Berry Decay Research Articles

Metabolic Profiling and Molecular Mechanisms Underlying Melatonin-Induced Secondary Metabolism of Postharvest Goji Berry (Lycium barbarum L.).

Postharvest decay of goji berries, mainly caused by Alternaria alternata, results in significant economic losses. To investigate the effects of melatonin (MLT) on resistance to Alternaria rot in goji berries, the fruits were immersed in the MLT solutions with varying concentrations (0, 25, 50, and 75 μmol L-1) and then inoculated with A. alternata. The results showed that the fruits treated with 50 μmol L-1 MLT exhibited the lowest disease incidence and least lesion diameter. Meanwhile, endogenous MLT in the fruits treated with 50 μmol L-1 MLT showed higher levels than in the control fruits during storage at 4 ± 0.5 °C. Further, the enzymatic activities and expressions of genes encoding peroxidase, phenylalanine ammonia-lyase, cinnamate 4-hydroxylase, 4-coumarate-CoA ligase, chalcone synthase, chalcone isomerase, and cinnamyl alcohol dehydrogenase were induced in the treated fruit during storage. UPLC-ESI-MS/MS revealed that secondary metabolites in the fruits on day 0, in order of highest to lowest levels, were rutin, p-coumaric acid, chlorogenic acid, ferulic acid, caffeic acid, naringenin, quercetin, kaempferol, and protocatechuic acid. MLT-treated fruits exhibited higher levels of secondary metabolites than the control. In conclusion, MLT treatment contributed to controlling the postharvest decay of goji fruit during storage by boosting endogenous MLT levels, thus activating the antioxidant system and secondary metabolism.

Trichoderma asperelloides 5R and Bacillus licheniformis TL-171 reduce epiphytic colonization and post-harvest berry decay due to Cladosporium sp. and improve the shelf life of grapes

Trichoderma asperelloides 5R and Bacillus licheniformis TL-171 reduce epiphytic colonization and post-harvest berry decay due to Cladosporium sp. and improve the shelf life of grapes

Influence of Aloe vera and salicylic acid on storage life of grapes cv. Flame Seedless

Salicylic acid (1, 2, and 3 mM) in combination with aloe vera as postharvest dipping treatments were applied to grapes cv. ‘Flame Seedless’ to investigate their effects on the storage life and fruit quality parameters. The fruits were packed in low-density polyethene packaging with grape guards and placed further in corrugated fibre board boxes and stored at 0–2 oC with 90–95% RH. The investigation was carried out at 15, 30, 45, 60 and 75 days of storage for quality related parameters. Salicylic acid @ 2 mM combined with 50% aloe vera significantly reduced the physiological loss in weight, berry decay, berry shattering, membrane electrolyte leakage and improved the organoleptic quality. The treatments slowed down the degradation of anthocyanin levels in the berries. The extent of browning on rachis of the clusters treated with salicylic acid was slowed down with the progression of the storage period, in comparison with the control. The treatment of salicylic acid + aloe vera @ 2 mM imposed on grape bunches exhibited better consumer acceptability and enhanced fruit quality attributes in storage, enabling them to store up to 60 days under given conditions.

Preharvest salicylic acid treatments improve phenolic compounds and biogenic amines in ‘Niagara Rosada’ table grape

The ‘Niagara Rosada’ (Vitis labrusca) grape is widely consumed for its nutritional qualities and flavor, in addition to presenting a great diversity of phytochemical compounds, mainly polyphenols. ‘Niagara Rosada’ has a limited shelf life, especially when kept at room temperature, a common form used by markets in Brazil. Salicylic acid (SA) is a low-cost alternative postharvest technique, due to its accessibility (low cost) and potential to mitigate postharvest losses, in addition to maintaining quality. Exogenous application of salicylic acid in the pre-harvest period was studied to improve the postharvest quality of ‘Niagara Rosada’ grapes with the aim of increasing its shelf life. SA was applied in different doses, in two stages during the pre-harvest, in the season of berry growth and during veraison. The results show that 1 and 2 mmol L−1 were efficient in reducing the incidence of berry drop and decay of berries. Treatments with SA provided an increase in phenolic compounds. Among the phenolic acids, there was an increase in chlorogenic acid and gallic acid, related to antifungal action. Regarding polyphenols, rutin, cyanidin-3,5-diglucoside and 3-O-glycosidic delphinidin were the major compounds found in all treatments. Salicylic acid induced an increase in serotonin and melatonin content, as well as in the aminoacids (tryptophan and 5-hydroxytryptophan). During the storage, there was a decrease in histamine and dopamine levels. These alterations may be used as a tool to induce fruit resistance during storage, leading to an increase of crop yields. Thus, exogenous treatment using 1 and 2 mmol L−1 SA increases postharvest life, improves biochemical quality of the musts and induces increased antioxidant compounds.

Effect of some Pre-Harvest Treatments on Quality of ʺCrimson Seedlessʺ Grapes During Cold Storage and Shelf Life

This work was carried out during two successive seasons (2017 and 2018) to examine the response of ʺCrimson Seedlessʺ grapes to some pre-harvest treatments i.e. jasmonic acid (JA) at (4 and 8) mM/L and grapefruit seed extract (GSE) at (0.5 and 1) mM/L on some berries quality parameters under cold storage and shelf-life conditions. Vines were sprayed in two application times at (25th and 30th August) during 2017 and 2018, respectively. The non-ionic surfactant Tween-20 at 0.05% (v/v) was added to all treatments to reduce the surface tension and increase the contact angle of sprayed droplets. Results showed that both jasmonic acid and grapefruit seed extract treatments at different concentrations were significantly effective in reducing weight loss, berry decay, berry shatter, and total loss in cluster weight percentages during the cold storage period and shelf life as compared to the control. Also, the previous treatments significantly increased berry firmness, soluble solid content (SSC%), SSC/acid ratio, and total anthocyanin contents, where it was caused a significant decrease in total acidity percentage during the cold storage period and shelf life in comparison with control. Furthermore, the lowest values of weight loss, berry shatter, berry decay and total loss in cluster weight were founded by JA at 8 mM and GSE at 1 mM at the end of shelf life in comparison with other treatments. It could be concluded that JA at 8 mM and GSE at 1 mM as preharvest treatments are applicable for improving the storability of ʺCrimson Seedlessʺ grapes and maintaining their quality during cold storage and shelf life.

Melatonin may increase disease resistance and flavonoid biosynthesis through effects on DNA methylation and gene expression in grape berries

BackgroundMelatonin can regulate plant growth, development and biotic responses by causing global changes in gene expression; however, the melatonin-induced changes in gene expression via the modification of DNA methylation remain unclear in plants.ResultsA total of 1,169,852 and 1,008,894 methylated cytosines (mCs) were identified in the control and melatonin-treated grape berries, respectively, and mCs occurred primarily at CG sites, followed by CHG sites and CHH sites. Compared to the control, melatonin treatment broadly decreased methylation levels at CHG and particularly CHH sites in various gene regions. Melatonin treatment generated a total of 25,125 differentially methylated regions (DMRs), which included 6517 DMR-associated genes. RNA-Seq demonstrated that 2479 genes were upregulated, and 1072 genes were repressed by melatonin treatment. The evaluation of the interconnection of the DNA methylome and transcriptome identified 144 genes showing a negative correlation between promoter methylation and gene expression, which were primarily related to biotic stress responses and flavonoid biosynthesis. Additionally, the application of 5́-azacytidine and melatonin led to similar effects on mycelial growth of B. cinerea, berry decay rate and flavonoid biosynthesis. Moreover, EDS1 was used to show that melatonin increased gene expression by decreasing promoter methylation levels.ConclusionOur results demonstrated that melatonin broadly decreased DNA methylation and altered gene expression in grape berries. We propose that melatonin increases disease resistance and flavonoid biosynthesis by decreasing the methylation levels of the promoters of the genes involved.

Berry Set and Quality Response of Soilless Grown ‘Prima’ Grapes to Foliar and Inflorescence Pulverization of Various Substances Under Glasshouse Condition

Biotic and abiotic stress factors reduce the yield of major crops and pressurize the agricultural production worldwide. Recently increased climate change events forced the growers to employ protected cultivation techniques which favor pests and disease incidences. Sustainable methods to mitigate the plant stresses and cope with the pathogens possess great significant to sustain economic productivity. This study was designed to investigate effect of commonly used chemicals (triadimenol and deltamethrin), plant growth activator (micronized calcite), zinc nutrition, and beneficial bacteria (Bacillus subtilis) at two growth stages (full bloom and berry set) on beery set and quality of table grape cv ‘Prima’. After the first application at full bloom, neither of the treatments resulted in visible damages on flowers. Micronized calcite, Zn and B. subtilis markedly improved the berry set. Zn and B. subtilis also enhanced subsequent berry development and cluster size, reduced the berry decay rate. Finally, these treatments increased the grape yield and therefore could be recommended to practice as environment friendly and sustainable strategies under protected cultivation techniques.

Postharvest evaluation of cold-hardy table-grape breeding lines

The University of Minnesota grape breeding program has evaluated a small number of cold-hardy cultivars and advanced selections for postharvest storage traits. This is the first experiment for comparing advanced selections to table-grape cultivars for these traits. Nine genotypes were evaluated for cluster weight and fruit chemistry at harvest. Three clusters per genotype were packed in ventilated polyethylene bags and arranged in carton boxes. Paper pads and SO(2) pads were placed on top of the bunches in each carton. The cartons were stored at 2.2°C for 2, 4, 6, and 8 weeks. Clusters were destructively sampled at each storage time point and evaluated for change in fruit weight, berry splitting, berry decay, juice chemistry, and an overall rating of acceptability. An advanced selection, ‘MN1296’, was the top-performing seedless cultivar for overall acceptability for postharvest traits, but has berries that tend to shatter. ‘Louise Swenson’, ‘Swenson Red’, and ‘MN1296’ were rated as the best-performing lines for stem dehydration, in descending order. ‘Swenson Red’ is the largest-fruited Elmer Swenson/UMN cultivar, but has limited commercial planting because of its seeded berries; ‘Swenson Red’ also had no shattering after storage. Berry splitting was worst in ‘Louise Swenson,’ a seeded white grape with multiple uses including wine. ‘Jupiter’ had severe rachis browning after 8 weeks, but little at 2, 4, or 6 weeks, whereas ‘Vanessa’ and ‘MN1369’ both suffered from decay. ‘Jupiter’ and ‘Vanessa’ had the largest clusters, but can be grown in Minnesota with only marginal success using the J-vine training system. Additional research on bud survival and consumer preference will be needed to determine whether any of the advanced selections are suitable for cultivar release.

Pre-harvest Micronized Calcium and Postharvest UV-C Treatments Extend the Quality of ‘Crimson Seedless’ (Vitis vinifera L.) Grapes

Certain postharvest disorders such as rachis desiccation, weight loss, accelerated softening and biochemical changes limit the postharvest life of table grapes. The present study was conducted to evaluate the effect of pre-harvest micronized calcium pulverizations, postharvest UV-C treatment and their combined applications on extending postharvest quality of table grapes cv ‘Crimson Seedless’. Pre-harvest micronized calcium pulverization was performed to improve rachis greenness and berry resistance while postharvest UV-C was aimed to induce physiological resistance and delay senescence in grape berries. Ca treatments significantly increased chlorophyll concentrations of rachis while Ca plus UV-C was the best treatment to maintain rachis chlorophyll concentration. UV-C with or without pre-harvest Ca treatment effectively delayed the weight loss during the storage. Ca delayed the increase of SSC during the storage. All the treatments, particularly postharvest UV-C, significantly delayed the berry senescence by delaying the decrease in acidity. UV-C with or without Ca, with the lowest values, significantly retarded the changes in phenols and decreased the berry decay. Ca plus UV-C treatment also effectively maintained the skin rupture force during the storage. Overall, pre-harvest micronized Ca pulverizations plus postharvest UV-C treatment can be recommended to extent the quality of table grapes cv. ‘Crimson Seedless’ up to 120 days at cold storage.

Comparison of the change in quality indices during distribution period by import season in three grape cultivars

As a result of analyzing the quality of imported grapes during the 2018 season, the hardness of the grape berry was found to be 10 N or less in total. In the case of Chilean grapes, the soluble solids tended to be lower as imports and distribution periods were delayed. The berry weight was the largest at 14.4 - 14.8 g for the 'Red Globe', 7.1 - 7.4 g for the 'Thompson Seedless' and 6.0 - 7.0 g for the 'Crimson Seedless'. The 'Crimson Seedless' grapes imported from Chile, which had a high berry shatter rate, had a shorter pedicel length, pad width and brush length than that of the other 2 varieties. Regardless of the grape varieties, the weight loss during the distribution at room temperature ( $25^{\circ}C$ ) increased rapidly as the import season was delayed. Additionally, it was found that the later the distribution seasons, a higher stem browning index was observed regardless of the variety. The 'Thompson Seedless' was revealed to be more susceptible to browning than that of the other varieties. The shrinkage of the stem and the pedicel browning progressed within a short time during shelf-life as the distribution time was delayed. The incidence of berry decay of the imported grapes tended to increase with the progression of the distribution period. In the fruits distributed on April, except for the 'Crimson Seedless', the grapes were rapidly corrupted in the second half of the distribution. The 'Red Globe' grapes completely lost marketability due to a berry decay of 26.1% and 69.9% at 9 and 12 days after shelf-life, respectively.

Effect of gaseous chlorine dioxide (ClO2 ) with different concentrations and numbers of treatments on controlling berry decay and rachis browning of table grape

Chlorine dioxide (ClO2) gas was used to control berry decay and rachis browning of table grape due to its antimicrobial and anti-browning properties. It was proposed that if ClO2 gas is fully absorbed by the fruit, the maximum total ClO2 dose can be calculated based on the maximum allowable residual concentration. To avoid possible bleaching effects on grape peel from high concentrations of ClO2, the total amount of ClO2 gas needs to be injected into the packages in many small doses at specific time intervals over the course of the 90-day storage period. Spoilage microorganism counts, decay rate, electrolyte leakage, rachis browning and residual ClO2 in berry were investigated. The results showed that ClO2 treatment could significantly reduce berry decay and rachis browning (p ≤ .05) compared to the control. Grape treated with 1.0 mg L−1 ClO2 6 times at 15-day intervals maintained better fruit quality without any risks from the residual ClO2. Practical applications The present research found that ClO2 treatment is useful for improving the microbial safety of grapes and reducing berry decay and rachis browning during storage, and low doses of ClO2 spread over many treatment can yield better results.

Biocontrol of gray mold in grapes with the yeast Hanseniaspora uvarum alone and in combination with salicylic acid or sodium bicarbonate

The yeast Hanseniaspora uvarum alone or in combination with salicylic acid or sodium bicarbonate was investigated for control of gray mold, postharvest quality and antioxidant enzymes of grapes. The results indicated that the treatment of H. uvarum suspension of 1×108CFUmL−1 combined with either 2mmolL−1 SA or 2% SBC resulted in a remarkably improved control of Botrytis cinerea infections on grapes. Disease incidence and lesion diameter in treated fruit by H. uvarum alone or combined with SA or SBC were significantly lower than those of the control fruit (P<0.05) at 25°C, RH 90–95%. Integration of H. uvarum with SA and with SBC both significantly reduced the browning index, the decay incidence, weight loss while maintained the fruit appearance, firmness, total soluble solids (TSS) and titratable acidity (TA) of the grapes (P<0.05) at 2±1°C, RH 90–95%. Furthermore, the combination of yeast and aforementioned chemicals led to increases of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), phenylalanine ammonia lyase (PAL), ascorbate peroxidase (APX) and polyphenoloxidase (PPO) activities. Enhanced control by SA or SBC could be due to either induced resistance or direct effects of these chemicals on Botrytis. The proper combination of H. uvarum and chemical reagent can thus provide an effective strategy to reduce postharvest decay of grape berries.

HEAT TRANSFER AND EXTERNAL QUALITY ATTRIBUTES OF 'REGAL SEEDLESS' TABLE GRAPES INSIDE MULTI LAYERED PACKAGING DURING POSTHARVEST COOLING AND STORAGE

Postharvest packaging of table grapes is characterized by multi-layer packaging comprising of the carton box, the inner liner film, the individual bunch carry-bag and the SO2 sheet. This multi-layered packaging is required to allow sufficient airflow to efficiently cool packed grapes in order to preserve quality. Total pressure drop and cooling rates of different table grape packaging systems were measured and the percentage contributions of each package component and the fruit bulk were determined. Also, the effects of different carton liners on the cooling rate and external quality attributes of table grapes were investigated. Fruit quality attributes measured included stem dehydration and browning, SO2 injury and decay. On average the liner films contributed significantly higher to total pressure drop (61.04±15.91 %) than other components of the package combinations. Compared with the cooling of bulk grape bunches, the presence of the bunch carry bag increased the half and seven-eighth cooling time by 61.1 % and 97.3 %, respectively. The addition of plastic liners over the bunch carry bag increased the half and seven-eighth cooling time by 168.9 % and 185.2 %, respectively. Non-perforated liners maintained relative humidity (RH) close to 100 % during cold storage and during a 7-day shelf-life period which resulted in delaying the loss of stem quality but significantly (P  0.05) while increasing the incidence of SO2 injury and berry drop during storage compared with perforated liners. INTRODUCTION In most fresh food refrigeration systems, heat is transferred primarily by forced convection, where cold air is forced through food packages; therefore, the temperature and its homogeneity is largely governed by the patterns of the airflow (Smale et al., 2006; Zou et al., 2006). Table grapes are non-climacteric fruit and therefore should be harvested when reaching optimum maturity (Ginsburg et al., 1978; Hardenburg et al., 1986). However, fruit quality tends to deteriorate rapidly during postharvest handling and storage, thus reducing shelf-life during marketing. Deterioration of table grape quality is mainly characterised by stem (rachis) dehydration and browning, fruit weight loss and colour change, accelerated berry softening, berry shatter and high incidence of berry decay due mainly to Botrytis cineria. Table grapes are packed in multi-layered packaging which includes the carton boxes with multiple inner-packaging materials including carton liner films, SO2 pads, moisture absorption sheets and bunch carry bags (Ngcobo et al., 2011). Resistance to airflow may even be higher during table grape cooling due to the fact that berry bunches are packed inside multi-layered packages. It is therefore important to understand the effects of packaging materials and produce on airflow in order to fully understand cooling patterns and moisture transfer properties for the design of efficient cooling systems. The aim of this experiment was to investigate the effects of multi-layered packaging on airflow and cooling patterns and on external quality attributes of table grapes during cooling and storage. MATERIALS AND METHODS

Effect of pre-harvest calcium chloride and ethanol spray on quality of 'El-Bayadi' table grapes during storage

Grapes ( Vitis vinifera L.) are highly perishable due to postharvest fungal decay and softening. The effects of pre-harvest calcium chloride (CC) (at 1 or 2 %) and ethanol (at 10 or 20 %) spray at 30 and 7 days before harvest on quality of 'El-Bayadi' table grapes during cold storage at 0 °C ± 1 plus 1 day of shelf life at 20 °C were evaluated. Pre-harvest spray of CC and ethanol at both low and high concentrations significantly decreased berry decay percentage during storage compared to control. The combination between CC and ethanol also decreased decay compared to control but was less effective than each one alone. In this respect, there were no significant differences between low and high concentration of CC and ethanol. In all treatments, decay was recorded after 30 days of storage and significantly increased to reach 26.3 % after 50 days. CC spray alone, at both concentrations, increased weight loss percentage compared to control and most other treatments. However ethanol spray especially at 20 % decreased weight loss compared to other treatments except for 10 % ethanol spray. The combination between CC and ethanol, however, increased weight loss compared to control except for, 1 % CC plus 20 % ethanol and 2 % CC plus 10 % ethanol. Weight loss percentage increased during storage to reach 2.30 % after 50 days of storage. However, the overall quality characteristics of berries as firmness, TSS, acidity, TSS/acid ratio, pH, vitamin C, total phenols and soluble tannins were not negatively affected by both CC and ethanol spray treatments. Also, both CC and ethanol spray caused neither foliar damage on the vines nor significant changes in berry quality. It is concluded that pre-harvest spray of 1 % CC or 20 % ethanol could be suggested as practical alternatives to synthetic fungicides and SO2 to decrease postharvest decay and improve quality of 'El-Bayadi' table grapes.

Analysis the Application of Environmental Properties of SO&lt;sub&gt;2&lt;/sub&gt; Fungicide for Extended Storage Life of Muscate Table Grapes at Room Temperature

The germicidal bags which can release environmental properties of SO2 fungicide, have lower water vapor transmission rate and higher oxygen transmission rate, and theirs effect on preservation of table grapes was investigated during storage at room temperature. The results showed that germicidal bags were able to maintain physicochemical, and physiological quality of grapes at a higher level compared with the common LDPE bags. At 16th days, decreases in the water loss rate, berry decay rate, and contents of total soluble solids, titratable acidity of germicidal bags groups were significantly inhibited. Although the content of TSS, TA and the berry firmness didn't show the significant difference between the germicidal bags and control group, but decay rate, shatter rate, and water loss rate of the control group were increased to 5.01%, 13.58%, and 0.67%, respectively. The control group had lost edible value. The overall results expressed that grapes quality can be maintained effectively at least for 16 days using germicidal bags.

Extending the Shelf Life of Victoria Table Grapes by High Permeability and Fungicide Packaging at Room Temperature

Grapes are one of the most delicious fruits in the world, but normally, they only have a short shelf life at room temperature, a result of their susceptibility to body water loss and grey mould infection. In this study, we developed an active packaging film (APF), which has a sandwich structure with outer and inner layers made of zeolite‐modified low‐density polyethylene (LDPE) with fungicide additives between the two layers. The APF has high permeability for oxygen and is capable of continuously releasing low‐concentration sulfur dioxide over 48 days. The grape storage experiments showed that the shelf life of Victoria table grapes packaged in these APF‐made bags at room temperature was extended to 18 days, compared with 14 days for conventional LDPE packaging and 10 days for unpackaged grapes. At 18 days' storage in APF packaging bags, water loss, berry shatter and berry decay were less than 0.5%, 3% and 5%, respectively, whereas the total soluble solid content and firmness changed only slightly. Copyright © 2012 John Wiley &amp; Sons, Ltd.

포도 품종간 송이 부위별 생리적 특성과 수확 후 냉각과 유통성 관계

Rapid loss of grape berry quality after harvest occurs due to poor postharvest management. Understanding physiological properties between cultivars is required to develop practical technologies to control fast quality deterioration of tables grapes. Physiological characteristics of whole cluster, rachis and berries were examined to find their effects on postharvest behaviour of table grapes. 'Tamnara' showed high respiration rate and browning of rachis compared to 'Campbell Early'. Weight loss of rachis of 'Cheongsoo' was highest of three cultivars. Berry decay in 'Cheongsoo' begins at the connection portion between peduncle and berry, and berry decay of 'Cheongsoo' was the most severe among three cultivars. Precooling at <TEX>$0^{\circ}C$</TEX> showed better results than cooling at <TEX>$10^{\circ}C$</TEX> regardless of cultivars but cooling effect decreased when simulated marketing period increased up to 10 days. Plastic film wrapping was effective on reducing decay in general but not at higher marketing temperature. For successful commercialization of newly developed grapes, the inhibition technology of rachis browning in 'Tamnara' is required and decay control in 'Cheongsoo' through establishment of cold chain system is recommended.

A FRUIT RIPENING MODEL AND STORAGE CHARACTERISTICS OF BLUEBERRY

The rate of maturation and changes in percent soluble solids and rate of decay of three blueberry cultivars, ‘Blomidon’, ‘Northcountry’ and ‘Northland’, under two experimental conditions were studied. The cultivars reached berry maturity concurrently in about 10 to 26 days from immature green stage. Berry development from blue-pink to fully mature required about 3 to 6 days. The percent soluble solids was lower at the green fruit stage than other stages, ‘Blomidon’ was the lowest, reaching 7.3%. From first blue stage to mature, percent soluble solid increased, reaching 14.3%, with ‘Northcountry’ having the fastest rate of increase. Temperature affected the rate of increase in percent soluble solids and percent berry decay. ‘Northland’ had the highest decay after 12 days of storage at room temperature, 62.3%. The storage life of the three cultivars, from high to low, were in the order of ‘Northland’ > ‘Northcountry’ > ‘Blomidon’.

Effects of modified atmosphere packing and honey dip treatments on quality maintenance of minimally processed grape cv. Razaki (V. vinifera L.) during cold storage

Increasing pressure in food conservation sector to replace chemical applications has urged researchers to focus on studying new strategies of extending the postharvest life of produces. In such efforts, numerous materials have been tested for their effectiveness as well as suitability in organic consumption. In this study, effects of modified atmosphere packing (MAP) and honey solution dip on maintenance of quality of minimally processed table grape cv. Razaki were investigated. During the storage at 0°C with relative humidity of 90%, MAP, honey dip, and their combined applications significantly retarded the weight loss of berries that retained about 2mm of cap stem. Soluble solid contents of all berries slightly increased, while their acid amounts decreased, resulting in consecutive rises of maturity index. With respect to the sensory score, calculated as mean of ten panelists, honey treatment alone was ranked the highest while control berries had significantly lower value. Overall, MAP, honey solution dip or their combination significantly maintained the general quality of minimally processed grape by delaying quality loss and berry decay. Therefore, honey solution dip yielded promising results to use as an edible organic coating barrier to moisture and resist to water vapor diffusion during the cold storage, offering a good adherence to berry surface.

Use of Combinations of Commercially Relevant O2 and CO2 Partial Pressures to Evaluate the Sensitivity of Nine Highbush Blueberry Fruit Cultivars to Controlled Atmospheres

We tested the impact of storage atmospheres in which the CO2 and O2 percentages sum to 21% on highbush blueberry (Vaccinium corymbosum L.) fruit condition and quality. The CO2 and O2 combinations, in percent composition, were 19%/2%, 18%/3%, 16.5%/4.5%, 15%/6%, 13.5%/7.5%, 12%/9%, 6%/15%, and 0%/21% for CO2/O2, respectively. Nine blueberry cultivars were evaluated (Duke, Toro, Brigitta, Ozarkblue, Nelson, Liberty, Elliott, Legacy, and Jersey) after 8 weeks of controlled atmosphere (CA) storage at 0 °C. Surface mold, berry decay, skin reddening (associated with fruit pulp browning), fruit firmness, pulp discoloration, and the content of ethanol and acetaldehyde were assessed. Fruit firmness, skin reddening, and decay declined and the proportion of fruit with severe internal discoloration tended to increase as CO2 concentrations increased. Ethanol and acetaldehyde accumulation was minimal, indicating fermentation was not induced by the atmospheric conditions applied. Cultivar effects were far more pronounced than atmosphere effects. Some cultivars such as Duke, Toro, Brigitta, Liberty, and Legacy appear to be well suited to extended CA storage, whereas other cultivars such as Elliott stored moderately well, and Ozarkblue, Nelson, and Jersey stored poorly. The data indicate that responses to high levels of CO2, while O2 is maintained at its maximum level practicable, can, in a cultivar-dependent manner, include significant negative effects on quality while achieving the desired suppression of decay.