• Journal of Biosystems Engineering
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• 제37권4호
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• pp.252-257
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• 2012

Purpose: The net rind pattern and color of melon surface are important for a high market value of melon fruits. The development of the net and color are closely related to the changes in shape, size, and maturing. Therefore, the net and color characteristics can be used indicators for assessment of melon quality. The goal of this study was to investigate the possibility of estimating melon soluble solids content (SSC) and firmness by analyzing the net and color characteristics of fruit surface. Methods: The true color images of melon surface obtained at fruit equator were analyzed with 18 color features and 9 texture features. The partial least squares (PLS) method was used to estimate SSC and firmness in melons using their color and texture features. Results: In sensing melon SSC, the coefficients of determination of validation (${R_v}^2$) of the prediction models using the color and texture features were 0.84 (root mean square error of validation, RMSEV: 1.92 $^{\circ}Brix$) and 0.96 (RMSEV: 0.60 $^{\circ}Brix$), respectively. The ${R_v}^2$ values of the models for predicting melon firmness using the color and texture features were 0.64 (RMSEV: 4.62 N) and 0.79 (RMSEV: 2.99 N), respectively. Conclusions: In general, the texture features were more useful for estimating melon internal quality than the color features. However, to strengthen the usefulness of the color and texture features of melon surface for estimation of melon quality, additional experiments with more fruit samples need to be conducted.

• Journal of Biosystems Engineering
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• 제37권3호
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• pp.166-176
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• 2012

Purpose: This study was conducted to investigate the potential of interactance mode of NIR spectroscopy technology for the estimation of soluble solids content (SSC) and firmness of muskmelons. Methods: Melon samples were taken from local greenhouses in three different harvesting seasons (experiments 1, 2, and 3). The fruit attributes were measured at the 6 points on an equator of each sample where the spectral data were collected. The prediction models were developed using the original spectral data and the spectral data sets preprocessed by 20 methods. The performance of the models was compared. Results: In the prediction of SSC, the highest coefficient of determination ($R_{cv}{^2}$) values of the cross-validation was 0.755 (standard error of prediction, SEP=$0.89^{\circ}Brix$) with the preprocessing of normalization with range in experiment 1. The highest coefficient of determination in the robustness tests, $R_{rt}{^2}$=0.650 (SEP=$1.03^{\circ}Brix$), was found when the best model of experiment 3 was evaluated with the data set of experiment 2. The best $R_{cv}{^2}$ for the prediction of firmness was 0.715 (SEP=3.63 N) when no preprocessing was applied in experiment 1. The highest $R_{rt}{^2}$ was 0.404 (SEP=5.30 N) when the best model of experiment 3 was applied to the data set of experiment 1. Conclusions: From the test results, it can be concluded that the interactance mode of VIS/NIR spectroscopy technology has a great potential to measure SSC and firmness of thick-skinned muskmelons.

• Journal of Biosystems Engineering
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• 제38권3호
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• pp.185-191
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• 2013

Purpose: The present study focused on the estimation of soluble solids content (SSC) of chestnut using reflectance and transmittance spectra in range of VIS/NIR. Methods: Four species intact/peeled chestnuts were used for acquisition of spectral data. Transmittance and reflectance spectra were used to develop the best PLS model to estimate SSC of chestnut. Results: The model developed with the transmitted energy spectra of peeled chestnuts rather than intact chestnuts and with range of NIR rather than VIS performed better. The best $R^2$ and RMSEP of cross validation were represented as 0.54 and $1.85^{\circ}Brix$. The results presented that the reflectance spectra of peeled chestnuts by species showed the best performance to predict SSC of chestnut. $R^2$ and RMSEP were 0.55 and $1.67^{\circ}Brix$. Conclusions: All developed models showed RMSEP around $1.44{\sim}2.54^{\circ}Brix$, which is considered not enough to estimate SSC accurately. It was noted that $R^2$ of cross validation that we found were not high. For all that, grading of the fruits in two or three classes of SSC during postharvest handling seems possible with an inexpensive spectrophotometer. Furthermore, the development of estimation of SSC by each chestnut species could be considered in that SSC distribution is clustering in different range by species.

• 원예과학기술지
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• 제30권6호
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• pp.709-717
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• 2012

To establish the standard of ripe kiwifruit sorting, near infrared (NIR) spectroscopy was performed on kiwifruit sampled from three farms. Destructive measurements of flesh firmness, soluble solids content (SSC), and acidity were performed and compared to measurement using NIR reflectance spectrums from 408 to 2,492 nm. NIR predictions of those quality factors were calculated using the modified partial least square regression method. Flesh firmness was predicted with a standard error of prediction (SEP) of 3.32 N and with a correlation coefficient ($R^2$) of 0.88. SSC was predicted with SEP of $0.49^{\circ}Brix$ and with $R^2$ of 0.98. Acidity was predicted with SEP of 0.28% and with $R^2$ of 0.91. Kiwifruit ripened at $20^{\circ}C$ for 15 days showed uneven qualities with normal distribution. Considering the SEP of each parameter, kiwifruit after ripening treatment could be non-destructively predicted their qualities and sorted by flesh firmness or soluble solids content through NIR prediction.

• 원예과학기술지
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• 제30권2호
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• pp.158-161
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• 2012

The influence of lysophosphatidylethanolamine (LPE) on anti-senescence of melon leaves and the change in fruit quality during the storage at low temperature were studied. In most of the crops, freshness of leaves is important factor for characteristics of fruits, such as sugar contents, color, and firmness. Melon ($Cucumis$ $melo$ L. cv. Prince) plants were sprayed with LPE at 5 and 3 weeks before commercial harvest. In upper part, LPE treatment showed slight high number of fresh leaf compared to no treatment (None). However, in lower part, LPE resulted in apparent inhibition effect on senescence, showing that lower side of melon plant kept fresh upon LPE application up to about 30%. The SSC of melon treated with LPE was similar to that of fruit from None at harvest. There was no change in soluble solids content (SSC) for all treatment during the storage at $7^{\circ}C$. There were no significant differences in firmness of mesocarp from melons given different treatments at harvest. The firmness of mesocarp from melon treated with LPE was higher than none after 2 weeks storage. The electrolyte leakage means for melon treated with LPE did not differ significantly from the means at initial storage after 2 weeks storage among the treatments. None increased 57% from its initial electrolyte leakage during storage. These results suggest that the application of LPE may have potential to inhibit senescence of leaves and maintain fruit quality during the storage in melon.

• 한국환경농학회지
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• 제33권1호
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• pp.57-62
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• 2014

BACKGROUND: Defoliation in grapevine cultivation is practically used to improve light environment within the canopy and thereby fruit quality. Effects of defoliation in five-year-old 'Pione' grapevine during cultivation with heating were investigated to find out optimum ratio of leaf area to fruit cluster weight (L/F). METHODS AND RESULTS: The grapevines were defoliated with berry-thinning 20 days after full bloom to provide various levels of L/F. At harvest, total leaf area values of fruit bearing branches were between 0.23 and $0.60m^2$. With increasing L/F, soluble solids and anthocyanin contents curvilinearly increased ($R^2=0.76^{**}$). At L/F over $0.6m^2/kg$, soluble solids content (SSC) leveled off. With increasing L/F, titratable acidity (TA) linearly decreased ($R^2=0.87^{**}$), but the ratio of SSC to TA linearly increased ($R^2=0.86^{**}$). Anthocyanin content was significantly correlated with SSC and the ratio of SSC to TA ($R^2=0.80^{**}$ and $0.82^{**}$, respectively). When total leaf area per fruit bearing branch was maintained $0.40m^2$, soluble solids and anthocyanin contents linearly decreased ($R^2=0.79^{**}$ and $0.85^{**}$, respectively), but TA linearly increased with increasing fruit cluster weight ($R^2=0.70^{**}$). Fruit was low in quality when the L/F was below $0.6m^2/kg$. CONCLUSION: L/F is recommended to be maintained at least $0.6m^2/kg$ in 'Pione' grapevine during cultivation with heating to produce higher-quality fruits.

• 한국산학기술학회논문지
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• 제18권1호
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• pp.256-261
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• 2017

본 연구는 키위 과일의 수출 시 최적 수송온도를 구명하기 위하여 같은 수송조건을 설정한 시물레이션실험을 수행하였다. 수송온도로 $2^{\circ}C$와 $6^{\circ}C$ 조건을 설정하고 이와 비교한 실험군으로 변온조건으로 상온($20{\sim}28^{\circ}C$)을 두어 과실의 여러 물리화학적 변화를 조사하였다. 과실의 경도는 $2^{\circ}C$에서 가장 높게 유지되었고 이와 유기산 함량의 유지에서도 같은 결과였다. 가용성 당함량은 저온 저장 5주까지 완만히 증가하다가 그 이후 감소하기 시작하였는데 저온 처리간 차이는 크지 않았다. 이에 비하여 상온에서의 가용성 당함량은 저장 3주후에 과실이 부패하여 측정이 불가능하였다. 키위 과실의 당산비는 저온저장 5주 까지 18에서 27까지 크게 증가하여 과실의 품질이 크게 향상되다가 그 이후 감소하기 시작하였다. 이 결과로 키위는 전형적인 수확 후 호흡급등형 과실의 패턴을 보였고 저온처리 간에는 차이가 크지 않았다. 관능검사를 통하여 저장중인 키위 과육의 색을 조사한 결과, 저온처리($2^{\circ}C$와 $6^{\circ}C$)에서 차이가 크지 않았다.

• 한국자원식물학회지
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• 제33권6호
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• pp.624-637
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• 2020

High-quality and high-phytonutrient watermelon fruits have strong market opportunities besides their health related benefits. Hence, investigating quality and nutritional related traits of watermelon genetic resources could provide important baseline data in breeding for increased lycopene content thereby increasing the marketability of watermelon. To this end, we have examined some fruit morphological traits and lycopene content of 105 genetic resources. Seeds, originally obtained from 22+ countries, were obtained from the National Agrobiodiversity Center, Jeonju, South Korea, grown in an experimental field and harvested at a fully mature stage. The size of pistil scar (SPS), the width of stripes (WS), weight of fruit (WF), length of fruit (LF), width of fruit (WIF), the thickness of pericarp (TP), soluble solids content (SSC), fruit shape in longitudinal section, ground color of skin, the intensity of the green color of skin, fruit shape at the apical part, grooving distribution, conspicuousness of stripes, and main color of the flesh were recorded on the field and inside laboratory and the lycopene was measured using spectrophotometric and HPLC methods. Watermelon fruits have shown a diverse morphological characters. Red and pink fleshed fruits dominated in the entire collections. Fruits with higher thickness of rind were found to exhibit less soluble solid content (SSC). Korean origin fruits were characterized by intermediate SSC while the United States of America (USA), Russia (RUS), Tajikistan (TJK), Turkmenistan (TKM), Taiwan (TWN), and Uruguay (URY) originated fruits had the highest SSC. The lycopene content varied between 41.37 and 182.82 ㎍/g, 2.81 and 163.72 ㎍/g, and 3.54 and 255.47 ㎍/g using HPLC, UV-Vis spectrophotometer, and microplate reader spectrophotometer, respectively. Red- and pink-fleshed fruits had the highest levels of lycopene content compared to the yellow- and orange-fleshed. Lycopene content had a significant positive correlation with SSC, however, no correlations were detected between lycopene and other quantitative fruit morphological characters. Our study demonstrated high diversity exists in fruit morphological traits and lycopene content of the germplasm collections which provide beneficial baseline data for a future breeding program and utilization of watermelon germplasm collections in gene banks for the maintenance and improvement of the current levels of production, marketability, and health-related benefit of watermelon fruits.

• Journal of Biosystems Engineering
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• 제37권3호
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• pp.177-183
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• 2012

Purpose: In near infrared spectroscopy, interactance configuration of a light source and a spectrometer probe can provide more information regarding fruit internal attributes, compared to reflectance and transmittance configuration. However, there is no through study on the parameters of interactance measurement setup. The objective of this study was to investigate the effect of the parameters on the estimation of soluble solids content (SSC) and firmness of muskmelons. Methods: Melon samples were taken from greenhouses at three different harvesting seasons. The prediction models were developed at three distances of 2, 5, and 8 cm between the light source and the spectrometer probe, three measurement points of 2, 3, and 6 evenly distributed on each sample, and different number of fruit samples for calibration models. The performance of the models was compared. Results: In the test at the three distances, the best results were found at a 5 cm distance. The coefficient of determination ($R_{cv}{^2}$) values of the cross-validation were 0.717 (standard error of prediction, SEP=$1.16^{\circ}Brix$) and 0.504 (SEP=4.31 N) for the estimation of SSC and firmness, respectively. The minimum measurement point required to fully represent the spectral characteristics of each fruit sample was 3. The highest $R_{cv}{^2}$ values were 0.736 (SEP=$0.87^{\circ}Brix$) and 0.644 (SEP=4.16 N) for the estimation of SSC and firmness, respectively. The performance of the models began to be saturated when 60 fruit samples were used for developing calibration models. The highest $R_{cv}{^2}$ of 0.713 (SEP=$0.88^{\circ}Brix$) and 0.750 (SEP=3.30 N) for the estimation of SSC and firmness, respectively, were achieved. Conclusions: The performance of the prediction models was quite different according to the condition of interactance measurement setup. In designing a fruit grading machine with interactance configuration, the parameters for interactance measurement setup should be chosen carefully.

• 원예과학기술지
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• 제17권3호
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• pp.341-343
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• 1999

기기적인 분석 방법과 관능검사에 의해 '신고' 배 과실의 품질을 조사하여 저장력 판정의 기준을 정하고자 하였다. 상온저장고 및 $2^{\circ}C$ 저온저장고에 저장한 과실을 주요 품질 요인인 당함량과 경도에 따라 구분한 후 각각의 요인에 따른 식미인지도를 조사하였다. 저장 방식별 저장 가능기간은 식미인지도에 근거한 당함량과 경도의 변화 정도를 조사하여 설정하였다. 수확 60일 후 '신고' 배 과실을 이용하여 식미인지도를 조사한 결과, 경도의 경우 $3.3kg/8mm{\emptyset}$ 이상을 보이는 과실이 적정 식미를 보이는 것으로 평가되었고 당함량의 경우에는 13.0% 이상일 때 식미에 적합한 수준으로 평가되었다. 그러나 당함량은 저장중 지속적인 증가 경향을 보임으로써 저장기간 설정의 기준으로는 부적합한 요인으로 판정되었다. 과실의 경도를 기준으로 볼 때, 적정 식미를 유지하는 '신고' 배의 저장가능 기간은 상온저장이 30일, $2^{\circ}C$에서의 저온 저장은 120일 정도인 것으로 평가되었다.