• Journal of Microbiology and Biotechnology
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• 제8권4호
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• pp.318-324
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• 1998

A ${\beta}$-galactosidase with high transgalactosylic activity was purified from a Bacillus species, registered as KFCC10855. The enzyme preparation showed a single protein band corresponding to a molecular mass of 150 kDa on SDS-PAGE and gave a single peak with the estimated molecular mass of 250 kDa on Sephacryl S-300 gel filtration, suggesting that the enzyme is a homodimeric protein. The amino acid and sugar analyses revealed that the enzyme is a glycoprotein, containing 19.2 weight percent of sugar moieties, and is much more abundant in hydrophilic amino acid residues than in hydrophobic residues, the mole ratio being about 2:1. The pI and optimum pH were determined to be 5.0 and 6.0, respectively. Having a temperature optimum at $70^{\circ}C$ for the hydrolysis of lactose, the enzyme showed good thermal stability. The activity of the enzyme preparation was markedly increased by the presence of exogenous Mg (II) and was decreased by the addition of EDTA. Among the metal ions examined, the most severely inhibitory effect was seen with Ag (I) and Hg (II). Further, results of protein modification by various chemical reagents implied that 1 cysteine, 1 histidine, and 2 methionine residues occur in certain critical sites of the enzyme, most likely including the active site. Enzyme kinetic parameters, measured for both hydrolysis and transgalactosylation of lactose, indicated that the enzyme has an excellent catalytic efficiency for formation of the transgalactosylic products in reaction mixtures containing high concentrations of the substrate.

• 생물환경조절학회지
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• 제2권1호
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• pp.53-57
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• 1993

방울토마토에 적합한 수경재배방식에 관한 연구 결과, 담액수경에서 주경의 기부직경, 엽장, 엽폭, 화방길이 등의 생육이 가장 좋았으며, 암면재배와 NFT는 유사하였다. 개화시기와 과실의 착색일에 대하여는 각 방식마다 차이를 보이지 않았으나, 과실의 수확량은 담액수경에서 많았다. 건물율, 유기산, 경도, 당도 등은 담액수경에서 낮았고, 당산비와 vitamin C는 높아 담액수경에서 품질이 약간 우수한 것으로 나타났다. 따라서, 방울토마토의 여름재배에서는 담액수경방식이 바람직한 것으로 평가되었다.

• 한국식품조리과학회지
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• 제25권6호
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• pp.747-757
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• 2009

The purpose of this study was to enhance the quality of kochujang Apple juice was added to traditional Kochujang at 0%, 20%, 40%, 60 and 80%. Physicochemical and microbial characteristics were periodically investigated during at room temperature during a 90 day fermentation period. The moisture content of the apple Kochujang was higher than that of the control, while the salt content of the apple Kochujang was lower than that of the control, At first, the sweetness of the apple Kochujang showed no significant difference from the control; however, its sweetness increased during the 90 days. In all treatments, the pH value decreased during the fermentation period, while the titratable acidity increased during the fermentation period. Viscosity decreased greatly after 30 days. Sugar reduction was higher in the apple Kochujang than in the control, and its concentration increased with apple juice content. According to the analysis of free sugar, glucose, fructose, and maltose had an especially high ratio in the apple Kochujang. The organic acids detected in Kochujang were citric acid, malic acid, oxalic acid and lactic acids. The content of citric acid and malic acid were higher than the other acids in the apple Kochujang. L, a, and b values generally decreased during the fermentation period. When the Kochujang was made, the number of the total viable cells was $10^7\;CFU/g$. At room temperature, the number steadily increased up to the 30th day, then steadily decreased on the 90th day. After that, there was no significant change. The number of yeasts was $10^6\;CFU/g$ at the end of the 90th day. After the 90th day of fermentation, sensory results showed that the 60~80% apple juice Kochujang showed the best taste, appearance, texture, and overall quality.

• 한국식품저장유통학회지
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• 제4권2호
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• pp.155-162
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• 1997

This work was designed to determine the effect of steaming-Pretreatment on Physicochemical and functional properties of roasted Polygonatum odoratum roots. Steaming treatments led to some reduction in the contents of water solubles, such as total solid, reducing sugar and free-amino nitrogen of the unroasted samples. Moreover, roasting processing caused decrease in reducing sugar and free-amino acid, with increase in total soluble solid and browning color of the samples, which showed the dependence of steaming treatment as well as roasting temperature. Electron-donating ability and nitrite-scavenging ratio of the samples were also highly developed along with roasting processing at 17$0^{\circ}C$ within 35min. Considering the physicochemical and some functional parameters of water extracts of roasted samples, roasting at above 14$0^{\circ}C$ for over 55min or at 17$0^{\circ}C$ for around 35min was recommendable for the higher quality of Polygonatum odoritum tea, which conditions were similarly adapted for both steamed and unsteamed samples.

• 한국식품과학회지
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• 제17권6호
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• pp.442-446
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• 1985

저염산(低鹽酸), 저온(低溫)으로 분해(分解)한 아미노산(酸)간장 제조중(製造中) 질소이용률(窒素利用率), 단백분해율(蛋白分解率) 및 유리당(遊離糖)의 동향(動向) 등(等)을 검토(檢討)해 본 결과(結果)는 다음과 같다. 탈지대두(脫脂大豆) 3배량(倍量)의 6%염산(鹽酸)으로 $85^{\circ}C$에서 가수분해시(加水分解時) 65시간후(時間後) 질소이용률(窒素利用率)은 74.51%, 단백분해율(蛋白分解率)은 56.49%이고 유리당(遊離糖) glucose, galactose, arabinose, fructose, xylose 등(等)이 검색(檢索)되었다. $95^{\circ}C$에서 가수분해시(加水分解時) 50시간후(時間後) 질소이용률(窒素利用率)은 77.72%, 단백분해율(蛋白分解率) 64.04%이고 유리당(遊離糖)은 분해(分解) 5시간후(時間後)에는 상기(上記) 5 종(種) 유리당(遊離糖)이 동정(同定)되었으나 80시간후(時間後)에는 glucose만 검색(檢索)되었다. 탈지대두(脫脂大豆) 3배량(倍量)의 12% 염산(鹽酸)으로 $95^{\circ}C$에서 가수분해시(加水分解時) 50시간후(時間後) 질소이용률(窒素利用率)은 88.41%, 단백분해율(蛋白分解率) 69.47%이고 유리당(遊離糖)은 $20{\sim}35$시간후(時間後) 거의 전량(全量) 소실(消失)되었다. 가수분해중(加水分解中) galactose가 glucose에 비해 소실속도(消失速度)가 빨랐다.

• 한국산학기술학회논문지
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• 제20권2호
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• pp.535-542
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• 2019

본 연구는 각종 누룩으로 제조한 누룩소금들의 성분을 비교분석하여 누룩소금 제조시 필요한 기초자료를 확보하고 사용자의 요구에 맞는 누룩소금을 선택할 수 있도록 하는 것을 목적으로 하였다. 누룩종류로 이화국, 미인국, 백국, 입국을 선정하여 누룩을 제조한 후 특성을 파악하였고, 재료비율과 온도 등 동일한 발효조건하에 누룩소금을 제조 후 이화학적 특성을 분석하였다. 누룩소금 제조 시 pH는 발효전 6.2-6.5에서 발효 3일후 6.1-6.2로 떨어진 다음 이후에는 약간 높아졌다. 총산은 발효전 0.16-0.18에서 발효후 0.22-0.25로 증가하였으며 누룩 간 차이는 없었다. 당도는 발효 후 높아졌으며 입국으로 만든 누룩소금이 가장 큰 당도 증가를 보였다. 누룩소금의 염도는 발효 전 30-32에서 발효 후 37-44로 높아졌으며 입국의 증가폭이 가장 컸다. 누룩소금의 유기산은 acetic acid, oxalic acid, malic acid, lactic acid, citric acid 순으로 많이 검출되었다. 백국소금의 oxalic acid는 0.77 mg/mL으로 입국소금의 2.3배 많았고, succinic acid도 1.19 mg/mL로 백국소금이 가장 많은 것으로 나타났다. 한편 malic acid, lactic acid, acetic acid 및 citric acid는 각각 0.29 mg/mL, 1.48 mg/mL, 0.12 mg/mL로 입국소금이 가장 많은 것으로 나타나 입국으로 제조한 누룩소금이 다른 누룩으로 제조한 누룩소금 보다 부드러운 감칠맛이 더 좋은 것으로 나타났다.

• 한국식품영양학회지
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• 제11권4호
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• pp.402-408
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• 1998

A rapid processing method for fermented sauce of favorable flavor was investigated with low-usefulness marine resources. Hydrolyzed at optimal conditions for 6 hours usuing alcalase, and separated by molecularporous membrane. It's very effective for remove bitter taste at below M.W. 100 dalton, and effective at below M.W.500 dalton. Added 2% invert sugar in fermented sauce at below M.W.500 dalton, and thermal treatment at 100$^{\circ}C$ for 30 minutes were improved flavor. Chemical composition of fermented sauce using hair tail were 80.7% of moisture, 2.2% of carbohydrate, 1.8% of total nitrogen, 1.6% of amino nitrogen and pH was 6.5. The ratio of amino nitrogen in total nitrogen was 77.8%. And chemical composition of fermented sauce used gizzard shad, kangdale, pen shell and oyster were similar to fermented sauce used hair tail. Total nitrogen were above 1.8% and the ratio of amino nitrogen in total nitrogen was 77.7∼84.2% in all fermented sauce. Amino acid contents in fermented sauce used hair tail, gizzard shad, kangdale, pen shell and oyster were 4,318.1mg%, 4,681.3mg%, 3,156.2mg% and 4,175.0mg%, respectively. And the predominant free amino acid were glutamic acid, lysine and glycine in all fermented sauce.

• 한국식품영양과학회지
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• 제23권6호
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• pp.1027-1031
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• 1994

A method for the process of making fig conserves to prevent the denaturation of ficin (EC3.422.3) that is a proteolytic enzyme in fig (Fixus carica L. ) has been developed. The suutable composition ratio of materials such as, fig, sugar, citric acid and potassium sorbate, to make fig conserves was 1,000, 600 , 1.0 and 0.67g , respectively. to maintain the ficin activity, it was necessary that these materials were heated on 55$^{\circ}C$ and concentrated in the reduced pressure. At a result of sensory evaluation , meat treated with fig was the softest among samples. Then the treated beef with 55$^{\circ}C$ converse, 7$0^{\circ}C$ conserves, sugar and control have been shown the decreased rate respectively. There was significantly different in the effect of tenderness between each group(0.1%) . The nitrogen content of connective tissue was relatively low in the groups of the treated beef with fig and 55$^{\circ}C$ converses, 7$0^{\circ}C$ converses sugar and control , which was similar to the order of the ficin activity. This research revealed that the constituent protein of meat muscle was decomposed by ficin and its solubility was relatively higher than before.

• 원예과학기술지
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• 제34권3호
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• pp.396-404
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• 2016

In this study, four cultivars of strawberry commonly grown in South Korea, 'Daewang', 'Seolhyang', 'Maehyang', and 'Ssanta', were evaluated for several qualities, including the presence of phytochemicals, sugar content, organic acids, and fruit hardness. The plants were cultivated on a high-bench bed system in a plastic greenhouse and drip irrigated. Fruit samples were collected three times in February 2013 to analyze the fruit characteristics. We found that the fruit hardness of the 'Daewang', 'Maehyang', and 'Ssanta' cultivars was greater than that of 'Seolhyang', however 'Seolhyang' showed the highest moisture content of all the cultivars, indicating that fruit hardness was negatively associated with moisture content. Furthermore, 'Seolhyang' was found to have the highest levels of phenolic compounds and anthocyanins compared to the other cultivars. 'Maehyang' had the highest amount of total sugars. 'Seolhyang' and 'Maehyang' accumulated higher amounts of total organic acids. As a result, 'Daewang' and 'Maehyang' were expected to be preferred by consumers because they had the highest ratio of sugar to total acid in their fruit.

• 한국식품저장유통학회지
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• 제14권6호
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• pp.611-616
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• 2007

본 연구에서는 양촌 월하시 생감 및 곶감의 유용성분 및 이화학적 특성에 대하여 조사하였다. 월하시 생감과 곶감의 수분함량은 85.52, 47.36%, 조지방은 0.1, 0.13%, 조단백질은 0.30, 1.89%, 조섬유는 0.56, 2.0%를 각각 나타내었고, 수분활성도는 0.994, 0.838, pH는 5.68, 5.73, 당도는 12.6, $56.4^{\circ}Brix$를 각각 나타냈다. 색차계를 이용하여 측정한 생감과 곶감의 명도 L값은 외부가 47.58, 37.80, 내부는 66.55, 24.96을 각각 나타내었고, 황색도 b값은 외부가 73.40, 20.17, 내부는 26.55, 29.66을 각각 나타냈다. 유리당 함량을 HPLC로 측정한 결과 glucose와 fructose 만이 확인 되었다. 곶감에서 함유량이 월등히 높아 glucose는 생감보다 3.24배, fructose는 3.67배로 확인되었다. 아미노산을 분석한 결과 곶감에서 모두 17종이 확인되었다. 구성아미노산 중 전반적으로 glutamic acid, aspartic acid, histidine, arginine의 함량이 높게 나타났으며 valine, threonine, leucine, lysine, phenylalanine 등의 필수아미노산들이 골고루 검출되었다. 생감과 곶감의 총아미노산 함량은 각각 3,130.76 ppm과 12,849.33 ppm으로 곶감이 생감보다 4.1배나 높았다. 지방산 조성을 분석한 결과 myristic acid(C14:0), palmitic acid(C16:0), palmitoleic acid(C16:1), stearic acid(C18:0), oleic acid(C18:1), linolenic acid(C18:3) 등 14-15종이 확인되었으며, 이중 linolenic acid(C18:3)가 생감에 32.70%로, palmitic acid(C16:0)가 곶감에는 48.62%로 각각 가장 많이 함유되어 있었다. 무기성분을 AAS로 분석한 결과는 생감과 곶감의 나트륨은 0.60, 2.77 mg, 칼륨 190.49, 859.63 mg, 칼슘 11.73, 16.20 mg, 철 1.17, 3.17 mg, 그리고 인이 52.52, 84.90 mg/100 g 각각 검출되었다. 특히 무기물 중 칼륨과 인이 상당히 높은 함량 검출되었으며 곶감에서 그 함유량이 월등히 높아 칼륨은 생감보다 4.5배, 인은 1.6배로 확인되었다.