• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.417-420
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• 1996

We investigated the effect of green tea extract (GTE) on the sensory properties, color value and shelf-life characteristics (pH, titratable acidity and total bacteria count) of cooked rice. Sensory attributes such as taste, flavor and overall acceptability were significantly higher in cooked rices prepared with 500, 1000 ppm of GTE than those of control group (p<0.01) but there was no significant difference among samples (p<0.01) in textural quality. Redness, yellowness and total color difference (${\Delta}E$) were higher when GTE was added. When cooked rice was putrefied, the values of pH, titratable acidity and total bacteria count were about 5.8, 0.3% and $10^8$ cfu/g, respectively. The shelf life of cooked rice was prolonged to 1-2 day by adding 500 and 1000 ppm of GTE as compared to control group.

• Journal of Applied Biological Chemistry
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• v.56 no.1
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• pp.11-17
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• 2013

The effect of additives on the quality of ssamjang was investigated during storage. The L-, a- and b-values of ssamjang decreased gradually during storage, and the total color difference (${\Delta}E$) increased in the control group. The gas production of ssamjang was reduced in K-sorbate, alcohol and mustard added groups. The number of yeast increased rapidly up to 6 weeks of storage, then decreased in the mustard, alcohol, and K-sorbate added groups. The oxidation-reduction potential and water activity decreased until 6 weeks and 12 weeks, respectively, and then increased gradually. Titratable acidity increased with concomitant decrease in pH, however, it increased slightly in the K-sorbate and ethanol added groups. Reducing sugar content increased until 9 weeks of storage, except the turmeric added group. Alcohol content increased until 15 weeks in the Japanese apricot juice, and turmeric added group. The sensory test result for the taste, flavor and overall acceptability showed that mustard added ssamjang was more acceptable than other groups.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.206-206
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• 2003

피클(pickles)은 구미 각국에서 널리 애용되는 침채류이다. 수확한 농산물의 신선도를 유지하면서 장기보관 하기 위해 만들어진 것으로 여러 가지 방법이 시도되어 왔고, 동양에서는 높은 습도로 인한 곰팡이 증식을 억제하기 위하여 소금 절임 방법이 발달되었으며, 건조한 기후의 유럽에서는 세균번식을 억제하기 위하여 식초절임이 발달하였다. 피클이란 채소 또는 과실류를 소금, 식초 또는 여기에 향신료 등을 넣은 것에 절인 것을 총칭하는 것으로, 주로 오이, 컬리플라워, 양파, 미숙 토마토 등을 원료로 사용한다. 본 연구에서는 피클의 특징인 아삭아삭함을 유지하면서, 피클의 신맛과 한국 전통식장아찌를 혼용한 염장피클로, 기능적 특성을 가진 허브를 첨가하여 현대인에게 오는 성인병의 예방과 기능성 식품에 부가 가치를 높이고자 하며, 또한 피클 제조를 위한 고추의 품종 선정을 위한 기초 실험을 하고자 함에 있다. 풋고추, 청양고추, 꽈리고추 등 품종을 달리하여 제조한 고추피클의 숙성기간 중 품질특성을 실험하였다. 염도변화는 모든 품종에서 숙성기간이 길어질수록 염도가 낮아졌으며, 숙성이 완료되는 시점인 25일경에는 풋고추 2.95%, 청양고추 2.68%의 염도 변화를 보였다. pH변화는 세 품종간에 차이는 없는 것으로 보여졌으며, 숙성기간에 따른 차이도 거의 없는 것으로 나타났다. 고형분함량은 풋고추와 꽈리고추가 비슷한 경향을 보였고, 청양고추가 다소 높았다. 적정산도의 변화는 세 품종간에 차이는 없었지만, 숙성이 진행될수록 증가하는 경향을 보였다. 탁도변화는 꽈리고추가 가장 낮았고, 청양고추가 가장 높았으며, 숙성이 진행될수록 모두 탁해지는 경향을 보였다. 또한 피클의 경도변화는 풋고추는 0일에 45.12g 청양고추는 56.68g, 꽈리 고추 42.12g의 경도를 보였으며, 숙성최종단계인 25일에는 풋고추 20.33g, 청양고추 25.12g, 꽈리고추는 17.81g으로 꽈리고추의 경도가 가장 낮았고, 청양고추는 세 품종 중에서 가장 높은 것으로 나타났으며, 세 품종 모두 숙성이 진행될수록 경도가 현저히 낮아지는 것으로 나타났다.

• Food Science and Preservation
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• v.18 no.4
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• pp.436-441
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• 2011

The change in physicochemical and sensory properties and bioactive compounds of Campbell grape juice has been investigated for 30 days at $-5^{\circ}C$. The pH and sugar/acid ratio of the cold stabilized juice increased, while titratable acidity and soluble solids decreased as cold stabilization period is prolonged. Juice samples became lighter, yellowish to brownish and lesser red in color as can be observed with the increasing $L^*$ and $b^*$ values, and decreasing $a^*$ value, respectively. The juice cold stabilized for a shorter period of time showed higher levels of bioactive compounds and radical scavenging activity, and was more preferred by the panelists than the juice cold stabilized for a longer period of time. These results suggest that cold stabilization period affected the quality characteristics of grape juice.

• Food Science and Preservation
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• v.19 no.3
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• pp.323-327
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• 2012

The effects of ultrasound and ascorbic acid cotreatment on the browning inhibition and microbial growth of fresh-cut Tsugaru apples were investigated. The prepared samples were dipped in distilled water (Cont) or 1% (w/v) ascorbic acid solution (AA) and were then ultrasonicated in distilled water (US) or 1% (w/v) ascorbic acid solution (AA+US). The samples were then packed in a 0.04mm polypropylene bag ($20{\times}15$ cm) and were stored at $10^{\circ}C$ for eight days. The AA+US treated samples showed high $L^*$ and low $a^*$, $b^*$ values as well as inactivated PPO activity. The growth of the total aerobic bacteria also inhibited the AA+US treated samples more. The physicochemical properties were not different among all the samples. It was demonstrated in this paper that the ultrasonication treatment with ascorbic acid prevented the enzymatic browning of and microbial growth in fresh-cut Tsugaru apples.

• Food Science and Preservation
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• v.15 no.3
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• pp.347-351
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• 2008

The effect of microperforated packaging films on fresh-cut apples was studied Apples (Malus domestica Borkh. cv. Red Delicious) were cored and cut, packaged in laser microperforated film or non-microperforated polyolefin film, and stored for 3 weeks at 4C. The flesh firmness of apples packaged in microperforated film during the storage period was significantly higher than that of apples packaged in non-microperforated film, and the level of soluble solids was also higher. The browning index, titratable acidity, pH, acetaldehyde and ethanol levels were not affected by microperforation. These results show that microperforated films could be used for retention of flesh firmness in fresh-cut apples.

• Food Science and Preservation
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• v.15 no.3
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• pp.385-389
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• 2008

The effects of high vanillin concentration on fresh-cut apples treated with NatureSealTM were investigated Apples were sliced, treated with 6% NatureSealTM or 6% NatureSealTM + 120 mM vanillin, packaged in polyethylene bags, and stored for 3 weeks at 4C. The L value, soluble solid level and titratable acidity of fresh-cut apples treated with NatureSealTM + 120 mM vanillin during storage were lower than those of fresh-cut apples treated with NatureSealTMonly; the growth of total aerobic bacteria, yeast and molds were also more inhibited in fresh-cut apples treated with NatureSealTM + 120 mM vanillin. These results show that the addition of 120 mM vanillin inhibits the growth of microorganism but 1m detrimental effects on the quality characteristics of fresh-cut apples treated with NatureSealTM.

• Journal of the Korean Chemical Society
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• v.37 no.6
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• pp.562-569
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• 1993

The pseudophase separation model is used to describe the effects of pH and n-propanol on the mixed micellar formation of protonated and unprotonated dimethyldodecylamine oxides. Dimethyl-dodecylamine oxide surfactant molecules may exist in aqueous solution in either nonionic (unprotonated) or cationic (protonated) form, and they can be modeled thermodynamically as a binary mixture of cationic and nonionic surfactants. The composition of the binary mixture is varied by adjusting the solution pH. And activities, micellar compositions, and monomeric compositions of two surfactant species can be calculated directly from the experimental titration data by applying pseudophase separation model to the micellar system of DDAO in water/n-propanol. The critical micellar concentrations and the p$K_a$ values of the binary mixture systems are dependent on the micellar composition of the protonated cationic surfactant (X); especially they show the minimum phenomena when they are plotted against the micellar composition of the protonated cationic surfactant (X). The critical micellar concentration of the binary mixed DDAO system is generally decreased when n-propanol is added to the binary mixture system, and the degree of decrease is dependent on the concentration of n-propanol.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.365-367
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• 2004

Electrolyzed-acid water was used to prolong shelf life of salted Chinese cabbage during storage, Chinese cabbage was salted, washed twice with electrolyzed-acid water, packaged in high-density polyethylene film, and stored at $10^{\circ}C$. Titratable acidity, pH, color, and microbial loads of salted Chinese cabbage were measured. Treated sample showed lower pH, total microbial count, and lactic acid bacteria than those of control, whereas almost equal titratable acidity and color, Acidity of treated sample maintained lower pH value until 6 days, and remained constant thereafter, Sharp decrease in L value occured after 2 days for control, and was delayed 4-6 days for treated sample. Salted Chinese cabbage treated with electrolyzed-acid water showed lower total microbial load ($10^3\;CFU/mL$) and lactic acid bacteria ($10^1\;CFU/mL$) after washing, whereas similar loads, compared to control after 6 days. Treatment with electrolyzed-acid water maintained higher quality for salted Chinese cabbage, with limited shelf life extension.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.334-344
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• 2014

The objective of this study was to evaluate the microbiological and physicochemical characteristics, and the antagonistic activity against Helicobacter pylori ATCC 43504, of yogurt fermented with the lactic acid bacteria from Baikkimchi kept under cold storage. The viable cell counts, titratable acidity, viscosity, and total solid content of the yogurt were different according to the bacterial strains used for fermentation. There was no significant change (P>0.05) in the various properties of refrigerated yogurt. Among the tested strains, the strongest resistance against artificial gastric juice and bile salt was found for Lactobacillus brevis BK11 and Lactobacillus paracasei BK57. Due to high lactic acid levels obtained from these two lactic acid bacteria, yogurt may show good anti-Helicobacter effects according to the time-kill assay. In particular, yogurt fermented with L. brevis BK11 significantly reduced the number of H. pylori adhering to gastric epithelial AGS cells and the urease activity of this pathogen (P<0.05).