• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.228-230
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• 2007

In this study, we investigated the change in lead content of canned coffee drinks while kept for 16 weeks in an incubator adjusted to $65^{\circ}C$. Our research aim was to ensure the safety of canned coffee purchased from vending machine and stores. The lead analysis were conducted by graphite furnace atomic absorption spectrometry after wet digestion using concentrated nitric acid. The results showed that the lead contents of all examined samples were very low at a level of not detected to 0.033 mg/L, and below 2 mg/kg, the Korean regulatory limit for the commodity. Also, no increase in lead content was observed over the elapsed time. Therefore, it appears that lead is not a hazard and need not be a concern in drinking canned coffee.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.2
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• pp.21-25
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• 1982

The changes in color and anthocyanins from raspberries which was added various saccharides and stored at room temperature, $5^{\circ}C$ and $-20^{\circ}C$, were investigated. (1) There are little changes in sugar density, pH, and acidify for 80 days. (2) Optical density of the juice (at 520nm) and the total anthocyanin content decreased during the storage period, the total anthocyanin content remains more than juice of raspberries. (3) Many saccharides effectively maintained the enrichment of absorbance at 520nm duriag storage. Hexose, especially D-galactose, had the most hyperchromic effect followed by disaccharides and then pentose. (4) The stability of anthocyanin pigment in the presence of sugar was markedly influenced by storage temperature. Especially cold temperature $(5^{\circ}C)$ was good for holding the pigment.

• Food Science and Preservation
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• v.5 no.1
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• pp.23-28
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• 1998

The objective of this study was to investigate the methods of quality maintenance using modified atmosphere packaging with various quality preservatives at ambient and low temperatures. Ethylene(<1.0ppm) accumulated during modified atmosphere storage of Chinese cabbage using polyethylene film(60$\mu\textrm{m}$) caused quality deterioration such as yellowing and abscission. The addition of potassium permanganate reduced ethylene level and thus extended storage life of l00% at 20$^{\circ}C$ and 140% at 0$^{\circ}C$. To establish the storage conditions of minimally processed sit and vegetables, the experiment was conducted with various quality preservatives and packaging materials. Ceramic film(Zeolite 7%, 60$\mu\textrm{m}$) showed increasing storage life of 50%, reducing total microbial counts of 50% and keeping high appearance quality of minimally processed pears stored at 20$^{\circ}C$ and 0$^{\circ}C$. Minimally processed Chinese cabbage treated with l% CaCl2 at 20$^{\circ}C$, and 1% CaCl2 and 1% NaCl at 0$^{\circ}C$ has a longer storage life of 90% with good maketable quality. Treatment of 1% NaCl for cut Asian penis appeared increased storage life of 100%, decreased cut surface browning and the best overall acceptability by a sensory panel.

• Food Science and Preservation
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• v.5 no.1
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• pp.49-56
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• 1998

The effects of the water extracts from thyme(TM) and tarragon(TG) on shelf-life and quality of kimchi were investigated by measuring the changes in pH, acidity, number of total microorganisms, number of Lactobacillii and Leuconostoc during fermentation at 1$0^{\circ}C$, and were tested for antimicrobial activities against Lactobacillus plantarum and Leuconostoc mesenteroides. TM and TG were extracted with water, ethyl ether, ethyl acetate and ethanol. Water, ethyl ether, ethyl acetate and ethanol extracts of TM showed antimicrobial activities against Lactobacillus plantarum and did not observed against Leuconostoc mesenteroides. On the other hand, water, ethyl acetate and ethanol extracts of TG showed antimicrobial activities against Leuconostoc mesenteroides and did not observed against Lactobacillus plantarum. The decrease of pH and the increase of acidity showed lower in kimchi prepared by adding water extracts from TM than in products from TG. The number of total microorganisms were also detected less in the kimchi prepared by adding water extracts from TM. And, the properties of barkless of kimchi measured instrumentally were higher for kimchi prepared by adding water extracts from TM, also maintaining good crispness. The optimal addition amounts of both TM and TG for good overall and spicy taste of kimchi were 0.03%. The results suggested the possible use of the extracts of TM and TG can be successfully used for the quality and extension of shelf-life of kimchi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.932-936
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• 1996

Scallop, Pectinopecten yessoenis(Jay), cultivated in the cold east coast of Kwangwon region, Korea, is expected be to produced about 50, 000 tons in the year 2000. Scallop, first of all should be exuviated to process for new goods. In this study, vacuum and nitrogen packagings were applied to extend the shelf-life of exuviated scallop boiled with steam for 10 min. Vacuum and nitrogen packagings retarded the decrease in pH, whereas inhibited the production of $NH_2-N, $ VBN, TMA, and TBA of exuviated scallop stored at $5^{\circ}C.$ They also inhibited the microbial growth. But, there was no significant difference in the bacteriostatic effects between both packaging methods. The estimated shelf-lives of boiled and exuviated scallops for control, vacuum, and nitrogen packagings were about 30, 36, and 36 days, respectively.

• Korean journal of food and cookery science
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• v.8 no.1
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• pp.27-30
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• 1992

The changes on the pH and acidity of kimchi with the addition of different amounts of onion were inverstigated during fermentation at $14^{\circ}C$ and $21^{\circ}C$ for 20 days. As the fermentation period increases, the pH of kimchi contained onion was higher than that of control kimchi, and tokal, volatile and non-volatile acidity of kimchi contatined onion were lower than those of control kimchi, at $14^{\circ}C$ and $21^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.456-461
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• 1997

Sodium lactateand sodium citrate, traditional food preservatives, were added to extend the shelf-life of the loow-salted Myungran-jeot, and various chemical and microbiological analyses were carried out with Muungran-jeot, and various chemical and microbiological analyses were carried out with Myungran-jeot femented at 1$0^{\circ}C$. pH was decreased in the beginning stage of fermentation and then increased, whereas the content of lactic acid was increased during fermentation. But, lactic acid production of the low-salted Myungran-jeot with preservative were lower than control. The NH$_2$-N content of the low-salted Myungran-jot with sodium citrate was increased in the beginning of fermentation and then decreased. Sodium citrate inhibited the productions of VBN and TMA during the fermentation of Myungran-jeot, whereas sodium lactate inhibited the productions of VBN and TBA. Sodium lactate inhibited the growths of proteolytic bacteris and fungi. The estimated shelf-lives of the Myungran-jeot with control, sodium lactate, and sodium citrate were about 11, 13, and 13 days, respectively.

• Food Science and Preservation
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• v.1 no.2
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• pp.81-86
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• 1994

This study examined the quality change of red peppers during storage at various temperatures and humidities. It was observed that red peppers showed mold at aw 0.75(>25% water content), discoloration at aw 0.33(<10%) and browning at aw 0.75(>19%). The most ideal condition of the storage for red peppers was a 13∼15% water content and 60${\pm}$5% RH. The storage life for whole red peppers were 2.0 months at 40$^{\circ}C$, 13.6 months at 25$^{\circ}C$, 27.3 months at 15$^{\circ}C$, 30.0 months at 10$^{\circ}C$, and 65.0 months at -3$^{\circ}C$. During any storage period above, level of capsanthin, browning and capsaicin were changed for whole peppers. Browning appeared to be a crucial factor for marketable quality of stored red peppers. It was found that the level of capsaicin & capsanthin have a miner relationship with marketable quality for consumer. Storing red peppers in nitrogen and vacuum atmosphere packing condition was found to be better than storing them in air at various temperatures in terms of storage life and quality maintenance. The nitrogen gas packaged red peppers kept longer shelf life and better quality compared with vacuum packaging.

• Food Science and Preservation
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• v.6 no.3
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• pp.333-338
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• 1999

This studies were conducted to investigate the effects of calcium lactate and calcium acetate on the duality and shelf-life of kimchi. Kimchi was prepared by adding 0.5% mixtures of calcium lactate and calcium acetate at ratios of 04:0, 0.4:0.1, 0.3:0.2. 0.2:0.3, 0.1:0.4, 0:0.5, and fermented at 10$^{\circ}C$. The shelf-life of the kimchi by adding the mixtures of calcium lactate and calcium acetate at the ratio of 0.4:0.1, 0.3:0.2, 0.2:0.1 can be extended approximately 5 days. And, calcium contents of the kimchi tissue increased 46 to 66% against the control products. And also, demage of parenchyma cell was lower, the scores of crispness and overall taste of the kimchi treated were higher than those of the control.

• Food Industry And Nutrition
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• v.7 no.3
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• pp.39-43
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• 2002

본 연구에서는 전통적으로 한방에서 성장 촉진을 위하여 사용된 녹각, 우슬, 구기자, 두충, 오미자 및 용안 등의 한약재 추출물과 액상칼슘을 각각 첨가하여 4구간의 빵을 제조하여 품질 특성을 비교 분석하였다. 빵의 물성을 측정한 결과, strength, hardness는 한약재 추출물과 액상칼슘의 첨가량이 많을수록 높아지는 경향을 나타냈었으며 cohesiveness, springiness, gumminess 및 brittleness는 감소하는 경향으로 나타났다. 빵의 내부와 표면의 색도(L,a,b)는 첨가량에 따라 차이가 있었으며 저장 4일째에 각각 변화 정도의 차이가 있었다. $37^{\circ}$ 에서 4일간 저장 후 일반세균은 무첨가구 $15\times10^3CFU/g$에 비하여 한약재 추출물 및 액상칼슘 첨가량이 많은 구간에서는 급격히 감소하여 보존성이 높게 나타났다. 관능적 특성은 실험구간에 따른 유의적 차이는 크게 나타나지 않았으며, 각각의 실험구간에 따른 칼슘함량을 비교 분석한 결과. 한약재 추출물과 액상칼슘이 많은 구간에서 높게 나타나는 경향이었다. 이상의 결과를 바탕으로 성장촉진 한약재 및 액상칼슘을 기능성 소재로서 제빵에 활용 가능할 것으로 생각된다.