• Food Science of Animal Resources
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• v.23 no.3
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• pp.262-268
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• 2003

Kefir is a traditional fermented milk in Caucasusian area and is made mainly of milk fermented with lactic acid bacteria and yeasts. Six typical kefir grains were selected from ten kefir grains collected from different locals in Korea. Kefir grains were gelatinous in texture and had various shapes of villi, grapes, leaves, hulled millets, and towels. To investigate predominant microflora of kefir grains, SPC, MRS, M17, Rogosa, and APT agar media were used for viable cell count MRS, SPC, and Rogosa media were most acceptable for bacterial cell counts of the selected kefir grains. From one or two of the SPC agar plates which contained around 25∼50 colonies, all grown colonies were isolated and identified. Most predominant bacteria was identified as Lactobacillus fermentum by API 50 CHL kit. The proportions of Lb. fermentum and Lb. brevis among the total identified bacteria were around 41~88% and M4%, respectively. To select the best preservation method for kefir grains, refrigeration, freezing, and freeze drying were compared. Freeze drying was found most suitable for the preservation of kefir grains, based upon their acid-producing activities and production of off-flavors.

• Food Science of Animal Resources
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• v.33 no.4
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• pp.542-548
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• 2013

This study was conducted to investigate effect of psychrotrophic bacteria on the quality of raw milk. Acinetobacter genomospecies 10 was selected as lipolytic species, and Serratia liquefaciens as proteolytic species. Lipase present in inoculated raw milk with Acinetobacter genomospecies 10 did not affect total solid and fat contents. However, the free fatty acid (FFA) content, especially short chain FFAs, of milk with Acinetobacter genomospecies 10 was dramatically increased. FFAs produced by lipolysis of milk fat are important in flavor of dairy products, excessive lipolysis occurring in milk and dairy products could cause off-flavor, and produced FFAs may have an underiable effect on their flavor. In addition, protease influenced the quality of inoculated raw milk with Serratia liquefaciens. In degradation patterns of casein by SDS-PAGE analysis from inoculatred raw milk with Serratia liquefaciens, casein content was gradually decreased during storage at $4^{\circ}C$, and extensive degradation of $\kappa$-casein was observed on the storage day of 13. The free amino acids such as leucine, valine, arginine, and tyrosine were dramatically increased, which causes bitter taste in raw milk. These excessive peptides in dairy products, produced by psychrotrophic bacteria, can be possible to develop off-flavors and be responsible for gelling of milk by degradation.

• Korean Journal of Food Science and Technology
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• v.7 no.2
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• pp.61-68
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• 1975

This study was conducted (1) to isolate the film-forming yeast from the commercially available soy sauce, (2) to identify the state of soy sauce fermentation by the use of yeasts, (3) to confirm characteristics of yeasts. The result were as follows. 1. These yeast strains in the soy sauce fermentation test showed full fermentation of whole sugar content, reduction of the pure extract and relative reduction in total nitrogen. Soy sauce color was somehow faded to lower the stability of soy sauce. 2. In anti-fungal activity test butylparaben at a higher level 60 ppm., sodium propionate 2,400 ppm, sodium benzoate 800 ppm., menadion 165 ppm, showed their anti-fungal effect, while alcohol did not show the effect in the 3% additive group. 3. The optimum sodium chloride concentration for these strains in the 2% G.Y.P. medium was 5% and optimum temperature was $30^{\circ}C$. The extinction temperature was $62^{\circ}C$ for strain No-1 and No-3, and was $65^{\circ}C$ for No-2 and No-4. 4. The film-forming soy sauce turned out in the gas chromatogram to possess much flavor of low boiling point as compared with the standard. These flavors were considered due to flavor spoilage of the soy sauce. 5. These isolated yeasts were identified Saccharomyces rouxii (film-forming yeast) in the Lodder's taxanomic study.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.615-623
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• 1998

The garlic juices were extracted and concentrated by heating at $90^{\circ}C$, by using a rotary vacuum evaporator at $45^{\circ}C$, or by freezing at $-50^{\circ}C$ until the volume was reduced to 70% of the original volume. The concentrated juices were kept at $4^{\circ}C\;or\;25^{\circ}C$ for 60 days and the changes of bacteria and color were monitored every 10 days. Flavors of the raw garlic juices, concentrated garlic juices, and garlic powder by hot-air drying were analyzed monthly using GC and GC/MS. The CFUs/mL of mesophilic and psychrotrophic bacteria in the garlic juice concentrated at $90^{\circ}C$ were lower about 1 to 2 log cycles than those of other concentrated juices. Hunter L, a, and b values in the raw garlic raw juice and the juice concentrated at $-50^{\circ}C$ significantly increased at the beginning of storage, in particular, when they were stored at $25^{\circ}C$. The garlic juice concentrated at $45^{\circ}C$ showed relatively low L value but the juice concentrated at $90^{\circ}C$ showed high a value. The main peaks in chromatograms of volatile components identified by GC/MS were 3,3'-thiobis-1-propene, di-2-propenyl disulfide, 3-(methylthio)-1-propene in the raw garlic juice and the concentrated juices, and the juices concentrated at $45^{\circ}C\;or\;-50^{\circ}C$ showed relatively high preservation of garlic flavor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.151-156
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• 1985

In order to develop a sanitary and economic storage method for chicken carcass by gamma-irradiation, the samples irradiated with 5 to 10 kGy were stored at 3 to $4^{\circ}C$ for 41 days, and the changes in ordour, appearance and the cooking guality of stored samples were determined. The nonirradiated samples which stored for more than 7 days were not tested because of microbial spoilage on the chicken carcasses. However, the quality of irradiated groups of 5 to 10 kGy was similar to that of fresh chicken for about 15 days though it deteriorated slightly after 20 days, however, they were still acceptable to eat each after 27 days of storage. The overall acceptability, flavor and texture was not significantly different in the samples of nonirradiated those of irradiated immediately and those of irradiated and then stored for 15 days when they were prepared for Sam Gei Tang arid steamed chicken. The acceptibility of Sam Gei Tang prepared with chickens after 15 days of the storage, the irradiated groups of 8 and 10 kGy showed a similarity to the chickens prepared immediately after slaughter. In steamed chickens prepared with the samples stored for 15 days texture of the irradiated group was superior to that of the nonirradiated fresh chicken, and there were no statistical differences in the flavors between each group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.450-457
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• 2011

Roasted soybean flour (RSF) and mixed cereals were fermented by the solid state fermentation using Bacillus subtilis HA to optimize the production of biologically active compounds. The RFS fermented with 52.7% moisture content showed higher production with protease activity of 42.6 unit/g and 10% mucilage content after fermentation for 24 hr. Tyrosine content and protease activity after 48 hr fermentation time were the highest values with 445.5 mg% and 55.1 unit/g, respectively. However, the wholesome fermented RSF (FRSF) was obtained by fermentation for 24 hr because of the production of unpleasant flavors after fermentation for 48 hr. The RSF fermented with various types and contents of cereals has no effects on tyrosine content and protease activity. However, the addition of brown rice significantly increased mucilage content, especially indicating 24.55% at the addition of 80% (w/w). For addition of barley, fibrinolytic activity was increased to 11.82 unit/g by the fortification of 60% barley. It is concluded that biologically active compounds including fibrinolytic activity and mucilage content in FRSF were dependent upon the type and content of various cereals.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.5
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• pp.397-406
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• 2004

The purpose of this study was to analyze women's consumption and preferences of the Korean traditional drinks. For this purpose, 205 women aged between teens and 60s living in Seoul were sampled randomly for a questionnaire survey conducted from August 21 to 27, 2003. The results of this study were summarized as follows: The percentile of age groups accounted for 15.6% of the subjects in their teens, 19.5% in 20s, 18.0% in 30s, 20.5% in 40s, 13.7% in 50s, and 12.7% in 60s, respectively. On the other hand, those who graduated from colleges accounted for most (49.8%) of the subjects, those employed by companies for most (23.9%) and those earning 2 million wons or more for most (40.5%). Subjects' preferences about the traditional drinks were as follows: The most popular traditional drink across all age groups was Sikhe (29.8%: fermented rice drink), followed by Sujonggwa (10.7%: dried persimmons punch) and green tea (8.8%). Most of those in their teens and 60s consumed the drinks to relieve from the thirst, while those between 20s and 50s to be healthy. The majority (31.7%) of the subjects were consuming the traditional drinks once or twice per week. Those in their teens and 40s consumed the drinks between 3 and 5 o'clock in the afternoon, while those in their 20s, 30s and 50s as they want, and those in their 60s after exercise and as they pleased. 63.4% of the subjects across all age groups bought the drinks at supermarkets, and 60.5% of them were consuming 200ml each time. The reasons of subjects' preferences of the traditional drinks were as follows: The most important factor perceived by all age groups was taste (61.0%), followed by nutrition (15.6%). The most preferred point of taste was 'light' (51.7%). Those in their teens preferred the drinks without grains, while the other age groups preferred the drinks with some grains. Those in their teens preferred canned drinks, while the other age groups preferred the bottled drinks. Consumers' desire for improvement of traditional drinks were as follows: Those in their teens and 20s were satisfied with the current prices of the drinks, while the other age groups hoped for lower prices. On the other hand, those in their 50s answered that the drinks should not be sweet, while the other age groups hoped that the tastes of the drinks would be improved in diverse ways. 53.2% of the consumers hoped that the flavors of the traditional drinks would be diversified. 67.3% of them hoped that the traditional drinks would be improved to be functional drinks, while 54.6% of them hoped that the drinks would be processed in a more hygienic way.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.4
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• pp.334-345
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• 2016

This study conducted surveys on perception and utilization of Korean soybean paste targeting 493 women from their 20s to 60s residing in Daegu. Most subjects married (75.3%), were part of a nuclear family (84.8%), had more than a high school diploma (95.8%), had a career (47.9%), lived in an apartment (68.4%), had a total household income of 5 million won or more (38.1%), and had monthly food expenses more than 0.5 million won and less than 1 million won (42.2%). Regarding perception, 'rich nutrition' was the most commonly held perception in subjects in their 60s (4.4), followed by 'good taste' in subjects in their 40s (4.3). Regarding reasons for consumption 'healthy' was highest in subjects in their 60s (47.3%) and 40s (45.6%) and 'delicious' in subjects in their 20s (56.1%). Regarding how to make it, subjects in their 60s responded 'know for sure' (57.1%), while only 2% of 20s responded the same. Subjects in their 50s and 60s had a higher ratio of answering 'know' while 20s and 30s 'don't know', For preparation methods, subjects in their 20s (53.1%) and 30s (41.4%) answered 'buy at the market', subjects in their 40s (68.9%) 'get from family or relatives' and subjects in their 60s (47.3%) 'make by one's own'. For preservation method, subjects in their 20s and 30s answered 'preserve in refrigerator', the 60s tend to answer 'preserve in jangdokdae'. Buying at the market was most common in subjects in their 20s (36.1%) and 30s (28.5%) and the reason was 'convenient' (39.6%). The place of purchase was 'in large supermarket or department store' (78.5%). For the future consumption pattern, 'increase in consumption of commercialized product (44.0%)', subjects in their 60s answered 'keep making at home' while subjects in their 30s and 40s answered 'keep making at home or buying product half and half'. According to the above study results, women living in Daegu region were aware of excellence of traditional soybean paste. However, due to changes in residential circumstance and lack of knowledge about the recipe, they did not make. They receive soybean paste t from family, relatives or bought in the market, which indicates the continuous decrease in home-made soybean paste. Therefore, due to the expanding social participation of women, the product market is expected to increase. I think it is important to develop traditional commercial soybean paste in the traditional way to improve the traditional flavors.

• Journal of the Korean Home Economics Association
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• v.40 no.4
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• pp.167-178
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• 2002

This study was carried out to compare the meal management attitudes among the mothers(41 years of age) who had middle school students between in industrial complex and in non-industrial complex. The subjects of each group were composed of 192 mothers Living in Ansan city in Korea, and this study was performed by self-administered questionnaire. The results of the present study were as follows: (1) Monthly family income and education level of parents were lower in industrial complex-family(ICF) than in non-industrial complex-family (NICF). The mean age of mothers and family size were similar in two groups, but the frequency of mothers employed was higher in ICF than in NICF Most mothers in ICF worked as a manual- or skilled-laborer. (2) The mothers in ICF tended to have less positive attitude in sewing balanced meals to their families than those in NICF. The score of nutritional knowledge was lower in mothers in ICF than those in NICF. (3) The percentage of expense for purchasing staple foods to total expense of foods tended to be higher in ICF than in NICF. Engel's coefficient was higher, and the frequency and expense for eating out was lower in ICF than in NICF (4) The mothers in ICF did not try to use their time and energy efficiently for meal management. (5) The mothers in ICF were less active in sewing the pleasurable meals including the provision of various cooking methods, flavors, and temperatures, to their families, than those in NICF. Above findings show that family environment such as industrial complex-families and non-industrial complex-families influences the meal management attitudes of mothers. The mothers in ICF had a less positive altitudes for scientific meal managements than those in NICF even though they had the limited resources including money, time and energy for meal management because most mothers in ICF had a job that were paid low salary and finished irregularly or late. Therefore, these results underscore the need to provide the sound nutritional education for the mothers in ICF with respect to reasonable meal management for 'optimal nutrition of family'. In addition, the government should try to make the various welfare policies to improve nutritional status of low income famines including the poor industrial complex-families.

• Culinary science and hospitality research
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• v.21 no.1
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• pp.267-280
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• 2015

This study was carried out to evaluate the quality characteristics of Takju, Yakju, Spirit made by various cereal Nuruks which were made by Jokuk(whole wheat), Bunkuk(wheat flour), Maekkuk(whole barley). pH, Brix, cell number of yeast, alcohol content, flavors, organic acid, and sensory evaluation of brews were employed to analyze current study. Results showed that pH value of brews during fermentation decreased, while Brix value increased. In addition, alcohol contents increased up to 11 day's fermentation, but there were no significant differences among Jokuk, Bunkuk and Maekkuk(p<0.05). Cell numbers of yeast dramatically increased up to 5 day's fermentation, and then decreased. After 13 day's fermentation cell numbers of yeast were similar among Jokuk, Bunkuk and Maekkuk. In terms of analysis of flavor components, acetone and n-amyl alcohol were not detected in all brews, however fusel oil level was 494.65 mg/L in Maekkuk, and 525.4 mg/L in Bunkuk. Lactic acid showed the highest level in organic acid analysis. Furthermore, Jokuk and Maekkuk showed highest score in Takju, Maekkuk showed highest score in Yakju in sensory evaluation, although Jokuk, Bunkuk, and Maekkuk revealed similar score in spirit.