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This study evaluated the effect of sterilizing harvesting knives with sodium hypochlorite (NaOCl) on soft rot in Kimchi cabbage. Knives were infected with Pectobacterium carotovorum subsp. carotovorum (Pcc), sterilized with NaOCl (100, 200, and 300 mg/L), and used to cut Kimchi cabbage slices, which were incubated for 70 h in a 28 °C incubator. In Kimchi cabbage slices cut with a Pcc-inoculated knife without NaOCl sterilization, symptoms began to appear after 20 h, and approximately 60% of the cabbage slices were infected after 70 h of incubation. In contrast, in cabbage cut with a sterilized knife, soft rot symptoms were delayed, and they began to appear after 40 h of incubation in the 200 mg/L-treated. The expression levels of PG10, PG12-1, PG12-3, WRKY 33, MPK3, ACO1, and ACO2 were increased in infected plants, and NaOCl treatment decreased these expression levels. Transmission of soft rot can be minimized by disinfecting harvesting knives with 200 mg/L NaOCl.

Various hilling materials (rice hulls, pine sawdust, and perlite) were compared to produce sprout vegetables using beach silvertop (Glehnia littoralis Fr. Schm. ex Miq.). We have investigated the yield, total phenolic content, total flavonoid content, antioxidant capacities (DPPH, ABTS), phenolic compounds, and volatile compounds of G. littoralis sprout vegetables. Comparing the yield and phenolic compounds according to the hilling materials, the rice hulls treatment was the most and followed by sawdust and perlite. The leaves and stems of G. littoralis sprout vegetable contain approximately 27 volatile compounds. The sawdust treatment had a pine scent even during the hilling process, and these scent components were entirely absorbed by the stem. The result suggested that sawdust treatment, like rice hulls, had a high yield and high content of beneficial compounds, but the stem of G. littoralis had a pine tree scent, reducing the inherent scent of G. littoralis.

The purpose of this study was to investigate the quality characteristics of ripe fruit based on harvest date and to examine the ripening phase of ‘Seolhyang’ strawberry suitable for room temperature, cold-chain, and low temperature distribution. The strawberries were harvested six times between December 20 to May 9. The appropriate maturity of strawberries is characterized by the firmness of approximately 2.9–3.0 N, and SSC remained above 8.6 °Brix until March and declined after April. The quality index values that determine the maturity stage of strawberries should be red color, Hunter a value ranging from 32 to 37, and hue angle of 36-45°. For the after-ripening experiment, the progression rate of the ripening stage determined based on strawberry color was 10%/day at room temperature, 5%/day at 10-12°C, and 3%/day at 5°C. Thus, strawberries should be harvested at 80% coloring stage for distribution at room temperature and at least 90% for low temperature storage to maintain the merchantability. Besides, strawberries harvested at 70% coloring stage at room temperature and strawberries harvested below 80% coloring stage at low temperatures below 5°C had lost commercial value before reaching 100% coloring stage.

Improved methods are needed to extend the shelf life of strawberry fruits. The objective of this study was to determine the postharvest physiological mechanism of high-CO2 treatment in strawberries. Harvested strawberries were stored at 10 °C after 3 h of exposure to a treatment with 30% CO2 or air. Pectin and gene expression levels related to cell wall degradation were measured to assess the high-CO2 effects on the cell wall and lipid metabolism. Strawberries subjected to high-CO2 treatment presented higher pectin content and firmness and lower decay than those of control fruits. Genes encoding cell wall-degrading enzymes (pectin methylesterase, polygalacturonase, and pectate lyase) were downregulated after high-CO2 treatment. High-CO2 induced the expression of oligogalacturonides, thereby conferring defense against Botrytis cinerea in strawberry fruits, and lowering the decay incidence at seven days after its inoculation. Our findings suggest that high-CO2 treatment can maintain strawberry quality by reducing decay and cell wall degradation.

In Korea, to prevent the extinction of Glehnia littoralis, a cultivation method to improve productivity is being studied and quality maintenance technology is required after harvest. The objective of this study was to determine the effect of MAP on the postharvest quality of G. littoralis. The control showed a weight loss rate of more than 5% after 3 days of storage and lost its marketability, whereas MAP treatment (PE or MPE) showed a weight loss rate of about 2–3% during storage for more than 30 days. In the control, MDA and electrolyte leakage increased due to chilling injury. The total chlorophyll content was low and remained constant until about 23 days of storage in the PE treatment group and 15 days in the MPE treatment group. Among the phenolic compounds, chlorogenic acid, rutin, isoquercetin, and nicotiflorin were maintained at significantly higher levels in the PE than in the MPE. In addition, bergapten showed a highly significant upward trend in the MPE, especially after 25 days of storage when the yellowing progressed. In conclusion, MAP treatment effectively maintains quality while minimizing lipid peroxidation and maintaining phenolic compounds during low-temperature storage after harvest of G. littoralis.

Improved methods are needed to extend the shelf life of strawberry fruits. The objective of this study was to determine the postharvest physiological mechanism of high-CO2 treatment in strawberries. Harvested strawberries were stored at 10 °C after 3 h of exposure to a treatment with 30% CO2 or air. Pectin and gene expression levels related to cell wall degradation were measured to assess the high-CO2 effects on the cell wall and lipid metabolism. Strawberries subjected to high-CO2 treatment presented higher pectin content and firmness and lower decay than those of control fruits. Genes encoding cell wall-degrading enzymes (pectin methylesterase, polygalacturonase, and pectate lyase) were downregulated after high-CO2 treatment. High-CO2 induced the expression of oligogalacturonides, thereby conferring defense against Botrytis cinerea in strawberry fruits, and lowering the decay incidence at seven days after its inoculation. Our findings suggest that high-CO2 treatment can maintain strawberry quality by reducing decay and cell wall degradation.

This study was conducted to investigate the nutrient composition of everbearing strawberry cultivar grown on highlands of Gangwon province after harvest. Various phytochemical compositions such as ascorbic acid, anthocyanin, malondialdehyde, and phenolic compounds were analyzed in strawberry fruits from five different cultivars (cv. Albion, Flamenco, Goha, San Andreas, and Seascape). Ascorbic acid content was similar among five cultivars at 20 mg 100 g(−1), whereas major pigment anthocyanin in Seascape was higher than in any other cultivars. Goha and San Andreas showed higher total phenolic compound contents. The effect of room or forced-air precooling on Flamenco and Goha was studied. Higher weight loss was observed in Flamenco treated with forced-air cooling, while in Goha both precooling treatments induced weight loss. Both precooling treatments were effective to maintain firmness in two strawberry cultivars. Forced air cooling maintained total phenolic contents until 12 days of storage, and the efficiency accelerated by low temperature storage.

Kimchi cabbage ‘Choon Gwang’ cultivar that was grown in highlands in Gangneung was subjected to predrying, room cooling, and forced air cooling, and then packed with/without 0.02 ㎜ HDPE film to investigate the effect of postharvest treatment on quality characteristics during 8 weeks storage at 2℃ (RH 90 ± 5%). Weight loss in forced air cooling and room cooling was lower than 3-4% with 0.02 ㎜ HDPE film liner treatment during storage. However, it was only below 10% in room cooling without liner treatment and forced air cooling without liner treatment led to the highest weight loss, above 15%. Conversely, the control had lower weight loss than the others. SSC was 2-4°brix for all treatments and there was no difference between postharvest treatments and liner treatments. Color index and firmness both showed no differences with/without 0.02 ㎜ HDPE film and postharvest treatments. In sensory evaluation, forced air cooling with liner treatment was effective, with the highest score, especially in appearance and crispness. After 6 weeks, control kimchi cabbage without liner treatment was damaged seriously in appearance and the internal color had changed to brown. Room cooling and predrying with liner treatment changed the start of internal browning to after 8 weeks storage.

The effect of nitric oxide (NO) treatment on the quality of kiwifruit, cv. Hayward, was studied at room temperature after cold storage for one or three months at 0°C. Kiwifruits cold-stored for one month were treated with 200 μL·L -1 NO and subsequently transferred to room temperature to monitor quality changes over the course of their shelf life. Weight loss was high in fruits not treated with NO. Ethylene production was delayed for two days by NO treatment, and respiration rate was reduced to less half than that of the control. The kiwifruits stored for three months were treated with N2 and 100, 200, or 500 μL·L -1 NO, or air alone. The highest weight loss was observed in kiwifruit treated with 100 μL·L -1 NO. While ethylene production was high in fruits treated with 100 μL·L -1 NO and without the treatment, it was relatively low in the kiwifruit treated with 200 and 500 µL·L -1 NO. Firmness was abruptly decreased in fruits not treated with NO, while the kiwifruit exposed to 200 μL·L -1 NO maintained the same levelf firmness for 9 days at room temp erature.n addition,rowth of Botrytis cinerea was inhibited by NO as compared with the air and N2 treatments. Our findings indicate that NO can be used effectively for prolonging shelf life and maintaining fruit quality during distribution after cold storage. The optimum NO concentration for cold-stored kiwifruits was found to be 200 μL·L -1 .

This study was conducted to investigate the quality characteristics of eight everbearing strawberry cultivars and the effect of precooling treatment to maintain the quality during storage and shelf life of 'Charlotte'. Several quality parameters including firmness, soluble solids content (SSC), color, soluble sugars, and organic acids were evaluated. For Successful marketing everbearing strawberries required more than 1 N of firmness and of SSC, respectively. 'Albion', 'Charlotte', and 'Goha' cultivars were higher in fruit SSC and 'Charlotte' cultivar was higher in fruit firmness among eight cultivars examined in this study. Fruit had more bright red color in 'Charlotte', 'Flamingo', 'GW-4', and 'San Andreas', which may reflect the consumer acceptance. Physicochemical characteristics of 'Charlotte' strawberry after with/without room precooling treatment were evaluated during storage at , , and and additional 3 days at for shelf-life. Weight loss increased about 8% in the fruits stored at for 3 days, while in low temperature storage was about 2% for 7 days showing precooling was more effect on during shelf life periods rather than storage periods. Decay was not found during storage at regardless of precooling treatment, but fungal growth was found in all the treatments after transferred to room temperature. Precooling treatment did not affect fruit color in shelf life period. For advanced marketing, everbearing strawberry should maintain in low temperature less than to sustain quality, but the room precooling showed less significant effect to maintain quality on 'Charlotte' cultivar.

This study was conducted to investigate the quality characteristics of eight Kimchi cabbage cultivars and the effect of cold storage on the quality of two kinds of cabbage cultivars, such as 'CR-Nongshim', and 'Ryouckgwang'. Early planted and harvested cultivars at July showed that fresh weight was lower than late harvested cultivars at September, because early harvesting time of July was heavy rainy season at highlands of Gangwon province. The firmness was more than 10 N for all cultivars and 'Cheongock', 'Sanjanggoon', and 'Ryouckgwang' cultivars had high value of firmness among them. No differences among the cultivars were found in appearance, freshness, and texture evaluations at harvest. Sweetness and bitterness had statistical differences and showed high value in 'Ryouckgwang' and in 'CR-Nongshim' and 'Sooho'. Two Kimchi cabbage cultivars such as 'CR-Nongshim' and 'Ryouckgwang' were stored at , , , and room temperature () with more than 90% RH. Significant difference was found in weight loss during room and low temperature storage. In general, weight loss of the Kimchi cabbages at room temperature was significantly increased by 15% within 3 days, whereas it was delayed at low temperature until 3 weeks on all Kimchi cabbage cultivars. Firmness of 'CR-Nongshim' was higher than 'Ryouckgwang' but there was no difference within low storage temperatures. Appearance among the sensory factors was a critical indicator to estimate storage periods. On the point of appearance, storage period at was 1 week and and was 3 weeks and 1 week in 'CR-Nongshim' cultivar, respectively. The storage period of 'Ryouckgwang' cultivar was 2 weeks, 4 weeks, and 2 weeks, respectively. Conclusively, storage at with more than 90% RH was recommended as optimum temperature to maintain quality in both cultivars.

Quality changes of highbush blueberry cultivars (Vaccinium corymbosum L. cvs. Bluetta, Duke) were evaluated as influenced by transport temperature. Neither cultivar remained marketable after 6 days or 16 days at room temperature or 10°C. The ‘Duke’ cultivar had slightly lower weight loss than ‘Bluetta,’ but difference between the cultivars was not significant after 12 days of storage. Decrease of fruit firmness was delayed by storage at 10°C for both cultivars, with ‘Duke’ blueberries being firmer than ‘Bluetta’. Soluble solids content was 9.9 ± 0.3 °Brix for both cultivars, which was lower than previous reports, probably as a result of weather conditions before harvest. Organic acid content declined in both cultivars during storage. Hue value of the ‘Bluetta’ cultivar was higher (more purple-blue) than the ‘Duke’ cultivar, but Hunter L and hue angle did not change during storage. Fruit characteristics at harvest and postharvest maintenance of low temperature are clearly important factors affecting the post-harvest fruit quality during transportation and storage.

Nitric oxide (NO) was applied to broccoli (Brassica oleracea L. var. italica) florets and analyzed its effect on chlorophyll degradation during postharvest senescence. Florets were treated with 1000 µL/L of NO for 5 h and placed in darkness at 20°C. During storage, the NO treatment delayed yellowing and retarded the onset of chlorophyll degradation. The activity of lipoxygenase was not related to the development of yellowing during storage. However, the accumulation of malondialdehyde, which could be used as an index of lipid peroxidation, was higher in the control than observed in the NO treatment. In untreated broccoli florets during storage, lipid peroxidation influenced the yellowing of broccoli florets while NO-treated florets maintained chlorophyll levels and decreased lipid peroxidation.

Edible coating may enhance the boundary layer resistance resulting in enhanced shelf life of fruits. Plums (Prunus salicina Lindl. cv. ‘Sapphire’) were treated with coating material based on carbohydrate (Versasheen) with sorbitol as plasticizer and stored at 20 °C and 85% RH. The influence of coating on the gas transmission rates was estimated using a carrier of 100% cellulose paper. Coating treatment reduced the transmission rate of CO2, O2, and H2O. Changes in fruit weight, fruit flesh firmness, color parameters (L*, a*, and hue angle), soluble solids content, pH, titratable acidity, ethylene, CO2, malondialdehyde (MDA), and VIS/NIR fruit reflectance spectrum were recorded in 2-day interval. Edible coating was effective in delaying the increase of pH and the loss of firmness, titratable acidity, L*, hue angle, and MDA. The incorporation of sorbitol showed beneficial effects on decreasing the weight loss, CO2, and ethylene exchange. In the room temperature storage period, not only fruit ripening was measurable in the VIS (350–750 nm) and NIR (750–1,400 nm) wavelength ranges due to the decrease in the fruit chlorophyll absorption but also water loss, respectively. After 5-day room temperature storage the chlorophyll absorption peak in the spectra was already beyond the detection limit in all treatments, while after 3-day storage, the coating effect on the spectral intensities was feasible to separate control from coated plums.

Fresh apple juice was heated at 95 °C for 30 and 60 min, and then stored for 6 days for obtaining different extent of non-enzymatic browning. Front-face fluorescence excitation–emission-matrix (EEM) with excitation at 355 and 400 nm and emission ranges of 385–600, and 430–600 nm was used to measure the juice samples. The sign test pointed out an enhanced sensitivity of EEM compared to commonly used browning indicators, such as non-enzymatic browning index (NEBI), color readings in L∗a∗b∗ space, and the concentration of 5-hydroxymethylfurfural (HMF). Using the fluorescence data, the correctness of classifications of fresh juice, heated juice, and stored juice were >85%. Multivariate analyses were applied to study the relations of fluorescence emission spectra and common indicators. For predicting NEBI, b∗, and HMF, the correlation coefficients were >0.80. Resulting, the spectroscopic analyses of fluorescent neoformed products such as HMF provide a feasible approach to monitor non-enzymatic browning of juice.

The nitric oxide (NO) treatment on tomato (Solanum lycopersicum L. cv. ‘Myrock’) fruits delayed the burst of ethylene production and color development in both mature green (MG) and breaker (BR) stage fruits. However, no clear differences were observed in pink and full red stage fruits during storage. The gene expressions of 1-aminocyclopropane-1-carboxylic acid synthase (ACS) and 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) were determined in both MG and BR stage fruits using the reverse transcription-polymerase chain reaction method. The analyzed ACS genes include LeACS2, LeACS4, LeACS6, LeACSH6A, and LeACSH6B. The gene expression of ACO was investigated on LeACO1, LeACO2, LeACOH2, LeACO4, and LeACOH4. The ACS genes in NO-treated and untreated fruits were expressed extensively over the storage period in both MG and BR stage fruits, and the expression patterns were similar. However, the expression of ACO genes was different at different ripening stages. In NO-treated fruit, expression of LeACO1, LeACOH2, and LeACO4 was decreased and delayed. These results implicate that NO might control the postharvest metabolism of crops, dependent on either dose level or commodities.

Seedling-lethal phenotypes of Arabidopsis (Arabidopsis thaliana) mutants that are defective in early steps in the sterol biosynthetic pathway are not rescued by the exogenous application of brassinosteroids. The detailed molecular and physiological mechanisms of seedling lethality have yet to be understood. Thus, to elucidate the underlying mechanism of lethality, we analyzed transcriptome and proteome profiles of the cyp51A2 mutant that is defective in sterol 14α-demethylation. Results revealed that the expression levels of genes involved in ethylene biosynthesis/signaling and detoxification of reactive oxygen species (ROS) increased in the mutant compared with the wild type and, thereby, that the endogenous ethylene level also increased in the mutant. Consistently, the seedling-lethal phenotype of the cyp51A2 mutant was partly attenuated by the inhibition of ethylene biosynthesis or signaling. However, photosynthesis-related genes including Rubisco large subunit, chlorophyll a/b-binding protein, and components of photosystems were transcriptionally and/or translationally down-regulated in the mutant, accompanied by the transformation of chloroplasts into gerontoplasts and a reduction in both chlorophyll contents and photosynthetic activity. These characteristics observed in the cyp51A2 mutant resemble those of leaf senescence. Nitroblue tetrazolium staining data revealed that the mutant was under oxidative stress due to the accumulation of ROS, a key factor controlling both programmed cell death and ethylene production. Our results suggest that changes in membrane sterol contents and composition in the cyp51A2 mutant trigger the generation of ROS and ethylene and eventually induce premature seedling senescence.