• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.135-136
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• 2003

알코올 분무, 셀로판지 부착 등의 표면처리가 포장김치의 표면갈변과, pH, 산도, 균수 및 관능적 품질에 미치는 영향을 조사하였다. 실험에 사용된 포장김치는 200 g 들이 플라스틱 용기에 김치를 담은 후 무처리, 70% 알코올로 표면을 1회 분무한 것, 김치표면에 폴리에틸렌필름(두께 0.04 mm)을 부착하여 저장실 (10$\pm$1$^{\circ}C$)에서 21일간 저장하면서 3일 간격으로 조사하였다. 그 결과, 무처리와 알코올을 분무한 경우는 저장 15일째에 pH가 4.0수준에 도달하였으나 김치표면에 polyethylene film을 부착한 경우는 21일째까지도 pH가 4.0 이상을 유지하였다. 산도의 경우도 pH와 동일한 경향을 나타내어 polyethylene film으로 표면처리함으로서 김치의 숙성이 지연되었다. 무처리와 알코올을 처리한 것은 12일째부터 김치표면이 갈변하기 시작하였으며 18일째는 그 갈변정도가 심하였다. 그러나 polyethylene film을 표면에 부착한 경우는 저장 21일째까지도 갈변정토가 미약하였다. 저장기간에 따른 총균수의 변화는 무처리와 알코올을 처리한 경우가 polyethylene film을 부착한 경우에 비하여 증가폭이 컸으나 젖산균수는 반대로 polyethylene film을 부착한 경우가 무처리 또는 알코올을 분무한 경우에 비하여 높아 김치의 품질이 양호하였다. 무처리와 알코올을 분무한 김치의 표면에는 저장 15일 이후에 산막표모 및 곰팡이의 균사체가 번식하는 김치도 발견되었다. 처리별 이미 및 이취의 발생정도를 조사한 결과 무처리와 알코올을 처리한 경우는 저장 15일경에 특히 용기 표면에 위치하는 김치에서 이미와 이취가 있었으나 polyethylene film을 부착한 경우는 이미와 이취가 전혀 나타나지 않았다.채반에 넣고 밀도를 측정한 결과 1.002g/㎤을 나타냈다. 즉 물의 이론밀도인 1g/㎤에 근접한 값을 보여 정확한 밀도 계측이 가능한 것으로 판단되었다. 또한 밀도 계측시스템의 측정 반복간 정밀도를 파악하기 위해 수박 6개를 임으로 선정하여 3반복 측정 시험한 결과, 측정표준편차가 0.001~0.004g/㎤로 해상도보다는 다소 높았으나 대체로 양호한 결과를 나타냈다. 수박 35개를 이용하여 개발 계측시스템과 사람이 직접 부력법으로 밀도를 측정 비교한 결과, 계측시스템에 의해 측정된 수박 밀도가 사람이 측정했을 때 보다 낮게 측정되었다. 수박의 외관인자(무게, 길이, 직경, 체적), 밀도와 당도의 상관관계 구명시험을 위해 원예연구소 시험포장에서 재배된 삼복꿀수박 총 74개를 공시재료로 하였고, 시험은 출수일별로 10~14개씩 수확하여 외관인자, 밀도, 당도를 각각 측정하고, 이들 인자들간의 상관관계를 구명하였다. 외관인자들간에는 높은 상관관계를 보였으나, 외관인자들과 밀도, 외관인자들과 당도, 밀도와 당도와는 매우 낮은 상관관계를 나타냈다. 점성에 영향을 미치는 가장 주요한 조건이라고 생각된다.환원당인 sucrose 함량은 계속 증가하였고 fructose, glucose, sorbitol의 함량(추황의 sorbitol을 제외)은 생장이 촉진됨에 따라 증가하다가 다시 점차적으로 감소하였다. 이러한 결과는 총당과 환원당의 측정결과와 일치한 것으로 나타났다. 결론적으로 배의 성장에 따라 산 함량은 감소하였고 당 함량은 증가하였다.luco-pyranoside, quercetin 7-O- -glucopyranoside, acacetin 7-O-$\beta$-D-glucuronide and apigenin-6-C-$\beta$-D-glucopyranosyl-8-C-$\b

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.361-365
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• 2007

This study was conducted to improve the Prunus mume vinegar production. The most suitable concentration of the Prunus mume juice was 6%. Static fermentation was a more suitable process for acetic acid fermentation of the Prunus mume vinegar than shaking fermentation. Major components of the organic acids were acetic, citric, tartaric and malic acid at 4.2, 1.2, 0.3, and 0.1%, respectively. Also, major components of the free sugars were glucose and fructose, and 80.96 mg% of asparagine was included in the Prunus mume vinegar as a main free amino acid. Alcohol components of the Prunus mume vinegar were n-propyl alcohol, iso-butyl alcohol, n-butyl alcohol, iso-amyl alcohol, and n-amyl alcohol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1296-1302
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• 2013

The quality of fresh jujube (Zizyphus jujuba) fruit rapidly declines in the postharvest stage and thus the effective storage conditions for agricultural warehouses were investigated in this study. Fresh jujubes (~10 kg) were stored using five different storage methods: plastic box without further packaging as a control (C-PL), plastic box with hanji packaging (H-PL), plastic box with functional film packaging (F-PL), cardboard box with hanji packaging (H-CB), and cardboard box with functional film packaging (F-CB). The storage boxes were stored in a refrigerator ($0^{\circ}C$ and 80~90% RH), equipped with an ethylene gas scavenging device for 9 weeks and then the quality characteristics were analyzed. The control storage conditions of jujubes showed a substantial decline in quality with decreases in moisture content, hardness, and sugar content as well as increases in decay ratio and redness. Among the tested storage conditions, F-CB was most effective in terms of maintaining the quality of jujube fruit while maintaining firmness, weightlessness, ripening degree from redness and visible appearance. In conclusion, effective storage and packaging conditions during storage enabled maintenance of fruit quality of jujubes for 9 weeks.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.670-676
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• 2016

In this study, we analyzed the utensils, covers and mats that were used for making meju, the shape of meju, and the heating method used for making meju from the 225 ways of preparing jang mentioned in the 32 volumes of the ancient cook books from 530 AD to 1950. The heating method of traditional meju bean and starch included 57 kinds of steaming, 59 of boiling, 21 of roasting + boiling, and 2 of cooking. The shape of meju included 41 kinds of egg, 27 of ball, 22 of lump, a kind of doughnut, 8 kinds of hilt, 6 of flat, 4 of chip, and a kind of square. Among the 72 gochoojang meju, the heating method of bean included 9 kinds of boiling, and 6 kinds of steaming; whereas the heating method of starch included 19 kinds of steaming of dough, 11 of rice cooking, and 5 of boiling of dough. The utensils for molding of bean meju were 49 kinds of straw sack, 14 of round straw container, 11 of heating bed, 7 of large straw bowl or Japanese-snailseed, 5 of jar, 4 of ditch, 3 of straw bowls, 2 of pottery steamer of dough, 2 of gourd, and a kind of long round bamboo bowl and sack of straw. The cover and the mat used for molding of meju included 36 kinds of straw, 17 kinds of paper mulberry leaf, 15 of wide straw seat, 14 of mugwort, 11 of pine tree leaf, 10 of soybean leaf, 6 of cocklebur leaf, 6 of sumac leaf, 6 of barley straw, 6 of mulberry leaf, 5 of fallen leaf, 5 of cogon grass, 4 of reed seat, 3 of scrap of cloth, 2 of Indian bean tree leaf, a kind of reed. There were only 5 kinds of hanging.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.742-747
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• 1995

The effect of storage temperature and period on the contents of tin, iron, lead and vitamin C, browning index and pH was studied for canned and bottled orange juices currently sold in Korean market, which were stored for 24 weeks at 20, 30, 40 and $50^{\circ}C$ and analyzed at 4 week intervals. The change of metal content in bottled juices was negligible but metal release in canned juices was remarkably affected by storage temperature. Tin content after 16 weeks increased by $2.7{\sim}13.1$ times, iron content after 24 weeks increased by $4.3{\sim}5.2$ times and lead content after 24 weeks increased by $1.1{\sim}2.9$ times. Retention of total ascorbic acid in canned juices after 24 weeks at $30{\sim}50^{\circ}$ decreased to $13{\sim}76%$, while that in bottled juices decreased to $4{\sim}80%$. Browning index in canned juices after 24 weeks below $40^{\circ}C$ increased slightly with serious discoloration at $50^{\circ}C$ while that in bottled juices increased a little rapid. pH change in canned and bottled juices during storage below $40^{\circ}C$ was not observed regardless of container type but a great change of pH was accompanied with swelling of container ends in the case of canned juices after 24 weeks at $50^{\circ}C$.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.635-643
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• 2007

This study was carried out to investigate the quality of cooked rice prepared by-an electric pressure cooker (EPC) and an electric cooker (EC) during storage at different temperatures. Four rice cultivars were used (Ilpoom, Saechucheong, Sindongjin, and Sura). The cooked rice samples were stored at room and warm temperatures for 48 hr, and at refrigerator temperatures for 10 days. Immediately after cooking, the moisture content of the EPC rice was lower than that of the EC rice; yet pH was higher for the EPC rice. The L-value of the EPC rice was reduced due to an increasing b-value. The overall acceptability of the EPC rice was high; in particular, it scored high for a roasted nutty flavor and texture. During storage, moisture content and pH decreased regardless of the cooking method. L-, a- and b-values were similar at room and refrigerator temperatures over the entire period, whereas the a-value (greenness) of the EC rice stored at warm temperature slightly decreased and the b-value (yellowness) increased after 24 hr, resulting in a decreasing L- value. Also, sensory characteristics were not significantly different for the samples stored at room temperature for 48 hr; however, at warm and refrigerator temperatures, the sensory characteristics were significantly different after 24 hr and 3 days, respectively. In conclusion, the quality of the cooked rice was effectively preserved during storage at room temperature, and qualify deterioration oaf dependent on using warming equipment as well as the rice cultivar.

• Food Science and Preservation
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• v.24 no.7
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• pp.934-941
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• 2017

The objective of this study was to investigate the effect of corrugated packaging coated with aluminum (Al) on quality characteristics of red paprika during storage at $25^{\circ}C$. Characteristics such as weight loss, hardness, total phenolic content, antioxidant activities, polygalacturonic acid (PG) activity, and oxidative enzyme activities (polyphenol oxidase and peroxidase activities) of paprikas, packed in corrugated packaging with or without Al-coating were compared as a function of storage time. Al coating inside of corrugated box was found to inhibit PG activity, resulting in prevention of weight loss and maintenance of hardness of paprika during storage, compared to the control sample. This may be due to Al coating treatment that enhance moisture-proof property and hinder gas transmission of corrugated packaging. Furthermore, paprika in Al-coated-corrugated packaging was lower in oxidative enzyme activities than the control, which caused higher total phenolic content and antioxidant activities during storage. As a results, the Al coated-corrugated packaging can be used as a functional packaging material to extend the shelf-life and improve the storage quality of paprika by preventing their respiration and transpiration.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.243-246
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• 1993

For extending the shelf-life of Yukwa (oil puffed rice cake) which is one of the most favorable Korean traditional rice snack, the Yukwa was packed in $O_2$ preventive container and substituted the air with $N_2$ gas or packed with $O_2$ absorbent (ageless sachet). The quality of Yukwa stored at $35^{\circ}C$ was evaluated by POV, AV and TBA including sensory evaluation. The POV of oil in Yukwa of $N_2$ substitute pack and absorbent sachet included were 5.3 and 11.9 meq/kg, respectively, while no packing (control) was 195.5 meq/kg after 90 days storage at $35^{\circ}C$. AV and TBA were also same trend but the gap with the control was not so big. The Yukwa, $N_2$ gas substituted, was better in quality than absorbent treatment in sensory evaluation and no difference was detected in quality of 90 days storage Yukwa at $35^{\circ}C$ with 15 days. The main reason for lower sensory score of absorbent treatment was that the $O_2$ absorbent also absorbed the flavor component of Yukwa.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.216-220
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• 2002

The microbiological examinations of food service operations were conducted for the hygienic evaluation at four elementary schools in Busan, Korea. Total one hundred and seventy two swabbed samples using sponge were collected from the surface of environments, utensils and equipments of food service facilities and analyzed by measuring the total, coliform and psychrotrophic count. Sampling sites were the surfaces of floors, drains, walls, knives, cutting boards, rubber gloves, vinyl aprons, plastic containers, carriers, shelves, trays, dry shelves, electric tray dryer, food containers, soup containers, rice cookers, frying pans, boiling cookers, refrigerators, dumb waiters and dishwashers. The swabbed samples kept in an ice-parked box were transported to a laboratory and analyzed. The results demonstrated that the degree of contamination depended on the sampling sites. Averages of total counts of surface swab samples were ranged from 0.62 to 7.79 Log CFU/200 cm$^2$. The level of coliforms were ranged from not detectable to 5.26 Log CFU/200 cm$^2$, and those of psychrotrophs from not detectable to 6.15 Log CFU/200 cm$^2$. The severely contaminated sites were dumb waiters, drains, rice cookers, knives, plastic containers and floors. Also cutting boards, rubber gloves, carriers, drying shelves, vinyl aprons, boiling cookers, soup containers, frying pans and refrigerators were highly contaminated with the level of abode 3.5 Log CFU/200 cm$^2$. Therefore, those sites should be focused and controlled according to control points of sanitation standard operating procedures (SSOP). Also, periodic microbiological examination in addition to visual examination is recommended on these highly contaminated sites indicated above results at food service operations in elementary school.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.475-479
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• 2011

Although the storage period of raw baechu cabbage could be 2 months at $0{\sim}2^{\circ}C$, 1 month was appropriate considering the quality of the baechu cabbage, waste ratio, and storage cost. The polyethylene container was the most efficient storage container among polypropylene box, polypropylene net and polyethylene container. pH of a brined baechu cabbage using raw baechu cabbage was 4.0~4.3 after 8 weeks and its total bacteria and lactic acid bacteria counts were $10^7$ cfu/g, and textural property (springiness) lower than 50% was at 8th week of storage at $0{\sim}2^{\circ}C$ and thus its storage period was limited to 8 weeks. When brined baechu cabbage was prepared by raw baechu cabbage stored for 1 month at $0{\sim}2^{\circ}C$, its pH, microorganism counts and springiness showed similar trends to the brined cabbage using raw baechu stored for 0 month. However, its rates of change were faster than the brined baechu cabbage using the raw baechu, and the storage period was limited to 6 weeks. Brined baechu cabbage using the raw cabbage stored for 2 months and its storage period was limited by about 4 weeks judging by its indicated quality characteristics.