• Horticultural Science & Technology
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• v.28 no.4
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• pp.600-608
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• 2010

The quality attributes of tomato fruit ($Lycopersicon$ $Esculentum$ Mill.) to treatments with 1-methylcyclopropene (1-MCP) were studied. Harvested tomato fruit was treated one time at the initiation of storage or once-a-day during storage with $1{\mu}L/L$ 1-MCP at different storage temperatures, 12, 17, and $23^{\circ}C$. The results showed that both lower temperature and duration of 1-MCP treatment played an important role in ripening of tomato fruit. The once-a-day 1-MCP treatment was presented to be very effective in delaying quality changes of tomato fruit. The amount of chlorophyll and lycopene were measured to assess the impact of 1-MCP and temperature treatments on ripening, using a specific extinction coefficient absorbance technique. Storing tomato fruit at $12^{\circ}C$ resulted in a longer ripening period (color change) than tomato fruit stored at $17^{\circ}C$ and $23^{\circ}C$. 1-MCP treatment was very effective in retarding chlorophyll degradation and lycopene formation in the pericarp tissue of the tomato fruit at the different storage temperatures. The 1-MCP treatments affected the total chlorophyll content in different fruit tissues of the pericarp and placenta. Exposure of tomato fruit to 1-MCP gas at $12^{\circ}C$, using the once-a-day treatment, was highly effective in delaying pigment and color change.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.9
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• pp.1198-1204
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• 2007

This study was carried out to find the optimal conditions for the extraction of the effective ingredients based on central composite by monitoring the extraction characteristics of each ingredient with a response surface methodology. The optimal condition for the effective component alliin was extract temperature of $60.86^{\circ}C$, extract time of 3.77 hr, and ethanol concentration of 50.68%, and that for allicin was $65.11^{\circ}C$, 2.79 hr, and 13.62%, respectively, with the maximum extraction of 16.72 mg%. The maximum value of extracted total phenolics was 16.72 mg%, the optimal condition for electron donating ability was $93.35^{\circ}C$, 3.22 hr and 10.38%. The optimal conditions for pH 1.2 and 3.0 nitrite-scavenging ability was extract temperature of $79.77^{\circ}C$ and $76.46^{\circ}C$, extract time of 3.22 hr and 3.31 hr, and the ethanol concentration of 10.38% and 1.12%, respectively. With this optimal condition, the obtained maximum values for nitrite-scavenging activities at pH 1.2 and 3.0 were 94.85% and 63.22%, respectively.

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.321-326
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• 1993

Membrane separation technology with polymeric membranes for the effective separation and energy conservation has emerged to be a new technology for separation in recent years. In this research, the reverse osmosis process was applied to the concentration process of clarified apple juices. The changes of concentration and permeate flux of apple juice in this process were measured at different membrane characteristics, operating pressures, temperature and flow rate. And the changes of quality were also measured at different pressures. The prediction model for the permeate flux based on these data was established. Generally, the osmotic pressure increased as the concentration of the feed increased in the RO process, which caused a reduction of permeate flux. The changes of permeate flux were not much dependent on temperature and flow rate, but very much dependent on pressure. The most effective factor in increased permeate flux was found to be the operating pressure, followed by temperature and flow rate. The final prediction model for the permeate flux was developed by the $SPSS^x$ computer program. The result showed that recovery of sugar was not affected by processing pressures, but the percentage recovery of total flavor was increased with increasing pressure.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.8 s.145
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• pp.1176-1187
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• 2005

The purpose of this study was to evaluate the efficiency of cooling vests developed for farm workers harvesting red pepper in summer. The study was performed using the following two steps: 1) Climatic chamber test, 2) Field test. For the chamber test, a work environment was simulated as $33^{\circ}C$ and $65\%$RH, and the thermo-physiological and subjective responses were measured with and without cooling vests. Twelve young males participated as subjects. For the field test, three farmers participated while harvesting red pepper on the form, in summer. The measurements used were same as in the chamber test. Subjects were tested without any cooling vests, as a control. They were tested wearing vests with 2 frozen gel packs (CV2: Cooling area, $308cm^2$), and vests with 4 frozen gel packs (CV4: Sooting area, $616cm^2$). As a result of the chamber test, rectal temperature($T_{re}$) and mean skin temperature( $T_{sk}$) were lower in both CVs than in Control, and this tendency was statistically significant in CV4 (p<.05). Clothing microclimate temperature ($T_{clo}$) and total sweat rate (TSR) were significantly lower when wearing cooling vests (p<.05) Heart rate (HR) was also lower in wearing cooling vests than in Control, and the speed of recovery to the comfort level was faster when the subjects wore cooling vests. In addition, subjects felt 'less hot, less humid, and less uncomfortable' in both CVs than in Control. Field tests showed a similar tendency with the chamber tests. In particular, wearing the cooling vest was effective in restraining the raise of $T_{clo}$ on the back. It can be concluded that the cooling vest was effective in alleviating heat strain and discomfort in both the chamber test and the field test, despite the cooling area of the cooling vest being just $3.4\%$ of the body surface area ($616cm^2$).

• Journal of Food Hygiene and Safety
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• v.35 no.1
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• pp.60-67
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• 2020

This study determined the microbial contamination levels of hot pepper at harvest, sorting, and distribution stages to suggest a way of reducing the microbial contamination of hot peppers by changing work gloves used throughout these processes. According to the monitoring results, the contamination levels of total aerobic bacteria (TAB) were found in the following order: soil (5.3±0.9 log CFU/g), hot pepper (4.2±0.9 log CFU/g), gloves (4.2±0.6 log CFU/g), baskets (4.1±0.7 log CFU/ g), clippers (3.9±0.6 log CFU/ g) and water (3.2±1.1 log CFU/g) at harvest stage. The contamination level of coliforms were found in the following order: soil (2.2±0.9 log CFU/g), hot pepper (2.2±0.3 log CFU/g), gloves (2.1±0.6 log CFU/g), clippers (2.0±0.21 log CFU/ g) and baskets (1.9±1.1 log CFU/ g) at harvest stage. TAB on hot pepper at the harvest stage was reduced from 4.2±0.9 log CFU/g to cold storage 3.8±0.2 log CFU/g and room temperature storage 2.6±0.3 log CFU/g, respectively. By the replacement of work gloves and lower distribution temperature, TAB levels of the peppers were significantly reduced compared to those without replacement and distributed at room temperature. In addition, the utilization of plasma was effective on reducing microbial contamination of hot pepper. These results demonstrated that appropriate replacement of gloves at the harvest stages, using plasma in the distribution stage, and refrigerated distribution conditions, which are simple and easy to practice in the field, are effective to reduce microbial contamination on hot peppers.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.592-601
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• 1997

The purposes of this study were to develop Hazard Analysis Critical Control Point-based standardized recipe applicable to cook/chilled soy sauceglazed mackerel and to evaluate the qualities related to the product flow of this item. After conducting experimental cooking, preliminary test, and analysis of recipes, critical control points were identified, control methods were determined, and HACCP-based recipe was standardized. At each critical control point, time-temperature profile was recorded and microbiological analysis (total aerobic plate counts, psychrotrophic plate count, coliform, and fecal coliform count), chemical analysis (pH, acid value and volatile based nitrogen (VBN)) and sensory evaluation of the item were done. Time-temperature data showed that the time the menu item had passed through temperature danger zone (5∼60$^{\circ}C$) during all phases was 60 min. At rapid cooling, but after cooling at room temperature, the temperature of this menu item did not drop below the ambient temperature. The results of microbiological test were negative throughout all phases following cooking and the results of chemical analysis did not change significantly in terms of storage periods except for VBN which increased on 7th day significantly(p<0.05). After steam/convection oven reheating and microwave oven reheating, the sensory score of the only appearance decreased significantly related to the storage time of overall quality profiles. But significant differences were not detected according to two reheating methods. In conclusion, this HACCP-based recipe was considered as an effective tool for assuring microbial as well as sensory quality of this cook/chilled item.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.203-209
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• 2001

Development and reproduction of the sweetpotato whitefly, Bemisia tabaci(B biotype) were investigated under different temperatures and host plants. Developmental periods from egg to pre-adult of whiteflies measured under four constant temperatures: they were 86.2 days at $15^{\circ}C$ and 17.0 days at $30^{\circ}C$. Lower threshold temperature and total effective temperature for the development of egg and nymph, and for the complete development (egg to emergence) were $10.1,\;11.6,\;11.1^{\circ}C$ and 110.3, 204.7, 317.3 degree days, respectively. The hatching and emergence rates were 87.0% at $25^{\circ}C$ and 76.7% at $20^{\circ}C$, which were higher than the results of other temperatures. The adult longevity was 23.6 and 14.0 days at $20^{\circ}C$ and $30^{\circ}C$, respectively. The highest average fecundity per female was 103.3 at $25^{\circ}C$. But there were no significant differences among the temperatures. The highest intrinsic rate of natural increase($r_{m}$) was 0.196 at $30^{\circ}C$ and the highest net reproduction rate ($R_{o}$) was 97.33 at $25^{\circ}C$. Developmental periods from egg to pre-adult of whiteflies were 21.2 on the tomato, 28.1 on red pepper, 22.2 on eggplant and 25.5 days on poinsetia. The hatching was highest (90.3%) on red paper and emergence rate was highest (89.6%) on eggplant. The longest longevity of adult female was 26.5 days on eggplant, and the average fecundity per female was greater on tomato and eggplant than on other host plants. The intrinsic rate of natural increase($r_{m}$) was the highest on tomato as 0.165 and the net reproduction rate ($R_{o}$) was the highest on eggplant as 106.1. As a result, the optimum range of temperature for the growth of B. tabaci was between $25^{\circ}C$ and $30^{\circ}C$, and the optimum host plant were tomato and eggplant among the plants tested.

• Food Science and Preservation
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• v.13 no.2
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• pp.131-137
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• 2006

In order to reduce the damage of effective component during processing, we carried out hot-water extraction monitering in Gastrodia elata Blume by response surface methodology. The extraction con야tions for vanillyl alcohol, vanillin and coumarin were optimized at 91.07, 93.73 and $96.30^{\circ}C$, for 2.64, 2.58 and 3.84 hr, at the concentration of 15.16, 21.56 and 19.88 mL/g, respectively. The optimal condition for extraction of total phenolics was acheved at $98.14^{\circ}C$, 3.20 hr and 18.63 mL/g. This study elicited regression formula for each variable, and superimposed the total optimal conditions of extraction for effective compounds and optimal condition for antioxidant characteristics dividing processing factors. It is shown that the predicted result under the extraction condition as follows: extraction temperature for $90{\sim}100^{\circ}C$, extraction time for $3{\sim}4hr$, and solvent volume of $15{\sim}20mL/g$ of sample.

• Korean journal of applied entomology
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• v.40 no.4
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• pp.297-300
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• 2001

Development and reproduction of the persimmon fruit moth, Stathmopoda masinissa, were investigated under different temperatures (15, 20, 25, and 3$0^{\circ}C$). It took 96.1 days to grow from egg to adult at 2$0^{\circ}C$, 43.2 days at $25^{\circ}C$, and 34.6 days at 3$0^{\circ}C$. At 15$^{\circ}C$, all tested individuals died before pupation. The developmental threshold temperatures for egg, larva, pupa, and adult were 12.2, 13.5, 13.8, and 13.4$^{\circ}C$, respectively. The total effective temperatures for egg, larva, pupa, and egg to adult were 74.0, 331.3, 160.5, and 569.9 degree days, respectively. The hatching, pupation, and emergence rates were highest at $25^{\circ}C$. The average life span of adult prior to laying eggs and the total life span of adult were 12.6 and 29.3 days at 2$0^{\circ}C$, 3.8 and 8.6 days at $25^{\circ}C$, and 2.5 and 7.0 days at 3$0^{\circ}C$, respectively. Mean generation time in days (T) was shorter at higher temperature. Net reproductive rate per generation (R$_{o}$) was lowest at 2$0^{\circ}C$. The intrinsic rate of natural increase (r$_{m}$) was highest at $25^{\circ}C$ as 0.066.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.461-467
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• 2012

Developmental characteristics of Geocoris pallidipennis were investigated at a constant temperature ($20{\pm}1$, $25{\pm}1$, $30{\pm}1$, $35{\pm}1$, $37.5{\pm}1$ and $40{\pm}1^{\circ}C$), under long day illumination 16:8 (L:D) and constant relative humidity ($80{\pm}10%$). From egg to adulthood, the lower developmental threshold and the effective accumulative temperature were $14.8^{\circ}C$ and 399.1 day-degree, respectively. The experimental results at $35^{\circ}C$ were as follows. The egg period was 5.6 days (hatchability: 81.1%) and the nymphal period was 14.3 days (1st: 3.2, 2nd: 2.2, 3rd: 2.7, 4th: 2.7, 5th: 3.6). Female longevity was 33.8 days and the oviposition period was 29.2 days. Total egg production was 111.2 eggs and the maximum daily egg production was 14.8 eggs (in 7th days). However, although some eggs and nymphs developed at $37.5^{\circ}C$, G. pallidipennis could not develop at $40^{\circ}C$, The total egg production at $40^{\circ}C$ was only 22.1 eggs. When G. pallidipennis was fed on Bemisia tabaci pupae, daily prey consumption by nymphs (1st, 3rd and 5th) and adults was 1.9, 7.3, 18.7 and 29.5, respectively.