• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.443-450
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• 1984

Chemical and microbial changes during Kimchi (a group of Korean seasoned pickles) fermentation were carried out at various temperatures and salt concentrations. The time reaching optimum ripening of Kimchi varied depending upon fermentation temperature and salt concentration. At high temperature and low salt content Kimchi fermentation was faster than at low temperature and high salt content. The ratio of volatile to non-volatile acids reached its maximum at the optimum ripening time of Kimchi and decreased thereafter. Leu. mesenteroids, Lac. brevis, Lac. plantarum, Ped. cerevisiae, Str. faecalis and low acid producing Lactobacilli were isolated from Kimchi samples. However, the main microorganism responsible for Kimchi fermentation was Leu. mesenteroides and Lac. plantarum was the main acidifying organism. Total viable count increased rapidly in the beginning of fermentation and reached its maximum number at optimum ripening time and then decreased slowly as the acidity of Kimchi increased. While the total aerobic bacteria and fungi decreased during Kimchi fermentation, the yeast increased significantly at lower temperature.

• Proceedings of the Korean Society of Crop Science Conference
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• 1986.06a
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• pp.24-25
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• 1986

• Journal of agriculture & life science
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• v.44 no.1
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• pp.1-8
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• 2010

This study was conducted to investigate effect of low temperature and ripeness stages on fruit quality of chilli pepper (cv. Nockgwang) during storage at 5, 7, and $10^{\circ}C$. Fruits at three ripeness stages were selected based on uniform fruit size and three maturities on peel color: S1 (fully developed fruit just before the onset of ripening), S2 (fruits in the onset of color change), and S3 (fruits in completely red in color). Lower temperature attributed to increase fruit weight loss (WL) and WL was higher in S2 than the other ripeness stages. The highest respiration rate and ethylene production was found at S2 fruit while those of fruit in green and red showed similar and remained lower level during storage. Electrolyte leakage (EL) was higher as storage temperature decreased. After 28 d storage, EL rates of fruits at $5^{\circ}C$ were 43, 36, and 17% in S1, S2, and S3 while those at $10^{\circ}C$ were 17, 19, and 14%, respectively. These results show that chilli pepper fruits are tended to lose more water at lower temperature partially associated with increased EL. Thus, threshold storage temperature must be considered for avoiding chilling during storage and for extending the storage life of fresh pepper fruits.

• Applied Biological Chemistry
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• v.14 no.1
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• pp.29-34
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• 1971

Changes in hot-taste component during the after-ripening period of hot pepper fruit were surveyed and summarized as follows; (1) Capsaicinoid contents were steadily increased as the after-ripening proceeded when physiological activity of the sample was suppressed during each stage of the ripening with the vacuum dry freezing. (2) It was assumed by determining phenylalanine contents and activities of phenylalanine ammonialyase to see synthetical process of capsaicin in the metabolic part of vanillylamine that there is a gradual synthesis and accumulation of capsaicin during the after-ripening period. (3) Lignin-like substances, as in the case of capsaicinoid, showed a steady increase during the after-ripening period. (4) The contents of polyphenolic compounds and polyphenol oxidase activity were higher with low temperature treatment.

• Preventive Nutrition and Food Science
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• v.21 no.3
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• pp.289-295
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• 2016

Curcumin is a flavonoid found in the rhizome of the turmeric plant (Curcuma longa L.) and has recently attracted interest because it has numerous biological functions and therapeutic properties. In the present study, we attempted to incorporate curcumin into medium-chain triglyceride (MCT) nanoemulsions (0.15 wt% curcumin, 10 wt% MCT oil, and 10 wt% emulsifiers) with various emulsifiers [polyoxyethylene (20) sorbitan monolaurate (Tween-20), sorbitan monooleate (SM), and soy lecithin (SL)]. The physicochemical properties of the nanoemulsions including the Ostwald ripening stability were investigated. The initial droplet size was found to be 89.08 nm for the nanoemulsion with 10 wt% Tween-20 (control), and when Tween-20 was partially replaced with SM and SL, the size decreased: 73.43 nm with 4 wt% SM+6 wt% Tween-20 and 67.68 nm with 4 wt% SL+6 wt% Tween-20 (prepared at 15,000 psi). When the nanoemulsions were stored for 28 days at room temperature, the droplet size increased as the storage time increased. The largest increase was observed for the control nanoemulsion, followed by the 4 wt% SL+6 wt% Tween-20 and 4 wt% SM+6 wt% Tween-20 systems. The Turbiscan dispersion stability results strongly supported the relationship between droplet size and storage time. The time-dependent increase in droplet size was attributed to the Ostwald ripening phenomenon. Thus, the Ostwald ripening stability of curcumin-loaded MCT nanoemulsions with Tween-20 was considerably improved by partially replacing the Tween-20 with SM or SL. In addition, curcumin may have acted as an Ostwald ripening inhibitor.

• Journal of Ocean Engineering and Technology
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• v.14 no.1
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• pp.37-43
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• 2000

$PbTiO_3$ was prepared by addition of lead-tltanium mixed aqueous solution to an ethanol solution of oxalic acid. The influence of various ripening factors was invesigated. On the basis of the results in the mono-component system we studied the foramtion of $PbTiO_3$ phase with various ripening conditions. The $PbTiO_3$ phase formation was accelerated with the ripening time temperature and ultrasonic irradiation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.2
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• pp.63-69
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• 2019

Black-colored rice contains anthocyanin, which has an antioxidant function on the seed coat. Anthocyanin content is greatly affected by the cultivation environment, especially the average temperature during the ripening stage. Generally, low temperatures during the ripening stage increase anthocyanin content. To control the average temperature during ripening stage in the field, transplanting time has to be regulated. In this study, anthocyanin content variation was examined in relation to the transplanting time and the average temperature during the ripening stage. For the study, fourteen black-colored rice cultivars with different maturity types (four of early-maturing, five of medium-maturing, and five of medium-late maturing) were selected. The transplanting times used were May 20, June 5, June 20, and June 30. The field experiment was conducted in the Miryang, Kyoungsangnamdo province, Korea from 2014 to 2017. The anthocyanin content in all cultivars was higher when the transplanting time was delayed, and the highest anthocyanin content was observed in the transplanting on June 30. Variation in anthocyanin content according to the change in transplanting time is the greatest in the early maturing cultivars. The least change was observed in medium maturing cultivars. Regression analysis showed a significant correlation between temperature and anthocyanin content, but the degree of correlation was very low in the medium maturing cultivar. As a result, the optimal average temperature during the grain filling stage for increasing the anthocyanin content of black colored rice was $22{\sim}23^{\circ}C$. The rice yield increased in plants transplanted until June 20 and decreased thereafter owing to low temperature during the grain filling stage. The anthocyanin content increased with delaying the transplanting time up to June 30 but the rice yield decreased after June 20. Nevertheless, the rate of increase in anthocyanin content was higher than the rate of decrease in rice yield. As a result, the optimum transplanting time and an average temperature of grain filling stage for black-colored rice variety were June 30 and $23{\sim}24^{\circ}C$ considering both anthocyanin content and rice yield.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.190-201
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• 1980

This experiment was designed to optimize the process of manufacturing the soybean cheeses and to elucidate the chemical changes during ripening when the chemical changes during ripening when the milk components and enzyme preparations were added to the raw materials. Conditions for extracting soybean protein such as temperature, duration and amount of water added were determined; various coagulaters were compared by checking the curd texture and yield; starters from S. thermophilus, S. lactis MLB and S. cremoris EB-9 were tested as single- or multi-stain combinations; and the effects of skim milk and/or rennins-both microbial and calf origin-addition upon the process of manufacturing and ripening were studied. The results obtained were as follows. 1. optimal conditions for soybean extraction were found to be: temperature $100^{\circ}C$, duration 10 minutes, and amount of water added 9-fold, as considered the extraction rate of solids and proteins, and curd yield. 2. Sodium gluconate was the most effective among the coagulators tested, and 5% of single-strain starter from S. thermophilus was appered to be adequate inoculum for curd formation. 3. The effects of skim milk and/or rennins addition on the process of manufacturing and ripening of soybean cheeses were: 1) The addition of rennins resulted in fast formation of curd, especially with skim milk it was so. And Hansen rennet extracts brought better results in curd formation than Meito rennet extracts did. 2) No significant effect was observed on the changes in moisture content during ripening, however the levels of moisture contents in the products were higher in case of using Meito rennet extracts. 3) Effect on pH changes during ripening was also not significant in general, while levels of pH were decrease markedly during manufacturing and the initial stage of ripening. 4) The levels of bacterial counts were much higher in case of skim milk addition throughtout the ripening period. In general the numbers were reached to approximately $10^8cells/g$ during manufacturing, then decreased gradually to below $10^2cells/g$ in 8 weeks of ripening. 5) The addition of skim milk and/or rennin resulted in higher ripening index, and skim milk plus Meito rennet extracts was appeared to be best combination for the ripening index.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.229-234
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• 1982

Environmental factors are known in general to influence much on the development of abscission layer and thereby on shedding of plant parts. The present study was carried out to determine the effect of meterological condition during ripening on the grain shatterability of rice plants at harvest. Different meteorological conditions were obtained by shifting transplanting timing of 40 days old rice seedlings 4 times with a 15 days-interval. Grain shatterability was measured as tensile strength of rice grains: it varied within a range of 214g. to 251g. in a practically non-shattering Japonica variety'Jinheung' and l27.5g. to 204g. in an easy shattering Indica \times Japonica progeny variety'Taeback'. In view of field loss of rice, the variation in tensile strength with time of transplanting and harvest did not matter in Jinheung, but was an important factor in Taeback. In Taeback the tensile strength was significantly correlated positively with mean, maximum and minimum air temperature and relative humidity during a certain period of grain ripening, especially during 30 days period before harvest, but diurnal range of air temperature showed a significant, negative correlation with it. The tensile strength seemed to be more closely related with min. air temperature than max. air temperature, and it was not significantly correlated with radiation amount during any period of pre-harvest. Meteorological effect on grain shatterability may vary with variety, but temperature regime during ripening appears to play major role among the meteorological factors in easy shattering and more thermophilic Indica \times Japonica varieties: lower the temperature, greater the shatterability.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1091-1095
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• 2009

The aim of this study investigated the fluctuations of 3 characters from 3 ecotypes [early ripening (ER), middle ripening (MR), and late ripening (LR)] of 20 Korean brown rice cultivars in different storage systems [time: 12 and 24 weeks, temperature: low ($10^{\circ}C$) and room ($25^{\circ}C$)]. With increase of storage time and temperature, lipoxygenase activity, and fat acidity increased, whereas germination rate was reduced. ER cultivars exhibited the highest lipoxygenase activity of $35.49{\pm}2.46$ unit/mg protein during 24 weeks storage at $25^{\circ}C$, followed by LR ($32.73{\pm}1.33$) and MR ($32.66{\pm}1.62$) cultivars. The amounts of fat acidity also were observed by the same order (ER: $20.40{\pm}2.12$>LR: $19.68{\pm}1.86$>MR: $19.64{\pm}1.35$ mg KOH/100 g). Germination rate slightly decreased with increase of time and temperature (MR>LR>ER), but MR and LR cultivars showed the most significant changes (ER: $60.90{\pm}23.47%$, MR: $32.66{\pm}13.95%$, and LR: $32.53{\pm}5.87%$). On the basis of above results, MR cultivars were evaluated the highest quality, because high lipoxygenase activity, high fat acidity, and low germination rate have deteriorated in quality and generated off-odor. Thus, MR cultivars might be very important sources in food processing and stored dietary supplement aspects.