• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.926-931
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• 2011

Among various techniques for hydrogen production from organic wastewater, a dark fermentation is considered to be the most feasible process due to the rapid hydrogen production rate. However, the main drawback of it is the low hydrogen production yield due to intermediate products such as organic acids. To improve the hydrogen production yield, a co-culture system of dark and photo fermentation bacteria was applied to this research. The maximum specific growth rate of R. sphaeroides was determined to be $2.93h^{-1}$ when acetic acid was used as a carbon source. It was quite high compared to that of using a mixture of volatile fatty acids (VFAs). Acetic acid was the most attractive to the cell growth of R. sphaeroides, however, not less efficient in the hydrogen production. In the co-culture system with glucose, hydrogen could be steadily produced without any lag-phase. There were distinguishable inflection points in the accumulation of hydrogen production graph that resulted from the dynamic production of VFAs or consumption of it by the interaction between the dark and photo fermentation bacteria. Lastly, the hydrogen production rate of a repeated fed-batch run was $15.9mL-H_2/L/h$, which was achievable in the sustainable hydrogen production.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.649-654
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• 1989

The color distribution of fish sauces was studied by using the change in log absorbance per 100nm as a parameter of color tone. A linear relationship was found between the logarithm of absorbance (log A) and wavelength at 450 nm to 650 nm in the color of fish sauces. Change in log A per 100nm $({\Delta}A)$ in the color of the fish sauce products was in the range of 0.55 to 0.59. Absorbance at 450 nm (A 450) of the fish sauce treated with soy sauce koji was high in comparison with A 450 of the fish sauce treated by pronase and control. The color of fish sauces treated with soy sauce koji was dark reddish orange, and was similar to the color of soy sauce. A 450 of every fish sauce increased with the progress of fermentation but ${\Delta}A$of the fish sauces slightly increased at the beginning of fermentation and then decreased at the end of fermentation. In the results of sensory evaluation for the flavor of fish sauce products, the fish sauce product treated with soy sauce koji that 20% salt was added at the first stage was the molt desirable in the strength of flavor, tastefulness and after taste, and the fish sauce was also the best in acceptability.

• Journal of Dairy Science and Biotechnology
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• v.29 no.1
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• pp.23-31
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• 2011

Domestic dairy industry is now standing at the crossroad for planning next fifty years, mainly because economic and environmental situations surrounding Korean peninsula are fast changing. For the aspects of dairy consumption, fresh milk consumed less, while consumption of the other milk and dairy products is slightly increasing every year. In 2010, it is approximately estimated that 1,939,000 tons of raw milk was used and the supply would be short by about 35,000 tons, based on the amounts in the previous year. Currently, multilateral negotiations against US and EU are underway. When it will be in effect in the future, significant damage would be expected in the dairy and livestock sectors, leading to cut domestic milk supply. Quality of farm-gate milk is graded as 1A on average 90% or more, loaded with very low in microbial and somatic cell counts. Therefore, policy implications have to be placed toward switch currently the UHT processing method to Pasteurization or the LTLT technology, by which natural flavors and nutrients in milk mostly remain after heat treatment. Domestic cheese products comprise only 10% and the rest is occupied by the various kinds of imported natural products. The market size keeps increasing up to 65,423,000 tons last year. When it comes to vitalization of our natural cheese industry, cheese whey, which is a main by-product in cheese manufacture, is a critical issue to be solved and also "On-Farm Processing" would be combined with a growth of big dairy companies when few immediate issues among the relevant regulations will be eased and alleviated in the near future. Fermented milk market is recorded as a single area of gradual increase in the past 10 years, Korea. Fermented yogurts with health claims targeted stomach, liver, and intestine are popular and has grown fast in sales amounts. In this context, researches on beneficial probiotic lactic acid bacteria are one of the important projects for domestic milk and dairy industries. Labelling regulations on efficacy or health-promoting effects of functional dairy products, which is the most important issue facing domestic dairy processors, should be urgently examined toward commercial expression of the functionality by lawful means. Colostrum, a nutrition-rich yellowish fluid, is roaded with immune, growth and tissue repair factors. Bovine colostrum, a raw material for immune milk preparations and infant formula, can be used to treat or prevent infections of the gastrointestinal tract. Nanotechnology can be applied to develop new milk and dairy products such as micro-encapsulated lactase milk for consumers suffering lactose intolerance. Raw milk is suggested to be managed by its usage in the processing line because imbalance of supply and demand is structural problem in every country and thus the usage systems as in the advanced dairy countries is worth of bench-marking to stabilize milk supply and demand. Raw milk produced is desirable to divide into the three parts; domestic, import, and buffering purposes. It is strongly recommended that a domestic dairy control center as an institutional framework should be urgently established as is Dairy Board in New Zealand and Australia. Lastly, government policy should be directed to foster the highly-educated people who are majoring in Dairy Sciences or working in the dairy industry by means of financial support in studying and training abroad as well.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.2
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• pp.97-103
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• 1975

In order to use the glutamic acid fermentation residuum in agriculture effectively, comparison experiments of the residua liquid and dried solid, and compost on radish (Raphanus Sativus) and chinese cabbage (Brassica chinesis) were carried out, together with an investigation on some physical property changes of soil brought about by the use of the residua and compost. 1. An equal or somewhat superior effect of the glutamic acid fermentation residua solid and liquid, to urea was observed. 2. Both residua liquid and dried solid, tended to acidify soil and the tendency was observed to be somewhat servere in the latter. 3. The liquid fermentation residuum compounded with minor elements such as iron, manganese, zinc, copper and boron increased the yield of chinese cabbage compared with the liquid residuum alone. 4. Not only as a N, K fertilizer, the liquid residuum of glutamic acid fermentation could also be used as a source for liquid or solid compound fertilizer.

• Journal of Dairy Science and Biotechnology
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• v.40 no.3
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• pp.93-102
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• 2022

This study was conducted using response surface methodology (RSM) to elucidate fermentation conditions that will optimize ACE inhibitory activity using Lactiplantibacillus plantarum K79. Four independent variables [skim milk (with 1% added glucose) concentration (6%-14%), incubation temperature (32℃-42℃), incubation time (8-24 h), and amount of added starter (0.02%-0.2%)] were evaluated using five-level central composite design and response surface methodology to determine the optimum fermentation condition. The dependent variables were angiotensin converting enzyme (ACE) inhibitory activity (the value obtained from 102 diluted supernatant), and pH. The respective coefficients of determinations (R²) were 0.791 and 0.905 for ACE inhibitory activity and pH. The maximum ACE inhibitory activity was 90% under the following conditions: 10% skim milk (with 1% added glucose) concentration, 37℃ incubation temperature, 17.8 h incubation time, and 0.2% added starter. Based on the RSM, using predicted best ACE conditions for fermentation of 13.49% skim milk (with 1% added glucose) with 0.0578% starter at 33.4℃ for 21.5 h, the predicted ACE inhibitory activity and pH values were 86.69% and 4.6, respectively. Actual ACE inhibitory activity and pH values were 85.5% and 4.58, respectively

• Food Industry And Nutrition
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• v.7 no.3
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• pp.35-38
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• 2002

본 연구에서는 과실을 이용한 기능성 음료를 제조하기 위해 여러 가지 과즙을 이용하여 kefir 음료를 제조해 보았다. pH는 발효동안 감소하여 pH $4.0\sim4.2$를 나타내었으며, 숙성 후 pH $3.8\sim4.2$로 나타났다. 총산은 발효와 숙성과정 동안 지속적으로 증가였고 시유와 전지유에 startar를 5% 접종했을 때 총산은 0.8, 1.1로 나타났으며, 6% 접종구간은 1.5, 1.3으로 각각 나타났다. 발효초기 당도는 $11.7\sim11.2Brix$에서 발효 12시간 후에 $6\sim7Brix$를 떨어졌으나 숙성 동안에는 거의 변화가 없었다. 알콜함량은 $0.10\sim0.14%$로 미량이 생성되는 것을 알 수 있었다. 점도는 숙성 후 점도는 $2395\sim2488cP$로 시판요구르트 보다 낮은 점도를 나타내었는데 이것은 젖산발효에 관여하는 균주 차이로 생각된다. 관능검사 결과 사과농축액 35% 첨가구간은 향, 입안촉감, 전반적인 기호도에 높은 수치를 나타내어 선호도가 더 놓은 것으로 생각된다 따라서 kefir 발효액은 시판 요구르트와 품질이 비슷하여 음료제조에 적합한 것으로 생각되며, 과실을 이용하여 kefir 음료를 제조할 수 있는 것으로 생각된다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1415-1422
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• 2014

Hot water extraction concentrate was prepared from Alliun hookeri root (AHR) to evaluate its applicability to yogurt. The highest antioxidant activity of hot water concentrates was obtained under extraction conditions of 4 hr at $95^{\circ}C$. Antioxidant activities measured by DPPH radical assay, ABTS radical cation assay, reducing power, and cheating activity were highly correlated with total phenolic (89.51 mg/g) and total flavonoid (52.71 mg/g) contents, with R values of 0.94 and 0.96, respectively. Yogurt was fermented with a commercial lactic acid bacteria mixed strain (Yo-mix$^{TM}$ 305) for 10 hr at $42^{\circ}C$ after addition of 0~10% (w/w) hot water concentrates from AHR to yogurt base. As fermentation proceeded, pH and $^{\circ}Brix$ of yogurt decreased from 6.57~6.60 to 4.34~4.51 and from 8.10~8.90% to 4.60~5.25%, respectively, whereas titrate acidity, viscosity, and viable cell numbers increased from 0.22~0.23% to 1.01~1.10%, from $0mPa{\cdot}s$ to $202.55{\sim}290.50mPa{\cdot}s$, and from 6.40~6.80 log CFU/mL to 8.60~9.20 log CFU/mL, respectively. There was no significant difference in any sensory attribute between the control and 2.5% addition group, suggesting that 2.5% hot water concentrate from AHR could be used to manufacture yogurt.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.889-893
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• 2016

This study was carried out to investigate the physicochemical and fermentation properties of yogurt made from high pressure processing (HPP) treated milk. Raw milk and commercial yogurt starter were used to make yogurt. Raw milk was HPP treated at 350 or 450 MPa (HPP 350 or 450) for 15 min or heat treated at $80^{\circ}C$ for 10 min. The numbers of lactic acid bacteria of the HPP treated group (HPP yogurt) rapidly increased during 2~4 h, whereas there was not significant difference from control (P<0.05). Titratable acidity of all samples increased, and pH decreased during storage from 0.99 to 1.24%, as well as from 4.59 to 4.20, respectively. It is confirmed that these values are in general ranges for yogurt. Control showed higher viscosity than HPP 350. Syneresis was significantly lower than that of the control (P<0.05). Based on the data obtained from the present study, HPP treatment was effective to enhance the quality of yogurt.

• The Journal of the Korea Contents Association
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• v.5 no.6
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• pp.163-171
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• 2005

Many food companies cooperate with the existing food until it reaches from the start of the 90s recently. which began to develop suitable new functional foods in the characteristic of each product So that consumers' consciousness may also get interested in the functional foods with which a as specific ingredient and as specific as possible are expected while the expectation for health and a long life becomes high. from which it consisted of and the propriety of functionality became the important point of a new-product-development strategy. A packing design also takes the advantage of development of such functional foods. therefore the seen research, with general consideration of such functional foods Who is going to investigate to the product communication-of-information method and differentiation strategy of more desirable functional foods by analyzing and seeing the functional characteristics which each product has to the fermented milk enjoyed and drunk, and these expression strategies.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.200-206
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• 2005

This study was performed to develop a functional stirred yoghurt prepared from skim milk added with loquat(Eriobotrya japonica Lindley). Skim milk containing $15\%$ loquat extract was fermented by the mixed strains of Streptococcus thermophilus and Lactobacillus acidophilus, and then loquat flesh and oligosaccharide were added to the yoghurt base. Sensory scores of the stirred yoghurt containing $15\%$ loquat flesh and $20\%$ oligosaccharide were higher than other groups in sweet taste, sour taste and overall acceptability. When the levels of oligosaccharide of the stirred yoghurts added with $15\%$ loquat flesh were increased, the L value(brightness) and a value (redness) of the stirred yoghurt decreased, but the b value(yellowness) increased. The hardness, springiness, cohesiveness, gumminess and resilience of the $15\%$ loquat flesh stirred yoghurt added with $20\%$ oligosaccharide were higher than others.