• Food Science and Biotechnology
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• v.18 no.4
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• pp.878-883
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• 2009

In Brazil canned 'Biuti' peach is a very popular form of this sub-tropical fruit. This production represents an important economic agro-activity in Minas Gerais, Brazil during the summer period, in preparation for the Christmas celebrations. The aim of this work was to characterize the 'Biuti' peach polyphenoloxidase (PPO), since peach products show enzymatic oxidation of the polyphenols by oxidative enzymes, which affects the products during their shelf life. Two different hypothesis for the browning problem in processed peaches were studied: the inadequacy of the blanching treatment and the presence of a latent phenolase in the peaches. The PPO was characterized: pH optimum (5.5) and stability (5.5-6.5); optimum temperature at $20^{\circ}C$ and 80% of the activity retained after 30 min at $15-40^{\circ}C$. The test for the presence of latent PPO in the processed and canned peaches was negative. Ascorbic acid, ${\beta}$-mercaptoethanol, sodium metabisulfite, and cysteine were efficient in inhibiting the PPO.

• Journal of Biosystems Engineering
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• v.27 no.3
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• pp.227-234
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• 2002

This study was conducted to nondestructively estimate the volumetric information of peach and pit and to visualize the 3D information of internal structure from magnetic resonance imaging(MRI) data. Bruker Biospec 7T spectrometer operating at a proton reosonant frequency of 300 MHz was used for acquisition of MRI data of peach. Image processing algorithms and visualization techniques were implemented by using MATLAB (Mathworks) and Visualization Toolkit(Kitware), respectively. Thresholding algorithm and Kohonen's self organizing map(SOM) were applied to MRI data fur region segmentation. Volumetric information were estimated from segemented images and compared to the actual measurements. The average prediction errors of peach and pit volumes were 4.5%, 26.1%, respectively for the thresholding algorithm. and were 2.1%, 19.9%. respectively for the SOM. Although we couldn't get the statistically meaningful results with the limited number of samples, the average prediction errors were lower when the region segmentation was done by SOM rather than thresholding. The 3D visualization techniques such as isosurface construction and volume rendering were successfully implemented, by which we could nondestructively obtain the useful information of internal structures of peach.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.80-83
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• 2008

Anthracnose symptoms were frequently observed on fruits of peach trees grown in Yeongi in Korea during disease survey in August from 2000 to 2005. The disease incidence was as high as 40% at its maximum in the orchards investigated. A total of 24 isolates of Colletotrichum species were obtained from the anthracnose symptoms, out of which 20 were identified as Colletotrichum gloeosporioides and the four remaining ones as C. acutatum based on their morphological and cultural characteristics. Two isolates of each C. gloeosporioides and C. acutatum caused anthracnose symptoms on the fruits by both wound and unwound inoculation, which were similar to those observed in the orchard. The symptoms appeared more rapidly by the wound inoculation than by the unwound inoculation. There was no difference in pathogenicity between the C. gloeosporioides and C. acutatum isolates tested. In Korea, only C. gloeosporioides has been recorded as the causal fungus of anthracnose of peach tree. This is the first report that C. acutatum also causes anthracnose of peach tree in Korea.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.115-118
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• 1999

A new bacterial disease was found on trees of peach(Prunus persica var. vulgaris Max) at Kumho Kyungbuk in April 1999. The disease usually occured on over wintered buds branchs and stems of the Cheon-Hong cultivar. The buds died without sprouting and the branches showed entire wilting Droplets of bacterial ooze was occasionally running down the surface of diseased plants under moist condition. Artificial needle prick inoculation with isolates obtained from branchs of naturally infected plants produced symptoms similar to those occuring under natural condition. On the basis of bacteriological characteristics and pathogenicity on the host plant of the organism the causal bacterium was identified as Xanthomonas arboricora pv. pruni and this disease was proposed to name "Bacterial branch blight of the peach tree"

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.165.1-165
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• 2003

복숭아는 절단 후 표면의 갈변현상이나 당도 저하 등이 발생하여 신선편이 식품화시 품질열화의 원인이 된다. 이에 본 실험에서는 일차적으로 유명 품종에 한해 fresh-cut peach의 anti-browning chemicals를 탐색하고, 그 결과를 통해 이차적으로 효과가 우수한 chemicals를 선정하여 백향 품종에 농도별 실험을 행하였다. 유명 품종을 반으로 절단한 후 제핵하고 8등분하여 1% ascorbic acid, 1% sodium chloride, 1% sodium ascorbate monohydrate, 0.005% 4-hexylresorcinol 용액에 3분간 침지시켜 draining한 후, PP tray에 담고 PP film으로 밀봉하여 4$^{\circ}C$에서 저장하였다. 가용성고형분은 to sodium chloride 용액으로 처리한 구에서 가장 높게 유지되었고 pH 또한 비교적 일정하였으며, 1% sodium chloride과 1% sodium ascorbate monohydrate 용액으로 처리한 구의 L값이 높게 유지되었다. 따라서 fresh-cut peach에 효과가 있는 것으로 판단되는 이 두 chemicals의 농도별 용액을 조제하여 같은 방법으로 백향 품종의 갈변저해제로서 처리하였다. 그 결과 2% sodium chloride의 가용성고형분이 가장 높게 유지되었으며 2% sodium ascorbate monohydrate 다음으로 2% sodium chloride 용액 처리구의 L값의 변화 양상이 가장 양호한 것으로 나타났다. 따라서 종합적으로 살펴볼 때, 2% sodium chloride 용액의 처리가 fresh-cut peach의 품질 변화 억제에 적합하다고 판단되었다.

• Journal of the Korean Chemical Society
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• v.64 no.6
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• pp.443-446
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• 2020

• Journal of the East Asian Society of Dietary Life
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• v.22 no.5
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• pp.649-656
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• 2012

We investigated the quality characteristics of dohwaju (fermented with peach flowers and branches, a Korean traditional alcoholic beverage) containing different sub-ingredients. During fermentation, the inner temperatures of the added sub-ingredient treatments were higher compared to non-treatment, and only peach branches treatment. showed the highest inner temperature. There were no significant differences in the physicochemical results among the treatments. pH decreased from the first mashing day to the second and then increased slightly until fermentation was terminated. Total acidities showed opposite patterns as compared to pH level. Amino acid contents, soluble solids, and alcohol contents increased steadily until the end of fermentation, whereas reducing sugar contents showed the opposite trend. In a preference survey, DB (only peach branches)-treated dowhaju showed the highest evaluation in terms of taste and overall acceptability with walues of $5.07{\pm}1.38$ and $5.57{\pm}1.16$, respectively. Based on the results of this study, we concluded that only peach branches treatment is optimal for the manufacture of dowhaju. We expect that the quality of dowhaju can be improved by providing basic information concerning its manufacture.

• Applied Microscopy
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• v.43 no.1
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• pp.21-26
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• 2013

The oriental fruit moth (Grapholita molesta Busck) and the peach fruit moth (Carposina sasakii Matsumura) are the most severe insect pests affecting apple orchards in Korea. To prevent an outbreak of these two species and to control these agricultural insect pests, it is important to identify them accurately. However, it is hard to classify them when they were in the larval stage since they tunnel into the apple fruit. In this study, surface structures of the two species of larvae were observed using stereo microscope and scanning electron microscope. Distinct differences between the two species of larvae were found. The prothorax spiracles of oriental fruit moth larvae were approximately twice as large as those of peach fruit moth larvae. The arrangements of subventral setae, located around the proleg, were different between oriental fruit moth and peach fruit moth larvae. Furthermore, subdorsal setae of oriental fruit moth were located next to the spiracle on the 8th abdominal segment, while that of peach fruit moth was located above the spiracle. The identification of the two species of larvae observed in this study was confirmed using polymerase chain reaction-restriction fragment length polymorphism method. Surface structural differences are intrinsic characteristics for each species of larvae and can easily be identified using stereo microscope. These specificities will be helpful where a large number of field-collected larvae need to be identified routinely in pest control research.

• Journal of Biosystems Engineering
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• v.34 no.6
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• pp.446-453
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• 2009

This study was conducted to find condition of improving the quality of peach by using surfacing washing system. The rate of weight loss of A,B groups were showed slower decreasing trend than CT group and the value of soluble solid degree was not different significantly among all groups from the results of stored peach treat with surface washing system of peach in the first experiment. The colory value of surface were increased with increasing storage period in all treatments. Browning pace of A,B groups were slower than control. Emission of carbon dioxide was increased from the results of respiration rate, 6-10 mL/kg/hr $(10^{\circ}C)$ and 32-41 mL/kg/hr $(25^{\circ}C)$. In second experiment with surface washing system of peach, the value of soluble solid was showed with similar value from 10 $Brix^{\circ}$ to 13 $Brix^{\circ}$. The pace of soft rot of EW groups were lower than CT groups from the results of hardness during storage period. The results of colory value was not showed with significant difference in $15^{\circ}C$ and $20^{\circ}C$ storage temperature but changed to browning in EW groups. The moisture contents was from 85% to 90% in all groups. And the count of total microorganism of EW groups were lower than control. Also total coliform of EW groups were negative. In sensory evaluation, washing peach was showed higher value with significant difference in all acceptability.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.737-754
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• 2019

Peaches have soft tissues compared to other fruits and are vulnerable to softness, wounds, and loss of marketability due to the weak fruit hardness after harvest. It is necessary to develop a technology to improve the shelf-life of the fruit to expand the distribution of peaches. Calcium compounds and chitosan have an important role in improving the shelf-life of fruit by maintaining the hardness and reducing the respiration rate in peach fruits. In this study, to select useful compounds to improve the shelf-life of peaches, calcium citrate, calcium chloride, calcium nitrate, GH-Ca, OS-Ca, chitosan, and chitosan dissolved in calcium chloride were sprayed onto peach trees. The characteristics of the harvested fruits were investigated after the 'Kumhong' and 'Madoka' peach tree treatments. The hardness of the fruit was kept the highest with the combined treatment and remained high with the calcium citrate, chitosan and calcium nitrate treatments. Ethylene production and respiration were effectively inhibited by the GH-Ca and chitosan treatments. There was no significant difference in soluble solids content and acidity among the fruits treated with the chemicals. The coloration of the fruit skin was not delayed by the calcium and chitosan chemical treatments. Calcium compounds were increased in the fruits and leaves of the peach trees treated with the chemicals compared to the untreated ones. These results suggest that the calcium treatment extended the shelf-life by increasing the calcium content in the leaves and fruits of the peach trees.