• The Korean Journal of Mycology
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• v.21 no.2
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• pp.106-111
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• 1993

Pectolytic enzymes were extracted in apple fruits rotted by Botryosphaeria dothidea, and their activities and change of pectic substances were investigated. Exo-polygalacturonase(exo-PG), exo-polymethylgalacturonase(exe-PMG), polygalacturonate-trans-eliminase(PGTE) and pectin-methyl-trans-eliminase(PMTE) were produced by the pathogen. Activities of exo-PG and exe-PMG extracted from rotten apple fruits were high to 21.15 and 24.65 units/mg protein in specific activity at seven days after inoculation, respectively. Activities of PGTE and PMTE showed 5.60 and 7.90 units/mg protein, respectively, but they were lower than those of the exo-type enzymes. Water-soluble and versene-soluble pectins were 11.50 mg/100 mg-AIS and 7.31 mg/100 mg-AIS at 14 days after inoculation, namely, they were increased by 4.23 and 2.16 mg/100 mg-AIS over those of sound apples, respectively. Total soluble pectic substances of rotten apple were 72.4% of total pectic substances and it was higher by 24.8% than sound apple. Insoluble pectic substance was notably decreased from 15.32 to 7.16 mg/100 mg-AIS according to progress of decay while total pectic substances were not changed remarkably.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.2
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• pp.143-150
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• 1990

The changesin hardness activities of pectinestrase and polygaacturonase and amounts of pectic substances of cucumber during salting at 1$0^{\circ}C$ were investigated, The hardness of the cucumber was decreased dramatically after 3 weeks whereas activities of pectinestrase and polygalacturonase were increased until 3 weeks and 2 weeks respectively and then decrea-sed. The level of alcohol insoluble solid and protopectin in the cucumber were decreased but those of pectic acid and water soluble pectin were increased during the whole salting periods, Protopectin fractionated from alcohol insoluble solid during salting of cucumber was separated using Sephacryl S-500 It showed that high average molecular weight(AMW) of 100,000 was decreased however lower molecular weight compounds was increased. Pectic acid was observed to be decomposed from AMW 200,000 to AMW 500,000 Water soluble pectin from fresh cucumber contained higher level of pentose with peak I of AMW 2,000,000, however after 6 weeks of saltinf peak II which represented AMW 100,000 was separated. From the changes of sugar composition, the phenomena of softness during the salting was probably caused by solubilization of hemicellulose associated with pectin and decomposition of pectic substances.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.242-246
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• 1995

This paper was carried out to investigate changes in cell wall, cell wall polysaccharides, pectic substances extracted from cell wall of persimmon fruits treated with polygalacturonase and $\beta$-galactosidase in vitro. Degrading degree of cell wall treated with cell wall-degrading enzymes were higher in order polygalacturonase, polygalacturonase+$\beta$-galactosidase and $\beta$-galactosidase. Contents of soluble pectic substances in cell wall treated with cell wall-degrading enzymes showed as the same order as degrading degree of cell wall, while contents of insoluble pectin lower. Contents of versene-soluble pectin and total pectic substance were not affected by cell wall-degrading enzymes. Contents of uronic acid and hexose in soluble material isolated from cell wall treated with polygalacturonase and mixed enzyme were higher than those of untreatment and $\beta$-galactosidase treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1041-1046
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• 1998

This study was carried out to investigate the changes and composition of the non-cellulosic neutral sugars in cell wall of soybean sprouts during growth. The composition of non-cellulosic neutral sugars in cell of soybean sprouts was rhamnose, fucose, xylose, arabinose, mannose, galactose and glucose. The galactose content of cell wall was higher than other non-cellulosic neutral sugars, and was remarkably decreased during growth. The major non-cellulosic sugars of pectic substances were rhamnose, arabinose, and galactose. The arabinose content of pectic substance was increased in cotyledon and hypocotyl during growth. The contents of non-cellulosic neutral sugars were decreased in hypocotyl during growth. The galactose content of pectic substance was higher in cotyledon than those in hypocotyl, and was increased in cotyledon. The content of rhamnose was higher in ionically associated pectic substance than that in covalently bounded pectic substance. The major non-cellulosic neutral sugars of hemicellulose were glucose, rhamnose, arabinose and galactose. The galactose of hemicellulose was decreased remarkably during growth.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.421-425
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• 1985

The changes of pectic substances during baking at $175{\sim}180^{\circ}C$ for 30 minutes and polygalacturonase activities of three sweet potato cultivars on textural properties were investigated. The three different types of sweet potato cultivars were the dry type (Wonki), the intermediate type (Shinmi), and the moist type (Chunmi). The moisture content, alcohol insoluble solid content, composition of pectic substances and hardness were determined before and after baking. It was found that HCl-soluble pectin was significantly changed into water soluble and sodium hexametaphosphate soluble pectin by baking. The dry type, Wonki showed the lowest moisture content, but the highest alcohol insoluble solid content and hardness. Wonki, whose polygalacturonase activity was the highest, had the highest HCl-soluble pectin content after backing.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.149-154
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• 2003

Changes in mineral (Ca, Mg) contents and pectic substances of mature-green 'Nanko' Mume fruits hermetically packaged in 0.03 mm low density polyethylene (LDPE) films with and without gas absorbents were examined during storage at $25^{\circ}C$ for 10 days. Each packaging contained 10 g $Ca(OH)_2$ as a carbon dioxide scavenger, 30 g $KMnO_4$ as an ethylene scrubber or their mixture. In the presence of the ethylene scrubber, losses in mineral contents of alcohol insoluble solids and water soluble pectin were remarkably suppressed, whereas no significant difference was observed in the Ca content between the fresh fruit and those stored for 10 days. Fruits packaged with the ethylene absorbent retained higher amount of pectic substances than those with other packaging treatments. Degradation of the pectic substances into small molecules was also noticeably reduced when the ethylene scrubber was used. Overall results showed that the combination of the gas permeable film and the ethylene absorbent could be applied to mature-green Mume fruits as an effective packaging method to retard the texture softening during storage at the ambient temperature.

• Korean journal of food and cookery science
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• v.5 no.1
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• pp.43-47
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• 1989

For identifying the cause of the difference from the texture of mealy potatoes-Namjak and soomi- and soggy Potatoes-Daeji and Dowon-, starch and pectic substances and their relating materials were analyzed, and polygalacturonase(PG) activity was measured. The shape and size of Namjak and soomi starch granules were circular and diameter ranged from 0.02 to 0.024 mm. In the meanwhile, Daeji and Dowon had two sizes of starch granules; larger one tend to be oval in shape and diameter of longer side ranged from 0.04 to 0.045 mm, that of narrower side ranged from 0.02 to 0.03 mm and smaller one was rather circular in shape and average deameter was below 0.005 mm. Oval shaped potato starch grancules under polarized light showed dark cross of V-shape, whereas circular granules showed cross shape. Total sharch contents of Namjak and soomi were higher than that of Daeji and Dowon. The changes of pectic substances were the decrease of the insoluble pectin and the increase of the soluble pectin, and the reduction of the total pectic substance content after cooking. This phenomena were more prominent in Namjak and Soomi than in Daeji and Sowon. PG activities of Namjak and Soomi were greater than Daeji and Dowon. Calcium contents of Namjak and Soomi were lower than Daeji and Dowon. Phytic acid contents of Namjak, Soomi, Daeji and Dowon were 0.093%, 0.096%, 0.078%, and 0.081%, respectively. Hardness of Namjak and Soomi were less than Daeji and Dowon. The mealy potatoes had higher starch contents, higher tendency to pectin solubilization, higher PG activities, lower calcium contents and less hardness than the soggy Potatoes.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.17 no.2
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• pp.27-38
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• 2006

The contents and physicochemical properties of fiber in 15 kinds of vegetables being consumed commoly in Korea were investigated, and the effects of various cooking and Kimchi fermentation) on fiber were studied. Contents of total pechin in raw vegetables were 0.89-2.75g/100g, and most were 1-2g/100g, on dry weight basis. Considering each fraction of pectic substances, the content of HWSP of vegetables ranged in 0.33-0.98g/100g, HXSP, 0.29-0.81g/100g and HCLSP, 0.30-1.40g/100g. HCLSP of three pectic fractions showed the greatest variation according to the kinds of vegetables. Every vegetables showed similar contents of three pectic fraction. Cooking decreased total pectin content in all vegetables regardless of cooking methods and the greatest reduction was observed in boiling. Among three pectic fractions, hot water soluble pectin(HWSP) increased, and sodium hexamtaphosphate soluble pectin(HXSP) and HCL soluble pectin(HCLSP) decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.1
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• pp.63-68
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• 1988

The changes of methoxy content. compositional sugars. degree of esterification (DE) and pectic substances such as LMP (low methoxy pectin), HMP (high methoxy pectin) IAP (ionically associated pectin) and CBP (covalently bounded pectin) of Fuji apple were investigated during maturity. The contents of LMP+HMP and IAP+CBP in alcohol insoluble solid(AIS) were 70% and 20%. respectively. These pectic substances were increased slightly during maturity. The reductions of hexose and uronic acid were Iron 20-50% and from 2-4%, respectively, but the inclosed of pentose was from 1-9% in LMP, HMP, IAP and CBP during maturity of Fuji apple. The galactose was decreased significantly among hexose. Whereas the relative ratio of uronic acid in HMP and CBP was increased.

• Korean journal of food and cookery science
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• v.4 no.1
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• pp.59-63
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• 1988

The changes of acidity, the content of alcohol-insoluble solid (AIS) and pectic substances of Kimchis which were prepared with various garlic contents and fermentation at $21^{\circ}C$ were investigated. Acidity and the content of water soluble pectin of Kimchis increased but the content of AIS and protopectin decreased during the fermentation. As the Kimchis contained high garlic contents compared with the Kimchis deleted garlic, acidity of those rapidly increased but the content of AIS of those slightly decreased with fermentation. In the case of Kimcltis contained high garlic contents, protopectin decreased and water soluble pectin increased with fermentation, but the amount of changes was small.