Maintenance Of Fruit Quality Research Articles

Luteolin-induced activation of the phenylpropanoid metabolic pathway contributes to quality maintenance and disease resistance of sweet cherry

Redox imbalance and fungal infection are major causes for quality deterioration and postharvest decay of fruit. Therefore, it is crucial to activate intrinsic antioxidative capacity and disease responses for fruit quality maintenance. Although plant-derived flavonoids have been reported for health-promoting benefits, their roles in the maintenance of fruit quality remains largely unexplored. Here, we exogenously applied luteolin, a flavonoid substance, and further examined its efficacy in maintaining fruit quality and inhibiting fungal diseases in sweet cherry. The results showed that 100 or 200 mg/L luteolin maintained better organoleptic quality and decreased disease incidence during storage. Biochemical assays revealed that luteolin activated the phenylpropanoid metabolic pathway and improved antioxidative capacity, thereby elevating total anthocyanin and flavonoid contents. Notably, luteolin inhibited mycelial growth of fungal pathogens and reduced patulin yield by Penicillium expansum. Collectively, these results suggest that luteolin is a promising alternative for maintaining better fruit quality and ameliorating disease resistance.

Effect of chlorogenic acid on controlling kiwifruit postharvest decay caused by Diaporthe sp.

Chlorogenic acid (CGA) is a phenolic compound derived from plants that has anti-microbial activity. Effect of CGA toward Diaporthe sp. infection in kiwifruit was evaluated in the present study. Results demonstrated that fungal spore germination, germ tube elongation, and mycelial growth were all significantly inhibited by CGA. Exposure of Diaporthe sp. to CGA induced a reactive oxygen species (ROS) burst, which was mediated by an influx of calcium, resulting in mitochondrial dysfunction and apoptosis. The response of fungal cells of Diaporthe sp. to CGA included the activation of the calcium/calmodulin signaling pathway. Postharvest application of CGA induced defense-related enzyme activity in kiwifruit and inhibited Diaporthe sp. infection in a concentration dependent manner. CGA also contributed to the maintenance of fruit quality during storage. Collectively, our results suggest that CGA effectively inhibits the growth of Diaporthe sp. by inducing mitochondrial oxidative stress, which is mediated by calcium influx and by inducing defense-related enzyme activity in kiwifruit. The result of this collective effect was a significant reduction on the postharvest decay in kiwifruit.

Understanding the metabolic perturbations in Carica papaya Linn. due to different ripening practices/agents using gas chromatography-mass spectrometry based metabolomics.

The study of fruit-ripening mechanism is vital as it plays a key role in the maintenance of fruit quality. Use of various xenobiotics for quick ripening has been shown to impact the quality of fruit, which in turn affect human health. In the present study, we made an attempt to understand the metabolic perturbations in Carica papaya Linn. (papaya), which has been ripened either by the ripening practice (room temperature process as control) and/or ripening agents (calcium carbide and ethylene) using gas chromatography-mass spectrometry (GC-MS) based metabolomics. The partial least squares-discriminant analysis has revealed significant alternations in 13 metabolites mainly sugars, amino acids, fatty acids, and organic acids as well as disturbances in five metabolic pathways due to different ripening practice/agents. The individual comparison of calcium carbide with control and ethylene with control has found 13 and 11 metabolites, respectively, which are common to the PLS-DA of three ripening groups. The GC-MS-based metabolomics has been able to predict the metabolic perturbations in papaya resulting from the ripening practice/agents. The findings from the present analysis has a wide application in food quality and will help to address safety concerns.

Nutraceutical coating composition for postharvest conservation of 'Paluma' guava

This work assesses the influence of edible coating with nutraceutical properties on post-harvest conservation of guavas 'Paluma'. The experiment comprised of a completely randomized design with four replicates and three fruits per plot. Six treatments were applied combining different concentrations of agar and pomegranate seed oil (PS): T1: 1% agar and 0.1 mL/L PS oil; T2: 2% agar and 0.2 mL L-1 PS oil; T3: 3% agar and 0.3 mL L-1 PS oil; T4: 4% agar and 0.4 mL L-1 oil; T5: 5% agar and 0.5 mL L-1 oil; and T6: control (fruits without coating). After the immersion in treatment solutions, the guavas remained stored in an air-conditioned room for ten days at 10 °C and 40% RH. Fruits without coating (control) ripened faster than coated ones, so the treatments preserved fruit coloration. The treatments T4 and T5 provided the best preservation of peel color, suggesting slower ripening and maintenance of fruit quality, as their colors tended to green and opaque. The firmness of fruits without coating was decreased by 35.15% concerning the coated ones. Treatments T4 and T5 had the lowest loss of fresh mass. On the other hand, T5 showed the lowest soluble solids contents (SS)(13.46%). Titratable acidity (TA), SS/TA ratio, total sugars, and carotenoids were not affected by treatments. The edible coating with 4% of agar plus 0.4 mL L-1 of pomegranate seed oil promoted the best quality traits for the post-harvest preservation of the guavas 'Paluma'.

Avaliação pós-colheita de tangerinas ‘Dekopon’ submetidas a aplicação de cloreto de cálcio em pré-colheita

As tangerinas têm apresentado grande aumento na produção devido a adoção de diversos tratos culturais, potencializando a redução de perdas e a comercialização. No entanto, faz-se necessários estudos que possam manter a qualidade pós-colheita e incremento no campo. Portanto, objetivou-se com o presente trabalho avaliar física e quimicamente os frutos de tangerina variedade ‘Dekopon’, analisando a influência da aplicação de cloreto de cálcio em 100, 200, 300, 400% da dosagem recomendada, além do controle. As amostras dos frutos foram colhidas em pomar experimental no município de Anápolis-GO e as análises foram realizadas no laboratório da EMATER-GO. O experimento foi realizado em Delineamento Inteiramente Casualizado (DIC) composto por cinco doses de cloreto de cálcio, três repetições durante quatro semanas de avaliação (0, 7, 14 e 21 dias), respectivamente, sendo as variáveis avaliadas submetidas a análise de regressão polinomial em função das semanas. Foram avaliados: massa fresca dos frutos, coloração, sólidos solúveis, acidez titulável e textura. Os dados obtidos foram submetidos a análise de regressão por meio de um teste F no nível de probabilidade de 5%, para medir o significado do modelo proposto. Conclui-se que o uso do cloreto de cálcio, não atuou de forma positiva na manutenção pós-colheita da qualidade dos frutos, no entanto, pode-se destacar que foram observadas características desejáveis com frutos maiores e manutenção da cor para aplicações de 100 e 200% da dosagem recomendada durante 21 dias de avaliação.

Modified atmosphere using propolis in post-harvested ‘Eva’ organic apple

The objective of this study was to evaluate the efficacy of different propolis extracts in post harvesting ‘EVA’ organic apple, in order to prolong storage and fruit quality maintenance. After selection, fruits were sanitized with vinegar (6%) solution, dried in the air and immersed in propolis solution for 1 minute when it has been possible. Treatments were T1: Control without application; T2: 1.5% propolis alcoholic extract (1.5% EEP); T3: 2.5% propolis alcoholic extract (2.5% EEP); T4: 1.5% aqueous propolis extract (1.5% EAqP) and T5: 2.5% aqueous propolis extract (2.5% EAqP). Fruits were packed in rigid plastic boxes and stored in a cold room with temperature of 5 ± 1 °C and 85 ± 1% RH for 80 days. Every 10 days some traits were evaluated as fruit weight loss (%), respiratory activity (mL of CO2 kg of fruit-1 hour-1), luminosity, chroma, Hue angle, pH, soluble solids (°Brix), titratable acidity (g of malic acid 100g-1) and reducing and non-reducing sugars. The experimental design was completely randomized in a factorial scheme and data were submitted to F test (p <0.05) and significant interactions were deployed via regression analysis. The application of propolis extract (aqueous and alcoholic) in ‘Eva’ organic apple post-harvest does not prolong refrigerated storage (5 ± 1ºC and 85 ± 1% RH) and does not influence in fruit quality conservation.

Interaction between nitric oxide and storage temperature on sphingolipid metabolism of postharvest peach fruit

Both nitric oxide (NO) and cold storage have positive effects on the maintenance of fruit quality during storage. However, the roles of NO and storage temperatures in regulating the responses of sphingolipids metabolism to chilling injury of peach fruit during storage remain unknown. Peaches were treated by immersion in distilled water and 15 μmol L−1 NO solution, then stored at 25 °C and 0 °C, respectively. The effects of NO-treatment and storage temperature on the activities of enzymes in sphingolipid metabolism and the contents of sphingolipids in peach fruits were studied. NO maintained higher activities of acid phosphatase (AP) and alkaline phosphatase (ALP) in peach fruits at 25 °C, but promoted the decrease in the activities of AP and ALP at 0 °C, suggesting the regulation by NO on AP and ALP could be modulated by temperature. Compared with the storage at 25 °C, cold storage at 0 °C decreased the activities of phospholipase A (PLA), alkaline phosphatase (ALP), 3-ketodihydrosphingosine reductase (KDSR), sphingosine kinase (SPHK), ceramide synthase (CERS), ceramide kinase (CERK), and the contents of sphingosine (SPH), ceramide (CER), sphingosine-1-phosphate (S1P), ceramide-1-phosphate (C1P), sphingomyelin (SM), and increased the activities of phospholipase C (PLC), phospholipase D (PLD), sphingomyelin synthase (SMS). NO significantly increased the contents of sphingolipid metabolites, and the activities of PLA, KDSR, SPHK, CERS, CERK, but decreased the activities of PLC, PLD, SMS of peaches. The results suggested that NO could maintain sphingolipid metabolism to relieve the response of the postharvest fruit to low temperature.

Effect of enriched O2 and CO2 atmospheres on the overall quality and the bioactive potential of fresh blackberries

Abstract This work aimed to study the effects of the refrigerated storage of blackberries in high O2 and high CO2 atmospheres (70 kPa O2 + 20 kPa CO2 and 90 kPa O2 + 10 kPa CO2) on the quality and bioactive potential. Fruit stored in 90 kPa O2 + 10 kPa CO2 controlled the microorganism growth better than in 70 kPa O2 + 20 kPa CO2 until the end of storage (18 and 15 d, respectively). Both atmospheres were better than air that only controlled microorganisms for 8 d. Vitamin C retention of samples stored in air was close to 40 % at 8 d, being equal to those registered for the enriched O2 and CO2 atmospheres samples, but in the double of time. The retention of the total phenolic compounds of blackberries treated with 70 kPa O2 + 20 kPa CO2 experienced a transient increase (around 10 %) on 1 d and then decreased with time, being 90 % at the end of storage (15 d). The antioxidant capacity of fruit stored under air and O2- and CO2-enriched atmospheres generally accompanied the evolution of phytochemicals during storage. The refrigerated storage of blackberries in 70 kPa O2 + 20 kPa CO2 is recommended based on longer maintenance of fruit quality (compared to fruit stored in air), synthesis of phenolic compounds and the increase in the antioxidant capacity, which offers fruit with enhanced bioactivity. The changes in the blackberry quality attributes and in the antioxidant capacity were better fitted with first order kinetic, and the changes in the phenolic compounds were adequately fitted with a consecutive reaction mechanism kinetic model. Meanwhile, the microbiological evolution was satisfactorily evaluated by the Baranyi-Roberts model.

Integration of UV irradiation and chitosan coating: A powerful treatment for maintaining the postharvest quality of sweet cherry fruit

Sweet cherry is a non-climacteric fruit consumed more as fresh for its essential nutrients and phytochemical compounds. In this study, the single and combined effects of UV-B (21.6 kj/m2), UV-C (21.6 kj/m2) radiation, and chitosan (CS) coating 1 % treatments on fruit quality of sweet cherry were studied during 28 d at 4 °C. Sweet cherry fruit were evaluated for weight loss, firmness, total titratable acidity (TTA), pH, total soluble solids (TSS), ascorbic acid (AA), total anthocyanin content (TAC), antioxidant (AOX) capacity and total phenol compounds (TPC) every 7d. Compared with control, fruit quality was better maintained in UV/CS treated fruit. The UV/CS treatments significantly inhibited the decrease in the firmness, TAC, and AOX capacity, and the increased rate of weight loss and TSS in the sweet cherry fruit. Although both UV lights were effective in the maintenance of fruit quality, sweet cherries treated with UV-C showed higher TPC accumulation and related AOX capacity compared to UV-B treatment. Overall, the integration of UV lights (UV-B and UV-C) with CS was the best treatment that could strongly inhibit the increase in the weight loss and TSS and achieved the highest firmness, AA, TAC, AOX capacity and TPC. Our results indicate that the integrated management is a potentially effective method for preventing undesirable post-harvest changes and extending the shelf-life of sweet cherry fruit.

Impact of elevated O2 and CO2 atmospheres on chemical attributes and quality of strawberry (Fragaria × ananassa Duch.) during storage

Modified atmosphere has widely been evident to contribute to fruit quality maintenance, however the correlation among these quality traits was less known. To explore main factors of elevated atmosphere and reduce the detection indexes, we exposed strawberry to either high O2 (80% O2 + 20% N2) or CO2 (20% CO2 + 20% O2 + 60% N2) atmosphere and compared quality characteristics. It was demonstrated that both atmospheres well maintained the fruit firmness, alleviated weight loss and decay rate. Elevated O2 maintained the polyphenolic contents and cell integrity by significantly decreasing superoxide and hydrogen peroxide levels. PCA analysis implied that HO treatment mainly affected oxygen metabolism while HCO affected carbon metabolism more. Significantly positive correlation was observed between weight loss, anthocyanin content and decay rate in elevated O2 and control groups. This study provided new insights into correlation and difference between impact of elevated O2 and CO2 to postharvest preservation.

Regulation of Hydrogen Sulfide Metabolism by Nitric Oxide Inhibitors and the Quality of Peaches during Cold Storage.

Both nitric oxide (NO) and hydrogen sulfide (H2S) have been shown to have positive effects on the maintenance of fruit quality during storage; however, the mechanisms by which NO regulates the endogenous H2S metabolism remain unknown. In this experiment, peaches were immersed in solutions of NO, potassium 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO, as an NO scavenger), N-nitro-l-arginine methyl ester (l-NAME, as an inhibitor of nitric oxide synthase (NOS)-like activity), and sodium tungstate (as an inhibitor of nitrate reductase), and the resulting changes in the H2S metabolism of peaches were studied. The results showed that exogenous NO reduced the contents of endogenous H2S, Cys, and sulfite; decreased the activities of l-/d-cysteine desulfhydrase (l-/d-CD), O-acetylserine (thiol)lyase (OAS-TL), and sulfite reductase (SiR); and increased the activity of β-cyanoalanine synthase (β-CAS). Both c-PTIO and sodium tungstate had similar roles in increasing the H2S content by sustaining the activities of l-/d-CDs, OAS-TL, and SiR. l-NAME increased the H2S content, mainly by maintaining the d-CD activity. The results suggest that NO, c-PTIO, l-NAME, and sodium tungstate differently regulate the H2S metabolism of peaches during storage.

Extending the Postharvest Quality of Peach Fruits by Salicylic Acid and MAP Treatments

Postharvest salicylic acid (SA) treatments can decrease the fungal decay of horticultural crops by affecting the ethylene biosynthesis and inducing the systemic resistance during cold storage. In the present study, effects of SA and modified atmosphere packages (MAP) on the postharvest quality maintenance of fruits of peach cv ‘J. H. Hale’ were investigated. After harvest at commercial maturity, half lot of each of the fruits was subjected to 1 mM SA for 5 min and was packed with or without MAP. The remaining lot was not subjected to SA but was also stored with or without MAP. All the fruits were stored at 1°C and 90% relative humidity for 60 d. Weight loss, color of flesh and skin, firmness, total soluble solid, titratable acidity, total phenolic and total antioxidant analyses were performed with 15 d intervals to compare the effectiveness of treatments. SA treatment had positive influences on the of postharvest quality maintenance of the fruits. In p P articular ly , the combined use of SA and MAP was more effective than their individual use i o n maintaining the firmness of the fruits , delaying the biochemical changes in the with flesh and alterations in the skin color than their single use .

Effect of Cassava Starch Coating on the Quality and Shelf Life of Prickly Pear in Refrigerated Storage

In Brazil, the prickly pear has been gaining more and more attention, mainly due to its nutritional health promotion benefits. However, its postharvest conservation is still incipient The aim of this study was to evaluate the use of cassava starch in different concentrations in relation to quality preservation and postharvest shelf life prolongation of prickly pear stored at 10 °C and relative humidity of 95%. Fruit were harvested at maturation stage III, in plants with 8 years of age, in the municipality of Janaúba - MG. Then they were selected, sanitized and immersed in sulutions of cassava starch at 0; 1; 2 and 3% for 1 minute and stored at 10 ± 1 ◦C and relative humidity of 95 ± 5%, for 25 days, and evaluated every five days. The designed trial consisted of a completely randomized trial, in a 4x6 factorial scheme: four concentrations of cassava starch and six periods of evaluations (0, 5, 10, 15, 20 and 25 days), with four replications. Fruit were evaluated for physical, chemical and nutritional characteristics. During storage were observed weight loss, firmness loss, chlorophyll degradation, acidity reduction and ascorbic acid, with increase of soluble solids, total sugars and carotenoids in fruit. The higher the cassava starch concentration, the greater the maintenance of fruit quality. The 3% cassava starch coating was the most efficient at delaying the weight loss, decay, softening and wilting in the fruits, the main characteristics that affect the quality of prickly pear. However, this concentration presented, as an inconvenience, coating peeling at the end of storage.

Effect of foliar application with sodium selenate on selenium biofortification and fruit quality maintenance of 'Starking Delicious' apple during storage.

Selenium (Se) is an essential micronutrient due to its anticarsinogenic properties and positive influence on human immune system. Fortification of some fruits based on their rates of consumption and availability all year round appears to be an effective way to supplement Se in the human diet. In this study the possibility of augmenting Se content in 'Starking Delicious' apple fruit during two growing seasons was investigated. In 2016, the impact of 0, 0.5, 1 and 1.5mg Se L-1 by foliar application on Se accumulation and fruit ripening as well as quality attributes was investigated. In 2017, the effects of 1.5mg Se L-1 foliar application on fruit Se content and changes in the antioxidant system and storability were studied with a 30-day interval during 6months storage at 0 ± 1°C. Foliar application of Se significantly increased both leaf and fruit Se concentration. The increase in Se content enhanced the flesh firmness, titrable acidity, and soluble solid content of the fruit. The activities of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) were markedly amplified by Se treatments as compared to the control, resulting in lower superoxide anion radical (O2 -• ) and hydrogen peroxide (H2 O2 ) contents, correspondingly higher membrane integrity as revealed by lower ion leakage and malondialdehyde accumulation and the fruit with lower water core. Application of Se was efficient in increasing fruit Se content and nutraceutical properties, retarding the flesh firmness reduction, and postponing fruit ripening resulting from lower ethylene biosynthesis rate, thereby positively affecting apple fruit quality and storability. © 2019 Society of Chemical Industry.

Use of edible coatings based on hydroxypropyl methylcellulose and beeswax in the conservation of red guava ‘Pedro Sato’

Guavas are tropical climacteric fruit with a short postharvest shelf life at room temperature. This study aims to extend the shelf life of red guavas ‘Pedro Sato’ using edible coatings of hydroxypropyl methylcellulose (HPMC) and beeswax (BW) at concentrations of 10%, 20%, and 40% (dry basis). Coated and uncoated guavas were stored for 8 days at 21 °C and assessed every 2 days. The HPMC + BW produced a modified atmosphere around the fruit, delaying ripening process. The coatings reduced loss of mass, maintained green color, and increased firmness compared to the control fruit. The uncoated fruit had 6 days of shelf life. The treatment with HPMC + 20% BW provided the best maintenance of fruit quality. On the eighth day, fruit with this coating showed the same physicochemical characteristics of control fruit in the second day of storage, which represents a gain of 6 days in the shelf life of guavas ‘Pedro Sato’.

A main effects meta principal components analysis of netting effects on fruit: using apple as a model crop

To differentiate effects of netting and attribute them to crop, cultivar, planting density, climate, net type and colour, ca. 200 publications were scanned originally. Apple was chosen as a model crop due to the majority of reports, wide variation with many varieties and growing locations worldwide in the Northern and Southern hemisphere, but the results may be useful for other fruiting plants. After meeting strict selection criteria, a meta-analysis of 26 internationally published peer-reviewed articles was based on seven varieties and seventeen locations with a diverse range of climates. A novel Main Effects Meta Principal Components Analysis (ME Meta-PCA) was developed and provided unexpectedly uniform results: Location (climate), planting density and hail net (type and colour) had negligible impacts. Fruit (red) colour, most adversely affected by netting, correlated with TSS viz fruit sweetness, as often postulated in consumer studies, followed, to a smaller extent, by sugar/TSS, fruit firmness and acidity but small increase in fruit mass—i.e. maintenance of fruit quality under netting over all seven varieties (Braeburn, Gala, Elstar, Jonagold, Pinova and Fuji) examined and locations worldwide. While Jonagold and the early ripening Gala appeared suitable, unaffected and stable in the netting effects in the ME Meta-PCA, Pinova was the least suitable for cultivation under netting. Interestingly, late ripening cultivars (Braeburn and Cripps Pink) were both positively influenced by desired earlier ripening under netting. These effects on fruit quality are discussed with respect to shade adaptation under netting and countermeasures such as easy colouring mutants or reflective mulches.

Transcript analyses of ethylene pathway genes during ripening of Chinese jujube fruit

The fruit of Chinese jujube (Ziziphus jujuba Mill.) is immensely popular worldwide, while its fleshy fruit has a very short shelf life and suffers serious postharvest damage. The fruit has been controversially classified as non-climacteric, though the mechanisms underlying its ripening behavior, particularly the role of ethylene, have remained unclear. In this study, low and stable ethylene production was detected during ripening of Z. jujuba ‘Dongzao’ fruit, with production increasing at the full maturity stage. To determine potential ripening behavior, the fruit of five cultivars were harvested at the white mature stage, and all exhibited a first decreasing and then moderately increasing respiration rate without concomitant climacteric-like ethylene production during shelf storage. Treatment with 1.0 μL L−1 1-methylcyclopropene (1-MCP) inhibited respiration and ethylene production in white mature fruit, though the effects of 100 μL L−1 exogenous ethylene were not significant. The transcript levels of genes involved in ethylene biosynthesis, perception, and signal transduction were not elevated during fruit-ripening onset but substantially increased at the full-red ripening stage. Moreover, expression of genes controlling ethylene biosynthesis and perception mainly occurred in an auto-inhibited System-1-like manner, but signaling pathway genes were minimally affected by exogenous ethylene or 1-MCP. These results show that the ripening of Chinese jujube is non-climacteric. The basal level of ethylene likely plays a minor role in ripening regulation but is necessary to maintain normal ripening. This study elucidates the effects of ethylene on jujube fruit ripening, characterizing the ripening of this fruit as non-climacteric, and also provides strategies for the improvement and maintenance of fruit quality and the extension of shelf life during postharvest storage.

Potential of UVC germicidal irradiation in suppressing crown rot disease, retaining postharvest quality and antioxidant capacity of Musa AAA "Berangan" during fruit ripening.

Crown rot caused by fungal pathogen is the most prevalent postharvest disease in banana fruit that results significant economic losses during transportation, storage, and ripening period. Antifungal effects of ultraviolet C (UVC) irradiation at doses varied from 0.01 to 0.30 kJ m−2 were investigated in controlling postharvest crown rot disease, maintenance of fruit quality, and the effects on antioxidant capacity of Berangan banana fruit during ripening days at 25 ± 2°C and 85% RH. Fruits irradiated with 0.30 kJ m−2 exhibited the highest (i.e., 62.51%) reduction in disease severity. However, the application of UVC at all doses caused significant browning damages on fruit peel except the dose of 0.01 kJ m−2. This dose synergistically reduced 46.25% development of postharvest crown and did not give adverse effects on respiration rate, ethylene production, weight loss, firmness, color changes, soluble solids concentration, titratable acidity, and pH in banana as compared to the other treatments and control. Meanwhile, the dose also enhanced a significant higher level of total phenolic content, FRAP, and DPPH values than in control fruits indicating the beneficial impact of UVC in fruit nutritional quality. The results of scanning electron micrographs confirmed that UVC irradiation retarded the losses of wall compartments, thereby maintained the cell wall integrity in the crown tissue of banana fruit. The results suggest that using 0.01 kJ m−2 UVC irradiation dose as postharvest physical treatment, the crown rot disease has potential to be controlled effectively together with maintaining quality and antioxidant of banana fruit.

Changes in quality and defense resistance of kiwifruit in response to nitric oxide treatment during storage at room temperature

The effects of nitric oxide (NO) treatment on quality and disease resistance of kiwifruit (Actinidia deliciosa) cv. ‘Bruno’ were investigated after the fruits were immersed in 0.2mM sodium nitroprusside or water (as control) for 10min and then stored at room temperature. NO treatment reduced diseases incidence; delayed the increase in soluble solid content and the loss of vitamin C (Vc); increased the activities phenylalanine ammonialyase (PAL), peroxidase (POD), and β-1,3-glucanase, with accompanying up-regulation of PAL, POD and chitinase (CHT) expression; and elevated the level of total phenolics, flavonoids, hydroxyproline-rich glycoprotein, and lignin during storage. Thus, NO treatment was beneficial to the maintenance of fruit quality and improvement of disease resistance of kiwifruit during storage.

EXTENDED COLD STORAGE OF WINTER PEARS BY MODIFIED ATMOSPHERE PACKAGING

ABSTRACT The aim of this work was to evaluate the effect of passive modified atmosphere packaging (MAP) on the maintenance of fruit quality during the extended storage of ‘Rocha’ and ‘Packham’s Triumph’ pears. Fruit were packed in linear low density polyethylene (100 mm), with 6% BIF 1500 additive placed into perforated plastic boxes and kept at 0 ± 1 °C and 90 ± 5% RH for up to 180 days. MAP reduced weight loss by 14.8% for ‘Rocha’ and 11.5% for ‘Packham’s’ pears after 180 days in cold storage and retained the green color of the skin, which means that the yellowing visual perception was delayed in 60 and 90 days for ‘Rocha’ and ‘Packham’s’ pears, respectively. A strong softening was observed for ‘Packham’s’ pears after being kept for 150 days at 0° C followed by 5 days at room temperature, which did not limit the storage of both pear cultivars under modified atmosphere packaging. MAP created by linear low density polyethylene (100 mm), with 6% BIF 1500 additive extended in 30 days the cold storage for ‘Rocha’ and 60 days for ‘Packham’s’ pears.