilization doses and conduction systems

The tomato, a rich source of essential nutrients such as vitamins A and C, potassium, and antioxidants, plays a crucial role in human nutrition, promoting health and preventing diseases. In Brazil, its production is vital, involving significant resources and labor. The correct nutritional management of the crop can improve the nutritional attributes of tomato fruits, therefore the correct use of fertilizers is of great importance due to the high need for phosphorus, nitrogen and potassium, throughout the crop cycle. Nutritional management is of great importance in tomato fields due to its high fertilizer requirements throughout the entire crop cycle. This study aimed to assess the effect of different fertilizer doses and management systems on the physicochemical characteristics of tomatoes. The experiment followed a factorial design with five fertilizer doses (A0: 0%; A1: 50%; A2: 100%; A3: 150%; A4: 200% of the recommended dose) and four conduction systems, with three replications. Productivity, lycopene content, total soluble solids (TSS), nitrogen, phosphorus, potassium, calcium and magnesium fruit contents were evaluated. The results showed that higher fertilizer doses increased lycopene levels, reaching 80 μg g-1 with 200% fertilization, while 0% provided 30 μg g-1. Total soluble solids above 4°Bx were observed at doses above 150%, regardless of planting density. Nitrogen content reached 26 mg·100 g-1f.m., favored by lower densities. Calcium was influenced by fertilizer doses, with higher concentrations at 150%. In conclusion, the application of 150% fertilizer dose improved the nutritional quality of tomatoes, and the 200% dose provided suitable levels of TSS and lycopene for processing.

Maintenance of post-harvest antioxidant quality in ‘Niagara Rosada’ grape using salicylic acid

Salicylic acid is a plant growth regulator used in grapes to maintain postharvest quality. ‘Niagara Rosada’, a table grape, although much appreciated for its flavor, has a short shelf life. We evaluated the influence of postharvest application of different doses of salicylic acid on the quality of ‘Niagara Rosada’ after harvest in an effort to control rates of berry drop and decay, as well as to maintain the quality of grape bunches during refrigerated storage. Freshly harvested bunches of ‘Niagara Rosada’ (Vitis labrusca x V. vinifera) were immersed in salicylic acid solutions at concentrations of 0.0, 0.28, 0.55, 0.83, and 1.10 g L-1, and then refrigerated (5 ± 1 °C and 95 ± 5 % RH) for 20 days. Physical and chemical analyses of grapes were performed at 5-day intervals. Salicylic acid maintained the postharvest quality of ‘Niagara Rosada’ grapes throughout storage. The lowest concentration of salicylic acid (0.28 g L-1) effectively induced the synthesis of phenolic compounds and improved the antioxidant capacities of both grapes and stems. High levels of salicylic acid (0.83 and 1.10 g L-1) resulted in an increase in anthocyanin content in fruit and enzyme activities (peroxidase and superoxide dismutase) in stems, enhancing conservation and reducing levels of decay and berry drop.

Convolutional neural networks to assess bergamot essential oil content in the field from smartphone images

The essential oil (EO) extracted from bergamot peel (Citrus bergamia, Risso et Poiteau) is appreciated in perfumery and gastronomy. Notably, 90 % of the bergamot EO production is concentrated in the Province of Reggio Calabria (Southern Italy) under a protected designation of origin (PDO). The early estimation of EO content in fruits is fundamental to help farmers in their decision at harvesting period. The application of advanced modelling techniques based on artificial intelligence and digital device technology can contribute to this goal. This study proposes a method to estimate the EO content of fruits in the field using classification and regression models based on a deep learning approach in two cultivars: cv. “Fantastico” and cv. “Femminello”. The first step was to capture images of the fruit in the Red, Green, and Blue colours (RGB) using a mid-range smartphone camera and a portable inspection chamber designed and developed for this study. The acquisition of the images was carried out in the field. The fruits were collected and transported to the laboratory, where the EO was extracted using steam hydrodistillation. Custom-built convolutional neural networks (CNN) and three transfer learning models (VGG-16, VGG-19, and Xception architectures) were trained and applied for classification (among different discrete levels of oil content) and regression (to predict the EO content). The classification results showed an accuracy of 0.795 and 0.797 on the test samples of the two cultivars separately, while the best regression model achieved a minimum mean squared error of 0.12 and 0.04 for each cultivar, respectively. The results showed the effectiveness of the approach tested and how modelling each variety independently can lead to better performance for the CNNs tested.

Molecular Characteristics and Functional Identification of a Key Alpha-Amylase-Encoding Gene AMY11 in Musa acuminata.

Alpha-amylase (AMY) plays a significant role in regulating the growth, development, and postharvest quality formation in plants. Nevertheless, little is known about the genome-wide features, expression patterns, subcellular localization, and functional regulation of AMY genes (MaAMYs) in the common starchy banana (Musa acuminata). Twelve MaAMY proteins from the banana genome database were clustered into two groups and contained a conserved catalytic domain. These MaAMYs formed collinear pairs with the AMYs of maize and rice. Three tandem gene pairs were found within the MaAMYs and are indicative of putative gene duplication events. Cis-acting elements of the MaAMY promoters were found to be involved in phytohormone, development, and stress responses. Furthermore, MaAMY02, 08, 09, and 11 were actively expressed during fruit development and ripening. Specifically, MaAMY11 showed the highest expression level at the middle and later stages of banana ripening. Subcellular localization showed that MaAMY02 and 11 were predominately found in the chloroplast, whereas MaAMY08 and 09 were primarily localized in the cytoplasm. Notably, transient attenuation of MaAMY11 expression resulted in an obvious increase in the starch content of banana fruit, while a significant decrease in starch content was confirmed through the transient overexpression of MaAMY11. Together, these results reveal new insights into the structure, evolution, and expression patterns of the MaAMY family, affirming the functional role of MaAMY11 in the starch degradation of banana fruit.

Technological aspects and requirements to raw materials for increasing the nutritional value of glaze

Glaze, giving confectionery products an aesthetically attractive appearance, provides the possibility of prolonging their shelf life. The main raw components of the glaze are sugar and fat, which determines its high caloric content. Modern trends dictate the need to create confectionery products enriched with essential nutrients found in vegetables, berries and fruits. The introduction of finely ground additives in the form of fruit and vegetable powder into the glaze formulation may entail changes in the rheological and crystallization properties of the glaze. The aim of the research is to develop technological methods of fruit and vegetable confectionery glaze production with increased content of dietary fibers and reduced amount of added sugar, as well as to establish requirements for fruit and vegetable powders as raw materials used in the production of confectionery glaze. The objects of the research were industrial samples of fruit and vegetable powders from raspberry, apple, carrot and beet, as well as samples of confectionery glaze produced in laboratory conditions. Common and special research methods were used in the work. The technological acceptability of using fruit and vegetable powders in the production of confectionery glaze according to their physical and chemical parameters has been determined. The yield stress of the glaze increased as the content of fruit and vegetable powder increased from 3 to 15% to varying degrees depending on its fat-absorbing capacity. The crystallization characteristic of the glaze changed: the solidification temperature decreased by 1-2 °C, the crystallization duration increased by 27-40% compared to the control sample. The nomenclature is substantiated and numerical values of quality criteria of fruit and vegetable powders to ensure technological properties of glaze are given. The influence of step-by-step introduction of surfactants on the value of yield stress of confectionery glazes with fruit and vegetable powders is shown. The technology of fruit and vegetable confectionery glaze with a high content of dietary fiber (9 g/100 g) and with a reduced amount of added sugar has been developed.

Chlorophyll content estimation and ripeness detection in tomato fruit based on NDVI from dual wavelength LiDAR point cloud data

Tomato (Solanum lycopersicum L.) is a climacteric fruit exhibiting the ripening pattern with change in colour from green to red. Normalized difference vegetation index (NDVI) derived from spectral-optical analysis has been previously employed in ripeness analysis of various fruits based on its strong correlation to ripening-related chlorophyll content. In this study, light detection and ranging (LiDAR) laser scanner was applied to gain 3D tomato point clouds aimed at estimating the spatially resolved chlorophyll content and ripeness class of tomato fruit. Freshly harvested tomatoes, capturing six ripeness classes (mature green, breaker, turning, pink, light red, and red) according to USDA colour standard, were analysed using a linear conveyor mounted sensor system consisting of two LiDAR units measuring position and return signal strength intensity at 660 nm and 905 nm. Fruit point clouds were pre-processed including geometric correction considering the curvature of each tomato sample, removing highest intensity areas at the specular highlighted spots, calibration of intensity values using standard black and white colour coated boards, and calibration on attenuation of the opaque samples. Particularly, for gaining the attenuation coefficient (μ), 9 opaque synthetic models with known attenuation were used. Obtained μ660 and μ905 were merged to gain NDVILiDAR. Chemically analysed chlorophyll content of tomato samples was correlated to μ660 and NDVILiDAR, whereas low correlation appeared for μ905 with a coefficient of determination (R2) of 0.58, 0.60, and 0.06, respectively. Regression models were used to estimate the total tomato chlorophyll content and the lowest root mean square error (RMSE) was found for μ660 (RMSE = 4.97 mg (100 g dry mass)−1) followed by NDVILiDAR (RMSE = 5.22 mg (100 g dry mass)−1), and μ905 (RMSE = 53.50 mg (100 g dry mass)−1). Histograms of NDVILiDAR and μ660 were extracted from each tomato point cloud and utilized to construct PLS-DA model for tomato ripening class prediction considering the spatial chlorophyll distribution. The overall accuracies for NDVILiDAR and μ660 were 70 % and 68 %, respectively, in leave-one-out cross-validation for visually defined colour classes. The LiDAR-based approach could support selective detection of ripe fruit in robots for harvesting and postharvest handling.

Effects of tea infusion on selenium uptake in grapevine

Increased selenium (Se) content in fruits can supply Se in human body, but the effects of teas on the Se uptake in fruit trees are unknown. The effects of infusions of four teas (green, black, dark, and white) on the Se uptake of grapevine were studied to promote the Se uptake in fruit trees in this study. However, only black tea infusion increased the biomass, photosynthetic pigment content, superoxide dismutase (SOD) activity, peroxidase (POD) activity, and soluble protein content of grapevine. Except for white tea infusion, other tea infusions also increased the catalase (CAT) activity of grapevine. Furthermore, the tea infusions increased the activities of adenosine triphosphate sulfurase (ATPS) and adenosine 5’-phosphosulfate reductase (APR), and decreased the activities of serine acetyltransferase (SAT) and selenocysteine methyltransferase (SMT). Only the dark and white tea infusions increased the shoot total Se content by 86.53% and 23.32%, respectively (compared with the control), and also increased the shoot inorganic Se content and shoot organic Se content. Notably, four tea infusions decreased the organic Se proportion and increased the inorganic Se proportion in grapevine. Correlation and grey relational analyses showed that the root total Se content, ATPS activity, and ARP activity were closely associated with the shoot total Se content. The principal component and cluster analyses also showed that the ATPS activity, APR activity, root total Se content, and shoot total Se content were classified into one category. These findings show that black tea infusion can promote grapevine growth, while dark and white tea infusions can promote the Se uptake in grapevine.

Characterization of zein-based films plasticized with deep eutectic solvents and their use in the preservation of harvested mango fruit

The harsh environmental impact of synthetic plastics used in packaging is driving the search for biobased alternatives. To address this urgent need, we explored the syntheses of zein films containing deep eutectic solvents (DESs). Four DESs (hydrogen bond acceptor: choline chloride (ChCl); hydrogen bond donors: citric acid (Ca), lactic acid (La), urea (Ur) and ethylene glycol (Eg)) were incorporated into zein as plasticizers, and their structural, physical, mechanical and antibacterial properties were evaluated. The results showed that the zein films plasticized with the DESs exhibited enhanced mechanical and barrier properties and hydrophilic surfaces with limited water swelling. Zein films prepared by adding DESs showed varying antibacterial effects against both Escherichia coli and Staphylococcus aureus. Among these films, the zein films plasticized with ChCl-Ca had the best mechanical, water barrier and antibacterial properties. The observation of scanning electron microscopy displayed that zein film containing ChCl-Ca had a denser microstructure compared to other plasticized films. Furthermore, we used pure zein and ChCl-Ca plasticized zein to coat mango fruit and investigated their preservation effects. The results showed that both coating treatments reduced the weight loss and delayed the declines in the peel chromaticity L*, pulp firmness and soluble solids content in mango fruit during storage comparing to control and ethanol treatment, but coating with ChCl-Ca plasticized zein had a more prominent effect in preserving mango fruit. We suggest that plasticization of zein films with ChCl-Ca is a valuable and convenient use of protein materials in mango preservation.

A Comprehensive Review on the Antioxidant and Anti-Inflammatory Bioactives of Kiwi and Its By-Products for Functional Foods and Cosmetics with Health-Promoting Properties

Kiwi’s increased popularity as a healthy fruit with several agro-food applications has increased the amount of bio-waste produced like leaf, peel, and seed by-products, usually combined to form a kiwi pomace, which increases the environmental footprint of kiwi fruit and waste management costs. The aim of the present study is to thoroughly review and outline the nutritional content and bioactive components of both kiwi fruit and its by-products, as well as the innovative approaches to obtain and valorize kiwi’s bioactives, phytochemicals, vitamins, and nutrients in several functional food products, nutraceuticals, and cosmetics applications with health-promoting properties. The antioxidant and anti-inflammatory properties and mechanisms of action of the extracted polyphenols, flavonoids, flavones, organic acids, and other bioactive components in both the fruit and in its functional products are also elucidated. Emphasis is given to those bioactive ingredients and extracts from kiwi by-products that can be valorized in various functional foods, supplements, nutraceuticals, nutricosmetics, cosmeceuticals, and cosmetics-related applications, with antioxidant and anti-inflammatory health-promoting properties. Characteristic examples with reported health benefits are the functional kiwi fruit jelly (FKJ),fermented kiwi fruit products like wine, starchy kiwi fruit flour (SKF), and kiwi-derived functional protein bars, cheese and flour, as well as several nutraceuticals and functional cosmetics with kiwi bioactives improving their antioxidant, antiaging, and photoprotective properties, collagen synthesis, skin density, hydration, elasticity, and the wound healing process, while beneficially reducing skin roughness, wrinkles, hyperpigmentation, keratinocyte death, and DNA and cell damage. The limitations and future perspectives for these kiwi bioactive-based applications are also discussed.

Ultraviolet-to-Blue Light Conversion Film Affects Both Leaf Photosynthetic Traits and Fruit Bioactive Compound Accumulation in Fragaria × ananassa

The influence of light downconversion films (red, pink and blue films) on leaf physiological features and fruit bioactive compound accumulation was studied in strawberry plants. Red, pink and blue films were able to convert light less utilised by plants into more efficient light wavebands with various possibilities depending on the film characteristics (blue film shifts UV into blue radiation; red film shifts green into red radiation, pink film shifts UV and green into blue and red radiation but to a lesser extent than red film). Indeed, by enhancing the quality of light available for photosynthesis, the utilization of these films holds the potential to improve agricultural productivity and sustainability. All of these light downconversion films resulted in higher plant fresh weight compared to a control colourless (Cnt) film, with plants grown under blue film (UV-to-blue light conversion) showing the most impressive results in terms of total leaf area (+25%), leaf thickness (+10%) and leaf mass per area (+15%). Simultaneously, during the flowering stage, plants under blue film had a higher net photosynthetic rate due to the increase in photosynthetically efficient wavelengths. Moreover, blue film resulted in the highest total phenolic (+40% and +28% than red and pink films, respectively) and flavonoid content (+54%, +84%, +70% than Cnt, red and pink films, respectively) in fruit, with specific effects on targeted phenols, i.e., quercetin, ellagic acid and its glycoside, ellagitannins, and procyanidins. In conclusion, the use of the UV-to-blue conversion light film tested herein represents an innovative solution to increase strawberry yield and promote fruit nutraceutical features, playing a pivotal role in ensuring food quality and security and sustainable agricultural practices.

Polyphenol composition and antioxidant activity of wine raw materials and pomace from hybrid grapes, aronia, and Japanese quince ia melanocarpa) and Japanese quince (Chaenomeles japonica)

Wine pomace contains high amounts of bioactive compounds, mainly polyphenols, with varying concentrations depending on multiple factors. This research aimed to determine differences in the content of polyphenols and antioxidant activity of the wine raw materials and pomace of Japanese quince (‘Rasa’), aronia (seedlings), and grape (‘Hasansky Sladky’) and between harvest years (2021, 2022), as well as between fruits and pomace. Pomace from aronia and Japanese quince was obtained after maceration for 5 and 7 days, respectively, while grape pomace was collected on the day of harvest. The polyphenol content of fruits and pomace varied significantly between harvest years. Aronia had the highest total polyphenol content in fruits (989 mg GAE 100 g-1) and pomace (1022 mg GAE 100 g-1), followed by Japanese quince (625 and 722 mg GAE 100 g-1) and grapes (390 and 481 mg GAE 100 g-1). Aronia fruits and pomace had higher antioxidant activity. Compared to the fruits, aronia pomace had less chlorogenic acid and neochlorogenic acid. Flavanols were the main polyphenols in the Japanese quince, showing lower content in the pomace when compared to fruits, except catechin content was higher. The content of anthocyanins and flavonols was higher in the rosé wine pomace than in the fruits of grapes.

The efficiency of Ca and K nitrate on the control of SERB damage in 'Thomson’ orange by modification of peel physical and chemical characteristics

One of the most severe peel physiological disorders of orange fruits is Stem End Rind Breakdown (SERB), a severe postharvest physiological disorder. We expected foliar Ca and K application to reduce orange SERB by modifying several peel biochemical and physical characteristics. Therefore, one experiment (2018–2020) was designed in complete randomized blocks in four treatments with three replicates. Experimental treatments included foliar spray of (1) K nitrate; (2) Ca nitrate; (3) Ca, and K nitrate separately, with a time interval (Ca + K; combination of treatments 1 and 2); (4) control. The effects of treatments were evaluated on several parameters underlying fruit peel quality at harvest and intensity of SERB damage after 12 wk of fruit storage at 5 ◦C and 85% RH. The results showed that K-treated fruits had higher TSS and TSS/TA than other fruits. Also, the Ca treatments (including Ca and Ca + K treatments) increased Ca content in fruit peels and significantly decreased SERB damage and weight loss by 70% and 30%, respectively. In addition, Thomson orange peel obtained from Ca-treated trees (including Ca and Ca + K treatments) displayed elevated levels of pectin than other fruits. In contrast, the peels of fruits picked from trees sprayed with Ca, especially those treated with Ca + K, exhibited lower levels of total phenolic, antioxidant, and electrolyte leakage than other fruits. This study suggests that foliar application of Ca(NO3)2 and KNO3 during the fruit growth cycle while improving the internal quality of the fruit is an effective agronomical strategy that prolongs Thomson orange shelf life.

Effects of gamma irradiation treatment on ROS accumulation and carotenoid metabolism in postharvest Cara Cara fruit (Citrus sinensis L. Osbeck) during storage

This study evaluated the effect of low-dose gamma irradiation (0.3–0.9 kGy) on carotenoid accumulation in Cara Cara fruit (Citrus sinensis L. Osbeck) during storage. Additionally, the irradiation-induced ROS (reactive oxygen species) response and transcriptional levels of carotenoid biosynthesis genes were investigated. Immediate irradiation caused a temporary decrease in most carotenoid levels; however, values recovered during storage and were even higher than those of the control, particularly at 0.6 kGy, especially for carotenoid precursors and carotenes. The upregulated expression of psy, zds and lcyb during majority of the storage period, coupled with the strengthened interaction among adjacent carotenoids, might contribute to the enhanced accumulation of carotenoids in irradiated fruit. A highly positive correlation was found among ROS content, total carotenoids, and upstream expression of zds and lcyb, suggesting that the enhanced carotenoid content in irradiated Cara Cara fruits might be regulated by zds and lcyb in response to ROS accumulation. Antioxidant enzymes of APX, SOD, and CAT levels were significantly correlated with ROS accumulation. In summary, gamma irradiation (0.6 kGy) elevated the levels of carotenoids and antioxidant enzymes, which were potentially modulated by ROS in response to irradiation stress.

Selected Physical, Mechanical and Chemical Properties of Fresh Fruit Bunches for Processing of Palm Oil

Data on engineering properties of palm fruits enable the design of machinery for optimal production of palm oil. Specific physical, chemical, and mechanical characteristics of fresh fruit bunches are examined in this study. Fresh palm fruit's selected mechanical, chemical, and physical characteristics were determined using standard formulas and equations. One hundred fresh fruit bunch samples were used to ascertain the physical characteristics of the fruit bunches. While the chemical properties were ascertained using suggested standard equations and formulae, the fresh fruit bunches were tested for their strength properties under compression when loaded under an INSTRON Universal Testing Machine. Using the Microsoft Excel program, statistical analysis was performed on the collected data. The average length, breadth, thickness, geometric mean, sphericity, surface area, true mass, true volume and true density mean for palm fruits were 3.35±0.48 cm, 1.92±0.32 cm, 2.24±0.33 cm, 2.42±0.25 cm, 0.73±0.08 cm, 18.61±3.62 cm2, 7.99±1.81 g, 7.01±1.72 cm3, 1.17±0.24 g/cm3 respectively. The average static coefficient of frictions for palm fruits were 0.46±0.13, 0.64±0.18, 0.57±0.21 and 0.59±0.22 while the average angle of reposes was 24.48±6.08, 31.62±9.14, 29.26±6.80, and 29.91±9.11 on wood, mild steel, glass and stainless-steel surface respectively. The energy at break, force at break, deformation at break, strain at break, and stress at break for the palm fruits were 6.87±0.95 J, 2.22±0.80 kN, 14.58±3.02 mm, 0.36±0.08 mm/mm and 123.46±44.31 MPa respectively. The moisture, ash, fat, crude fibre, crude protein, and carbohydrate contents (proximate composition) of the palm fruits were 22.80±0.02%, 0.52±0.01%, 46.47±0.06%, 18.66±0.01%, 2.4±0.21%, and 9.14±0.30% respectively. The sodium, potassium, calcium, magnesium, iron, phosphorus and zinc contents of the palm fruits were 58.75±0.07 ppm, 94.20±0.14 ppm, 68.45±0.64 ppm, 5.21±0.00 ppm, 1.22±0.00 ppm, 1.60±0.00 ppm and 55.70±0.28 ppm respectively. This study has provided relevant information which will help engineers to develop a more efficient palm fruit extraction machines that will in turn increase the productivity and profitability of the farmers and food processors. These measured engineering properties of palm fruits help in development of palm fruit processing machines.