• Korean Journal of Food Science and Technology
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• v.52 no.5
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• pp.503-509
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• 2020

The present study investigated the effects of dry and moist heat treatments on total phenols, total anthocyanins, and antioxidant activity levels in black chokeberry (Aronia melanocarpa) fruits. Lyophilized chokeberry powder samples were heated in a drying oven at 60, 100, 160, 180, and 200℃ for 20, 40, or 60 min. Finely ground fresh chokeberry fruits were heated in water at 60, 80, and 100℃ for 20 min, and bioactive compound and antioxidant activity levels were measured. The bioactive compounds and antioxidant activity decreased with increasing temperature and treatment duration. Antioxidant activity was preserved at 160℃ or lower without significant loss for dry heating, whereas moist heat treatment increased both bioactive compounds and antioxidant activity with increasing temperature.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.88-97
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• 2017

This study explored the physicochemical and nutritional changes associated with storage duration of fresh tomatoes. Fruits of the 'TY Megaton' and 'Yureka' tomato cultivars were harvested at the pink stage and stored at $12^{\circ}C$ for 20 days. During storage, firmness, weight loss, skin color (Hunter L, a, b, a / b values), soluble solids content (SSC), titratable acidity (TA), pH, antioxidant contents (lycopene, ascorbic acid, and total phenolics) and antioxidant activity were evaluated. Firmness was above the minimum marketable limit and fresh weight loss was below maximum acceptable weight loss after 3 weeks of storage, and no deleterious effect on antioxidant contents or activities were observed. Significant differences in SSC, TA, and pH were seen between varieties, but not between fruits stored for different durations. In both varieties, Hunter a values increased more than five-fold after 8 days of storage; this correlated with a more than four-fold accumulation of lycopene after two weeks of storage. The antioxidant activity of tomatoes was highest at the beginning of the storage period, likely because of the effective DPPH - reducing power of ascorbic acid and total phenolics. Antioxidant activity increased after 12 days of storage because of increasing lycopene content. Hence, this study indicates that pink - stage tomatoes may be stored at $12^{\circ}C$ for up to 3 weeks without affecting marketability or nutritional value.

• Journal of Microbiology and Biotechnology
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• v.29 no.10
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• pp.1553-1560
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• 2019

In a previous study, the antimicrobial peptides extracted from Lactobacillus plantarum UTNGt2 of wild-type fruits of Theobroma grandiflorum (Amazon) were characterized. This study aimed to investigate the antimicrobial mechanisms of peptides in vitro and its protective effect on fresh tomatoes. The addition of partially purified Gt2 peptides to the E. coli suspension cells at the exponential ($OD_{605}=0.7$) growth phase resulted in a decrease with 1.67 (log10) order of magnitude compared to the control without peptide. A marginal event (< 1 log10 difference) was recorded against Salmonella, while no effect was observed when combined with EDTA, suggesting that the presence of a chelating agent interfered with the antimicrobial activity. The Gt2 peptides disrupted the membrane of E. coli, causing the release of ${\beta}$-galactosidase and leakage of DNA/RNA molecules followed by cell death, revealing a bacteriolytic mode of action. The tomatoes fruits coated with Gt2 peptides showed growth inhibition of the artificially inoculated Salmonella cocktail, demonstrating their preservative potential.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.196-201
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• 2015

Lysophosphatidylethanolamine (LPE) affects the quality of flowers, fruits, and other horticultural products. Studies have provided evidence that LPE can accelerate ripening of fruits and prolong shelf-life at the same time. In this study, the influence of LPE on anthocyanin accumulation and phytochemical characteristics of sweet cherry was investigated. LPE ($10mg{\cdot}L^{-1}$) was applied to a commercial sweet cherry c.v. '0900 Ziraat' orchard two and four weeks before harvest for two treatment years (2011 and 2012). Preharvest applications of LPE resulted in significant improvement in both pomological and phytochemical attributes at harvest. LPE treatment led to a 17% increase in fruit weight and a 6% increase in soluble solid content when averaged over two experimental years. Fruit phytochemical content and antioxidant capacity were increased significantly. The average total phenolic content of LPE-treated fruits for the two years was $703{\mu}g$ gallic acid equivalent (GAE)/g fresh weight (g FW) compared to $569{\mu}g$ GAE/g FW in the untreated control. Fruits treated with LPE had a 27% and 16% more anthocyanin than the control fruits in 2011 and 2012. Antioxidant capacity of fruits, as measured by TEAC (Trolox equivalent antioxidant capacity) assay, was 12.5 and $11.4{\mu}mol$ TE/g FW in LPE-treated and untreated control fruits, respectively, when averaged over two experimental years. Our results suggest that preharvest application of LPE may have the potential to increase anthocyanin accumulation, improve fruit quality and enhance phytochemical characteristics of sweet cherries.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.364-371
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• 2005

Packaging bags and corrugated boxes prepared from newly developed antimicrobial packaging paper had greater ability to prolong freshness of packed fruits, and lower weight loss of fruits and microbial growth than non-treated bags and boxes. Addition of zeolite to paper greatly increased absorbance of aging hormone, $C_{2}H_{4}$, emitted from stored fruits, and contributed to decrease in putrefied fruits during storage. Water repellent agent such as alkyl ketone dimer played significant role in preventing functional paper from absorbing water from stored fruits, leading to preservation of fresh weight in stored fruits. Because rise in production cost of functional packaging paper could be offset by reduction of fruit and vegetable wastes, storing fruits and vegetables in functional paper containers was more economical than storing in non-treated containers.

• Journal of Bio-Environment Control
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• v.3 no.1
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• pp.52-57
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• 1994

The external qualities of cherry tomato fruits(Lycopersicon esculentum) grown in circulating deep flow hydroponic culture were non - destructively estimated in 1992 under warm climate conditions and evaluated in 1993-1994 under cool season. The fruit size of ‘Minicarol’ was by far the smallest compared to ‘Chelseamini’ and ‘Popo’. There were high correlations between external qualities of fruits-lengthwise growth harmonized with widthwise growth. The volume and/or weight of fruit could be non -destructively estimated by length and width of fruit. Volume=0.071$\times$ (length+width)$^3$＋0.451, Fresh weight=0.072$\times$ (length+width)$^3$＋0.542. These models were accurately evaluated by fruits harvested in 1994.

• Journal of Biosystems Engineering
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• v.30 no.5 s.112
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• pp.280-284
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• 2005

Front the production on the farm to the consumer, agricultural products are subject to various physical treatments involving mechanical techniques and devices. It is essential to understand the physical laws governing the response of these biological materials so that the machines, processes, and handling operations can be designed fur maximum efficiency and the highest quality of the end products. A compression test system was developed to test the physical properties of fruits including apple, pear, and peach which may lead to a better understanding of the physical laws. The test system consisted of a digital storage oscilloscope and simple mechanism which can apply quasi-static compression to fresh fruits. Rupture force, energy, and deformation were measured at the five levels of compression speed from 1.25 to 62.5 mm/min for each internal and external tissues. Rupture forces for apple and pear were in the range of 42.2 to 46.2 N and 38.8 to 41.2 N for external and infernal tissues, respectively. Rupture forces fir peach external tissues were in the range of 48.2 to 54.0 N.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1566-1571
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• 2005

Consumer's perception and consumption pattern of fresh-cut agri-food Products were surveyed to Provide basic information for quality enhancement. The results are summarized as follows: The respondents had a preference for a discount store (60.5$\%$) to purchase fruits and vegetables and the frequency of purchase was one time Per week (46.1$\%$). Fruits and vegetables were purchased frequently by full-time housewives compared with workers. The reasons for purchasing fresh-cut agri-food generally resulted from a consideration of the saving in cooking time, the ease of handling and the desire to serve appropriate portions. On the other hand, the reasons for not purchasing fresh-cut agri-food Products were the comparatively high price, a perception of unsanitary handling. Freshness was considered to be the most important factor when purchasing these products. The preferred price for the fresh-cut agri-food products were approximately 110 $\∼$ 140$\%$ of that for the unprocessed products. 87.7$\%$ of respondents answered that they will purchase fresh-cut agri-food products continuously if some problems that they considered, would be improved.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1526-1526
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• 2001

To improve the accuracy of sweetness sensor in automated sorting operations, it is necessary to clarify unevenness of the sugar content distribution within fruits. And it is expected that the technique to evaluate the content distribution in fruits contribute to the development of the near-infrared (NIR) imaging spectroscopy. Sugiyama (1999) had succeeded to visualize the distribution of the sugar content on the surface of a half-cut green fresh melon. However, this method cannot be applied to red flesh melons because it depends on information of the absorption band of chlorophyll (676 nm), which is affected by the color of the fresh. The objective of this study was to develop the universal visualization method depends on the absorption band of sugar, which can be applied to various kinds of melons and other fruits. The relationship between the sugar contents and absorption spectra of both green and red fresh melons were investigated by using a NIR spectrometer to determine the absorption band of sugar. The combination of 2$\^$nd/ derivative absorbances at 902 nm and 874 nm was highly correlated with the sugar contents. The wavelength of 902 nm is attributed to the absorption band of sugar. A cooled charge-coupled device (CCD) imaging camera which has 16 bit (65536 steps) A/D resolution was equipped with rotating band-pass filter wheel and used to capture the spectral absorption images of the flesh of a vertically half-cut red fresh melon. The advantage of the high A/D resolution in this research is that each pixel of the CCD is expected to function as a detector of the NIR spectrometer for quantitative analysis. Images at 846 nm, 874 nm, 902 nm and 930 nm were acquired using this CCD camera. Then the 2$\^$nd/ derivative absorbances at 902 nm and 874 nm at each pixel were calculated using these four images. On the other hand, parts of the same melon were extracted for capturing the images and squeezed for the measurement of sugar content. Then the calibration curve between the combination of 2$\^$nd/ derivative absorbances at 902 nm and 874 nm and sugar content was developed. The calibration method based on NIR spectroscopy techniques was applied to each pixel of the images to convert the 2$\^$nd/ derivative absorbances into the Brix sugar content. Mapping the sugar content value of each pixel with linear color scale, the distribution of the sugar content was visualized. As a result of the visualization, it was quantitatively confirmed that the Brix sugar contents are low at the near of the skin and become higher towards the seeds. This result suggests that the visualization technique by the NIR imaging spectroscopy could become a new useful method fer quality evaluation of melons.

• Korean Journal of Environmental Agriculture
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• v.39 no.2
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• pp.138-141
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• 2020

BACKGROUND: Fresh weight is one of the major quality measurement factors in determining the quality of fresh fruits. A practical method has been developed for rapid and non-destructive measurement using the Chlorophyll Fluorescence Image (CFI) technique to estimate changes in fresh weight of post-harvest products. METHODS AND RESULTS: Kiwifruit (Actinidia deliciosa) was used and measured for the fresh weight and CFI under different temperature conditions at 0, 10, and 20℃, from 0 to 21 days after storage (DAS). We observed the fresh weight of kiwifruit and measured the surface image for determining F_v/F_m value in terms of maximum quantum yield on each day. To estimate freshness of kiwifruit we applied linear regression between the measured fruit weights and F_v/F_m values. Results showed that fruit weights were reduced by 4% at 0℃, 6% at 10℃, and 14% at 20℃ for 21 days, respectively. And also, the value of Fv/Fm was shown as decreasing trend at all temperature conditions, especially at 20 ℃. Fv/Fm values showed highly significant correlation (R²>0.9) with fresh weight of kiwifruit at all different storage temperatures. CONCLUSION: Thus, CFI technique can be useful to estimate the fresh weight of kiwifruit.