• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.935-942
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• 2017

In the present study, kohlrabi-kimchi was prepared for assessment of changes in sensory qualities and measurement of changes in quality characteristics according to the storage period for the purpose of using kohlrabi as an ingredient of Kimchi. Examination of the physicochemical properties of kohlrabi-kimchi according to the storage period showed that the acidity increased steadily throughout the storage period, while soluble-solids content, pH and hardness decreased as the storage period elapsed. Meanwhile, the L value increased and then it decreased as the storage period elapsed, but, the a value increased and the b value gradually decreased after day 14 of storage. Reducing sugars increased up to day 10 of storage, and then they decreased slowly after day 15 of storage. Measurement of changes in lactic acid bacteria in kohlrabi-kimchi according to the storage period showed bacterial growth showing typical tendencies of Kimchi with a rapid increase on day 5 of storage and a decrease thereafter. Assessment of sensory qualities of kohlrabi-kimchi according to the storage period showed that the highest scores for appearance and sourness, odor, texture, and overall scores were obtained on day 15 of storage. Based on the above results, it was determined that the optimal maturity period of kohlrabi-kimchi is day 15 of storage.

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.348-357
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• 1998

To meet the demand for high quality of foods with the expanded implementation of foodservice into kindergarten, and to make the efficient use of resources, the necessity of introducing central production unit with cook/chill system into kindergarten foodservice is getting increased. The purpose of this study were to develop standardized recipe applicable to cook/chill system for kindergarten foodservice and to evaluate the microbial and sensory quality. For quantitty production of cook/chill system in kindergarten foodservice, Korean traditional starch foods were selected as menu items. The followings are summary of the results： 1. Standard recipes to produce Various Boiled Rice (Boriebap and Yackbap) and Rice Cake (Chapsal-pat-sirutuk) for cook/chill system have been developed. 2. The microbial quality of Boribap, Yackbap and Chapsal-pat-sirutuk during 10 days chilled storage was very excellent. And in this experiment, the stability of storage of standard recipes of Boribap, Yackbap and Chapsal-pat-sirutuk at cook/chill system was proved for 10 days. 3. In the result of sensory evaluation, apperance of Boribap was decreased significantly on the third day of storage (p<0.005). The rest of the item of sensory evaluation of Boribap has no significance between the first day and the third day of storage. The tenderness (p＜0.05) and gelatinousness (p<0.005) of Yackbap had been rated high significantly in the third day of storage than the first day of storage. The rest of the item of sensory evaluation of Boribap has no significance between the first day and the third day of storage. The color and chewiness of Chapsal-pat-sirutuk was decreased significantly on the third day of storage (p＜0.05). The rest of the item of sensory evaluation of Chapsal-pat-sirutuk has no significance between the first day and the third day of storage.

• Food Science and Preservation
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• v.4 no.3
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• pp.251-258
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• 1997

The quality changes of strawberries packaged using low density polyethylene (LDPE) film filled with 3% silver-coated ceramic (WC30) and filled with it and 0.1% chitin (CWC) were investigated during storage at 2$0^{\circ}C$ for 5 days. In gas composition within film bag, CWC and WC30 kept higher CO2 concentration than LDPE without silver-coated ceramic and chitin (CO) did during 5 day storage. The weight loss of strawberries during storage was the smallest in WC30 and the largest in CWC in 5 days. Hardness of strawberries was the highest in WC30 and the lowest in CO during 5 day storage. pH of strwberries was increased a little until 1 day and was not changed after 1 day storage, and soluble solid content was not changed during storage. Vitamin C content was decreased significantly until 2 day storage and decreased a little after 2 days. There is no differences in the change of vitamin C content among the packaging materials. In color measurement, lightness was the highest in WC 30 and in sensory evaluation, all characteristics also had the highest scores in WC30. In conclusion, better quality of straberries was shown in WC30 than in CWC and CO during storage.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.95-103
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• 2008

The aim of this study was to evaluate the physicochemical, microbial, and sensory characteristics, as well as antioxidative activities of yoghurts containing spirulina powder, during storage at 4$^{\circ}C$. The pH of the yoghurts decreased until the 9th day of storage, but significantly increased by the 12th day. Total acidity also increased until the 9th day of storage, and then significantly decreased by the 12th day. Sugar content did not change significantly (approximately 18 $^{\circ}Brix$). Viscosity(cP) increased until the 6th day of storage, but had decreased at the 12th day. The viable bacterial cell counts of the control group decreased during storage. In contrast, the viable cell counts of the spirulina containing samples increased until the 9th day, and then decreased by the 12th day of storage. Antioxidant activity decreased in all groups, but the changes in antioxidant activity were lower in the spirulina groups than in the control group. According to sensory evaluations, the samples presented no significant differences during storage. Based on the above results, the optimum concentration of spirulina was determined as 0.25%. Also, the period of circulation of yoghurt containing spirulina was estimated to be 9 days at 4$^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.1033-1038
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• 2012

This study was done to provide basic information about the storage and distribution of specialty grade coffee of which the market will be expanded through customer sensory evaluation according to the storage period of specialty grade coffee by the SCAA classified method with consideration to defective beans and scent. The specialty grade coffee sample of this study was extracted on day 1, day 14, and day 28. The water content showed a significant reduction on the 28th storage day and there was no pH change according to the storage period. Color degree was brightened according to the preservation period before and after grinding but there was no significant difference. The panels for sensory evaluation considered of 24 university. The sensory evaluation consist of aroma, bitterness, and astringency, acidity, aftertaste, overall satisfaction, and items for strength estimation consist of aroma, acidity and bitterness. The sensory evaluation was expressed by applying a 5 point Likert scale. The results showed that as the storage period increased so too did the aroma and the strength of bitterness. Preference was the highest on day 1 in every items except aroma and astrigency. However on day 14 and day 28, most of the sensory evaluation became low and then became high, which was inconsistent. Male students were not consistent in their evaluation according to the preservation period, but female students rated aroma and bitterness the lowest on preservation period day 1 and they prefer after a storage period of 1 day in regards to the entire degree of satisfaction including sour test. astrigency and aftertaste. The analysis of visiting frequency for coffee shops used demonstrated that the longer the preservation period, the lower the preference but was not significant in the case of involving a little frequency group. The group that did not like Americano coffee evaluated that the longer the preservation period, the lower the preference based on Americano coffee preference analysis. There was no consistency between the storage period day 14 and day 28 in strength and preference, but preference for storage period day 1 was high in every group, which means that the quality of coffee is affected by the preservation period.

• Journal of the Korean Home Economics Association
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• v.42 no.1
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• pp.167-180
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• 2004

This study was carried out to investigate quality characteristics of chopped garlic stored at various temperature. Chopped garlic was stored at room temp.($25^{\circ}C$), refrigerator temp.($5^{\circ}C$) and frozen temp. ($-18^{\circ}C$) for 1, 2, 4, 8, 24, 48, 72 hours(room temp.) and 1, 3, 5, 7, 10, 15, 20, 30 days(refrigerator temp. and frozen temp.), respectively. Brown color, Hunter color value, vitamine C contents and flavor patterns by electronic noes of chopped garlic were measured. Fresh chopped garlic was used as control and garlic powder by hot air drying was used for comparisons. Brown color of chopped garlic increased with increasing storage time, and the intensity of that was reduced as following order such as chopped garlic stored at room temp., refrigerator temp. and frozen temp. Brown color of garlic powder was most dark amomg all the samples. The results of Hunter color value was consistent with then of brown color in chopped garlic, whereas those of garlic powder showed relatively low browning. Above results might be caused by the difference of measurement as only surface color was measured in Hunter color value unlike brown color. Vitamine C contents of chopped garlic decreased with increasing storage time, and in particular those stored at room temp. decreased markedly as retention of those stored at room temp. was 60％ of control after 1 day storage. Vitamine C retention of chopped garlic stored at refrigerator temp. was 78％ of control after 10 day storage and that stored at frozen temp. was 86％ of control after 30 day storage. At room temp., flavor pattern by electronic nose showed a difference between chopped garlic stored for 1hour and control, and showed occurrence of off odor after 1 day storage. Flavor pattern of garlic powder by electronic nose showed a mild flavor. Flavor patterns of chopped garlic stored at refrigerator temp. were similiar until 10 day storage, whereas those showed occurrence of volitile components after 15 day storage. Flavor patterns of chopped garlic stored at frozen temp. were similiar after 30 day storage, and especially those after 3 day storage were almost the same as control. Therefore it is desirable to store chopped garlic within 1 day at room temp. and within 10 days at refrigerator temp. And it is most desirable to store chopped garlic at frozen temp. as retention of quality characteristics was superior than other storage temp.

• Korean journal of food and cookery science
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• v.17 no.2
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• pp.149-155
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• 2001

Namul cooked with the standard recipe was examined by research of microbiological test for three months and sensory evaluation of frozen namul after reheating. When the namul was freezed storage, in the microbiological test namul began to change on the 40th day, but there was no problem about stability of storage until 3 months. The overall qualities of taste, flavor, color and texture were examined by sensory evaluation of frozen namul after reheating. The pH was seemed to change slowly, its color was changed on the 20th day from the beginning of storage. Radish root represented substantial difference in texture and overall quality on the 20th day. The off-flavor of immature pumpkin stated on the 25th day. Later 10days nettle tree mushroom began to be changed in its taste, texture, overall quality and appearance, then on the 25th day it was seemed to have low preference. But oak mushroom kept its quality good for 25 days. Oyster mushroom was changed in color, appearance and overall quality on the 20th day. Bracken had low preference in taste, texture and moisture on the 25th day. The color of spinach was changed on the 15th day, and its taste on the 20th day. Soybean sprout was changed in taste, texture and overall quality on the 15th day, and overall quality marked low preference on the 25th day Root of bell flower was changed on the 25th day(p<0.05).

• Korean journal of food and cookery science
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• v.30 no.5
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• pp.588-595
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• 2014

To develop a variety of salted vegetables, this study investigated the quality properties and sensory characteristics of pak-choi Baikkimchi with 0, 1, 3, 5 and 7% (w/w) red pepper seed during 50 days at $10^{\circ}C$. The pH of pak-choi Baikkimchi decreased little for the first days but decreased significantly after day 20. The larger amount of the red pepper seed kept pH the less affected. The total acidity of pak-choi Baikkimchi increased within 20 days. Lactic acid bacteria count, pak-choi Baikkimchi with 0% red pepper seed decreased after 30 days' increase, while pak-choi Baikkimchi with 3% and 5% red pepper decreased significantly after 20 days' increase. Hunter's color L value increased during storage but a and b value decreased. Pak-choi Baikkimchi with 0%, 5% and 7% red pepper seed on day 10, pak-choi Baikkimchi with 1% 3% red pepper seed on day 20. Flavor preference was higher on day 20 of storage. In taste analysis, pak-choi Baikkimchi with 3% and 7% red pepper seed higher preference on day 10 and with 5% on day 30. Appearance preference was higher for pak-choi Baikkimchi with 0% and 3% red pepper seed on day 10 and with the others on day 20. Texture preference decreased as the storage time. Overall preference of pak-choi Baikkimchi with 0%, 1% and 7% were higher on day 10, pak-choi Baikkimchi with 3% and 5% red pepper seed were higher on day 20. In conclusion, the quality properties and sensory characteristics of pak-choi Baikkimchi were optimal on day 20 of storage and 3% red pepper seed.

• Culinary science and hospitality research
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• v.24 no.2
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• pp.63-70
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• 2018

In this study, the fatty acid content and quality characteristics of the massless enegy treated commercial milk products stored at $30^{\circ}C$ were investigated. The pH of pasteurized milk decreased significantly. UHT milk showed also significant decrease in pH to 4.70~5.72 on the 8th day of storage which was higher than control even there was no significant differences. The acidity of pasteurized milk decreased significantly from the 2nd day of storage to 0.13~0.65% in treatments and control and control was 0.94% at the 8th day of storage and 0.35% in the treatment of ultra high temperature milk. The solid content of pasteurized milk was $7.5^{\circ}Bx$ at 1 day after storage, which showed significant differences from the $11.2^{\circ}Bx$ in the treatment. Pasteurized milk showed more bacterial growth in the treatment than in the control. After 4 days of storage, there was no bacterial count in pasteurized milk but it increased significantly $1.9{\times}10^8$ and $4.5{\times}10^6$ each in UHT milk. Lactic acid bacteria were detected in the curd $2.0{\times}10^6$ in the control and $2.0{\times}10^8$ in the treatment at the 4th day. Palmitic acid content in the saturated fatty acid was the highest at 35.4~41.4% in both pasteurized and ultra high temperature milk. In the UHT milk, linolenic acid was significantly increased to 3.8% in the treatment compared with 2.9% in the control at the 4th day of storage. Therefore, commercial ultra high temperature milk with physical treatment to increase beneficial bacteria showed significant difference compared to the control after 5 days of storage in this experiment.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.11
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• pp.982-993
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• 2000

This paper describes an optimal control scheduling of an encapsulated ice storage system with a chiller of nominal chiller 34RT(103,200kcal/hr) and an ice storage tank of 170RT-hrs(514,080 kcal). The optimization technique used in the study is dynamic programing. The objective function is summed cost during a day including charge and discharge periods. Control strategies being used commercially are chiller priority and storage priority control. In chiller priority control, the chiller is allowed to run at full capacity during the day, subject to limitations of the building load, and the ice is only melted when and if the load exceeds the chillers full capacity. In contrast to chiller priority control, the aim in storage priority control is to melt as much as ice as possible during the day time period. The system simulation calculates the operation costs for the three control strategies in the condition of the same cooling load and the same ice storage system. The simulation period is a day, assuming that initially the tank is stored fully and the cooling load is perfectly predicted for the scheduling. Also Final state of the tank is to be charged fully.