• Culinary science and hospitality research
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• v.12 no.4 s.31
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• pp.299-319
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• 2006

The purpose of this study was to investigate the changes of hardness and microstructure of Dongchimi cooked with various sources of sugar(xylitol, xylose, sugar, pear juice). It was fermented at $10^{\circ}C$ for 60 days. The changes of pH in Dongchimi used different kinds of sugar decreased in all samples during the fermentation period, and then showed a slow decrease after 12 days of fermentation. The total acidity of Dongchimi using xylitol arrived slowly at the best tasting condition($0.3\sim0.4$ point) compared with other conditions. The changes of salt content were showed high as compared with other test conditions in 0 day, the day of fermentation. At the early stage of fermentation, the changes of turbidity of Dongchimi using sugar, pear juice were showed high as compared with those of Dongchimi using xylitol, xylose for $5\sim15$ days of fermentation. The maximum cutting force of Chinese radish Dongchimi showed the highest value among al at the 25 th day of ripening and then decreased gradually. The maximum cutting force of Dongchimi using sugar showed the lowest. The calcium and magnesium contents of Dongchimi juice and Chinese radish Dongchimi juice using xylitol were observed high at the early stage of fermentation and showed the highest value during the fermentation period. The microstructure showed disintegration appearance of middle lamella and cell wall during the fermentation period.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.453-460
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• 2016

The parentage of the horticulturally important pear cultivar 'Niitaka' was confirmed by determining its S-genotypes based on the S-RNase and $PpSFBB^{-{\gamma}}$ genes, and genotyping using simple sequence repeat (SSR) markers. Previous reports suggested that the cultivars 'Amanogawa' and 'Imamuraaki' were the parents of 'Niitaka', although the cultivars 'Chojuro' and 'Shinchu' were also examined as candidate parents, along with two other cultivars. In the present study, the S-genotype of 'Niitaka' was determined to be $S^3S^9$. The $S^9$-RNase of 'Niitaka' was found to be likely inherited from the parent 'Amanogawa' ($S^1S^9$) and the $S^3$-RNase from 'Chojuro' ($S^3S^5$) or 'Shinchu' ($S^3S^5$). Based on the S-genotypes, the cultivar 'Imamuraaki' ($S^1S^6$) had no contribution to the parentage of 'Niitaka' ($S^3S^9$). A total of 67 polymorphic SSR markers were used to further confirm the parentage of 'Niitaka'. Discrepancies were found at several SSR loci between 'Niitaka' and the cultivars 'Imamuraaki' and 'Shinchu', whereas 'Niitaka' inherited alleles from 'Amanogawa' and 'Chojuro' at all SSR loci. Therefore, our findings established that 'Amanogawa' and 'Chojuro' are the parents of pear cultivar 'Niitaka', and not 'Imamuraaki' as previously reported.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.206-212
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• 2004

Prickly pear extract (PPE) was fermented by Lactobacillus rhamnosus LS at 3$0^{\circ}C$ for 2 days. To improve the physicochemical properties of fermented PPE, it was fortified with food polysaccharides (0.2 %) or seaweed calcium before lactic acid fermentation. The viable cell counts, flow behavior, titratable acidity and color stability of fermented PPE were evaluated during 4 weeks of cold storage. Addition of xanthan gum or glucomannan increased the apparent viscosity and acid production, viable cell counts and red color of PPE were also well maintained during the cold storage. However, fermenting PPE with gellan gum resulted in a decrease in relative absorbance, indicating lower color stability. In particular, PPE fortified with carrageenan or alginic acid showed reduced acid production and lower viable cell counts. Addition of seaweed calcium at a 0.1 % level had positive effects on color stability, and helped maintain viable cell counts of 4.1 ${\times}$ 10$^{9}$ CFU/mL. This study demonstrated that xanthan gum could be used as a good thickening agent and stabilizer for retaining viable cell counts and red color during the cold storage in PPE fermented by lactic acid bacteria.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.10-17
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• 2014

This study was conducted to elucidate the relationship between light and coloring and to obtain basic results for promoting redness expression in 'Kalle' (Pyrus communis L.) pear skin. It was investigated in location of anthocyanin layer by microscopic observation and differences in skin color expression of 'Kalle' bagged with paper bag which has different light transmittance rate and inside temperature. However, there was no anthocyanin layer in the brown skin and golden yellow color, anthocyanin layer was distributed in epidermins or hyperdermis of red skin pear and apple. Dark red colored 'Kalle' had more anthocyanin content, $29.8mg{\cdot}100g^{-1}$ FW than light red colored apple 'Hongro'. Light transmittance rate of physical characteristics used paper bags was the highest in white paper bag, 42.2% and it also had more light quantity, $8.9{\mu}mol$ than any other tested paper bags in specific wave length 650-655 nm. The maximum temperature of inner bag was higher about $3^{\circ}C$ in yellow paper bag. The red coloration and anthocyanin contents in no bagged fruits were higher than in any other bagged fruit. However, red color expression among the bagged fruits was higher in white paper bag than in double layered black paper bag and yellow paper bag. Also, chromaticity value seemd to be a good index to explain variation of fruit skin color, because anthocyanin content and chromaticity value were higher. Based on these results, it is desirable to cultivate 'Kalle' without bag for stable redness expression but bagging is essential for decreasing damage by insect in Korea. Further examination to find suitable time of removing paperbag for redness expression and decreasing insect damage. In addition, it is required to develop paperbag whose transmittance rate is high in specific light wavelength or temperature of inner bags is low. Additional key words: anthocyanin, bagging, chromaticity value, light transmittance, Pyrus communis L.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.591-597
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• 2015

We determined the total C and N stocks in trees and soils after 1 year of fertilization in an experimental orchard with 16-year-old 'Niitaka' pear (Pyrus pyrifolia Nakai cv. Niitaka) trees planted at $5.0m{\times}3.0m$ spacing on a Tatura trellis system. Pear trees were fertilized at the rate of 200 kg N, 130 kg P and $180kg\;K\;ha^{-1}$. At the sampling time (August 2013), trees were uprooted, separated into six fractions [trunk, main branches, lateral branches (including shoots), leaves, fruit, and roots] and analyzed for their total C and N concentrations and dry masses. Soil samples were collected from 0 to 0.6 m in 0.1 m intervals at 0.5 m from the trunk, air-dried, passed through a 2-mm sieve, and analyzed for total C and N concentrations. Undisturbed soil core samples were also taken to determine the bulk density. Dry mass per tree was 5.6 kg for trunk, 12.0 kg f or m ain branches, 15.7 kg for lateral branches, 5.7 kg for leaves, 9.8 kg for fruits, and 10.5 kg for roots. Total amounts of C and N per tree were respectively 2.6 and 0.02 kg for trunk, 5.5 and 0.04 kg for main branches, 7.2 and 0.07 kg for lateral branches, 2.6 and 0.11 kg for leaves, 4.0 and 0.03 kg for fruit, and 4.8 and 0.05 kg for roots. Carbon and N stocks stored in the soil per hectare were 155.7 and 14.0 Mg, respectively, while those contained in pear trees were 17.8 and $0.2Mg{\cdot}ha^{-1}$ based on a tree density of 667 trees/ha. Overall, C and N stocks per hectare stored in the pear orchard were 173.6 and 14.2 Mg, respectively. Compared with results obtained in 2012, the amounts of C stocks have increased by $17.7Mg{\cdot}ha^{-1}$, while those of N stocks remained virtually unchanged ($0.66Mg{\cdot}ha^{-1}$).

• Proceedings of the Culinary Society of Korean Academy Conference
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• 2004.04a
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• pp.21-49
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• 2004

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2001.02a
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• pp.286-291
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• 2001

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.02a
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• pp.309-316
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• 2000

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.557-564
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• 2013

We isolated and identified antioxidants from acidic and neutral ethyl acetate fractions of the peel of pear (Pyrus pyrifolia N. cv. Chuhwangbae). We isolated 4 compounds from the methanol extract, by using 3 different types of column chromatography (Sephadex LH-20, silica gel, and octadecylsilane) and preparative HPLC. We identified the isolated compounds as (S)-(+)-2-cis-abscisic acid O-${\beta}$-D-glucopyranosyl ester (compound 1), 1-[4-O-${\beta}$-D-glucopyranosyl]phenyl ethanone (picroside, compound 2), ${\beta}$-sitosterol (compound 3), and ${\beta}$-sitosteryl 3-O-${\beta}$-D-glucopyranoside (compound 4) by nuclear magnetic resonance analysis. We are the first to report the identification of compounds 1, 2, and 4 from pear.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.448-453
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• 2013

We investigated the occurrence of major pests, 4 species of moths (Grapholita dimorpha Busck, Carposina sasakii Matsumura, Archips breviplicanus Walsingham, Adoxophyes orana Fischer von Roslerstamm), apple aphid (Aphis spiraecola Patch), two spotted spider mite (Tetranychus urticae Koch) and parasitoids in pear orchard with hairy vetch and cutting weeds in Yesan, Chungnam province during the flowering season and summer depression season of hairy vetch, in 2012 and 2013. The occurrence of 4 species of moths in hairy vetch plot and cutting weeds (major is finger grass, Digitaria sanguinalis, 80%) were little different but in case of apple aphid, the density in hairy vetch plot was just 95 aphids per stem at 20th June but low after then. The density of two spotted spider mite on pear leaf in hairy vetch plot was lower than in cutting weeds plot significantly. The number of parasitoids collected in hairy vetch plot during flowering season (May and June) were 398 and 798 in 2012 and 2013, respectively. The number of parasitoids collected in hairy vetch plot during summer depression season (July and August) were 114 and 172, respectively. But in cutting weeds plot, 9 and 22 in May and June, 8 and 5 in July and August. We didn't know either hairy vetch in pear orchard affected the occurrence of 4 species of moths, apple aphid and two spotted spider mite or not but was acted to be favorable for wasps, the natural enemies on the contrary. The improvement of chemical control systems through the selection of low chemicals to natural enemies with cover and green manure plants would turn effective pest management into a possibility.