• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.207-215
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• 2012

Six different mashing types ((A) $koji$+purified enzyme, (B) $koji$+crude enzyme, (C) $koji$+$nuruk$, (D) $koji$+purified enzyme+$nuruk$, (E) $koji$+crude enzyme+$nuruk$, (F) purified enzyme+$nuruk$) had been established, according to fermentation agents and a mixing rate of rice $makgeolli$, in this study. The alcohol content was the highest in the mashing type (C), which was 13.6%, followed by (D) 13.5%, (A) 13.1%, (B) 12.9%, (E) 12.7% and (F) 12.1%. The reducing sugar content of (A) was the highest with 401.6 mg% and those of (B), (C), (D) and (F) were between 337.3- 380.9 mg%. The alcohol components were found and tended to increase during the fermentation. The oligo-saccharides content was the highest in (D) with 1251.3 mg%, which was followed by (E) 1,219.2 mg%, (C) 1,141.4 mg%, (A) 1,049.9 mg% and 973.8 mg% in (B). The total free amino acid was highest in (B) with 781.4 mg% and followed by (C) 703.2 mg%, (D) 702.6 mg%, (E) 678.7 mg%, (A) 630.4 mg% and (F) 328.7 mg% in order. There were 16 different types of volatile flavor components, in the mashing types (A) and (B), in addition to 15 different types of those in type (C), as well as 14 different types of those in (D), (E) and (F). There were significant differences in the overall preference between the type (A) and (C).

• Food Science and Preservation
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• v.18 no.1
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• pp.26-32
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• 2011

We added Nuruk at various proportions to brown rice Takju, and investigated the quality characteristics of vinegar produced in agitated culture and static culture. The more Nuruk was added, the higher the alcohol concentration. However, when over 30% (w/w) Nuruk was present, the increment in alcohol content was low (maximum 13.5%, v/v). A comparison of the quality of brown rice vinegar produced in agitated culture with that of vinegar produced in static culture showed that titratable acidity in agitated culture vinegar was highest after fermentation with 30% (w/v) Nuruk, at 5.97%. In static culture, the greater the amount of Nuruk added after 16 days of fermentation, the higher the titratable acidity of vinegar produced; this was true upon addition of either 30% (w/v) or 40% (w/v) Nuruk. Free amino acid levels increased in both agitated and static cultures as the level of added Nuruk rose. Moreover, brown rice vinegar produced in static culture had a higher level (7-30%) of total free amino acids than did vinegar produced in agitated culture. In particular, the level of gamma-amino butyric acid, a functional fortifier, was 3-5-fold higher in vinegar produced in agitated culture. The results thus indicate that both the amount of added Nuruk and the type of fermentation affected the level of free amino acid production. A static culture is expected to undergo changes in aroma and sensory characteristics during fermentation, indicating that further research on vinegars is required.

• Journal of the Korean Society of Food Culture
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• v.7 no.3
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• pp.245-252
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• 1992

The purpose of the study was to develop computer-based menu planning program for day-care centers maximizing food preference score among children and satisfying such constraints as expense, nutrients, and season. Children's preference about 142 menu items was surveyed among 382 children of day-care centers. A 16-bit personal computer compatible with IBM-PC/AT was used. The data base files were created by dBASE III Plus, and processing programs were created by using FORTRAN language. Children preferred bread or a la carte menu items to cooked rice in main dish category. Deep fat fried or stir-fried menu items were more preferred than kimchi or cooked vegetables in side dish category. Preference scores for menu items were influenced by cooking methods or main ingredients. The contents of the computerized system show that when the program runs, the user should type inputs of cycle, season, and menu pattern, then the computer lists a series of menu satisfying the criteria of constraints. The user can examine and select a set of menu from the menu lists. Menus are generated seasonally. Menu lists are generated weekly and monthly basis with the contents of menu items, preference scores and price. Nutrient reports are also generated on a weekly and monthly basis with the contents of calories, 12 nutrients and price. Recipes for each menu items are also generated.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.50-58
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• 2018

Elephant garlic (Allium ampeloprasum var. ampeloprasum), which belongs to the Alliaceae family along with onion and garlic, has a flavor and shape similar to those of normal garlic but is not true garlic. Additionally, its properties are largely unknown, and its processing and product development have not been reported. In this study, we focused on using elephant garlic to produce a new type of vinegar, for which the market is rapidly growing because of its health benefits. First, we evaluated the effects of elephant garlic addition on acetic acid fermentation of rice wine by Acetobacter pasteurianus. In contrast to normal garlic, for which 2% (w/v) addition completely halted fermentation, addition of elephant garlic enabled slow but successful fermentation of ethanol to acetic acid. Metabolite analysis suggested that sulfur-containing volatile compounds were less abundant in elephant garlic than in normal garlic; these volatile compounds may be responsible for inhibiting acetic acid fermentation. After acetic acid fermentation, vinegar with elephant garlic did not have any sulfur-containing volatile compounds, which could positively contribute to the vinegar flavor. Moreover, the amino acid profile of the vinegar suggested that nutritional and sensory properties were more enhanced following addition of elephant garlic. Thus, elephant garlic may have applications in the development of a new vinegar product with improved flavor and quality and potential health benefits.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.301-307
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• 2010

This study evaluates quality of Nuruk, which is a source material of Takju, collected in Daegu and Gyeongbuk and investigates fermentation characteristics of Takju made of it. Totally 7 types of Nuruk were examined and their pH and titratable acidity were 5.4~5.9 and around 0.1%, respectively. Saccharifying activity was high in D, F, G, A and E Nuruk by recording over 300 mg%. Lactic acid bacteria count was the highest in G Nuruk with $3.78\times10^8$ and yeast and total microbe count recorded the highest levels, $3.78\times10^8$ and $3.47\times10^8$, respectively in B Nuruk. When quality characteristics of Takju made of each type of Nuruk were compared, alcohol content was the highest in G Nuruk by recording 19.0% and titratable acidity was 0.44~0.86% in all samples. Hunter's color, brown color and turbidity showed different levels according to types of Nuruk and all lactic acid bacteria, yeast and total microbe counts were the highest in A and E Nuruk. For alcohol components, E and G Nuruk showed high fusel oil content levels and methanol and fusel oil contents of all samples were suitable as standards, respectively. The total organic acid content was the highest in B Nuruk at about 4,000 mg% and it was 2,000 mg% and around 1,000 mg% in A, E, F and G Nuruk and C and D Nuruk, respectively. The content of total free amino acid was the highest in B Nuruk at 3,676 mg% and it was observed to be 1,890, 1,676 and 1,531 mg% in G, E and C Nuruk in that order, respectively. Sensory preference of subjects in their 20s was high overall in G and C Nuruk and that of those in their 40s was high in F and C Nuruk. From all of these results, the types of Nuruk largely affected quality and components of Takju and an appropriate method to consider useful purpose is needed.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.6
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• pp.853-862
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• 2011

We reproduced and investigated the quality characteristics of Samhaeju (one type of Korean traditional rice wine), which has been described in ancient documents. During fermentation, the room temperature was $9.1{\sim}25.0{\circ}C$, and each treatment's material temperature was $11.7{\sim}23^{\circ}C$. As the fermentation proceeded, the pH rapidly decreased (initial pH was 6.6~6.9) and rose gradually from the 18th day. Titratable acidity and amino acidity slowly increased in general. Regarding soluble solid contents, there were various change patterns depending on the production method, and they were affected by initial room temperature. In the treatments using 1 (Sang-ga-yo-rok), 3 (Eum-sik-di-mi-bang), 7 (Jo-sun-mu-ssang-sin-sik-yo-ri-je-beop), 8 (Sang-ga-yo-rok $15^{\circ}C$), reducing sugar contents decreased rapidly after 1st mashing day and then increased slightly after 2nd mashing. The alcohol content increased as the fermentation proceeded, and most of the treatments produced 1/2 the amount of total alcohol content before the 2nd mashing day, followed by a slight increase until the end of fermentation (about 100 days from the 2nd mashing day). In the sensory evaluation, Samhaeju using methods 2, 4, 5, and 6 got high scores and had much reducing sugar contents than other treatments. Among the seven manufacturing processes, method 2 was relatively simple and got the highest score in the sensory evaluation. Therefore, method 2 would be suitable for industrialization and popularization of Korean traditional alcoholic beverage.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.6
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• pp.477-484
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• 2016

Small industrial appliances such as fan, audio, electric rice cooker mostly consist of ABS, PP, PS materials. In colored plastics, it is possible to classify by near infrared(NIR) spectroscopy, while in black plastics, it is very difficult to classify black plastic because of the characteristic of black material that absorbs the light. So the RBFNNs pattern classifier is introduced for sorting electrical and electronic waste plastics through LIBS(Laser Induced Breakdown Spectroscopy) spectrometer. At the preprocessing part, PCA(Principle Component Analysis), as a kind of dimension reduction algorithms, is used to improve processing speed as well as to extract the effective data characteristics. In the condition part, FCM(Fuzzy C-Means) clustering is exploited. In the conclusion part, the coefficients of linear function of being polynomial type are used as connection weights. PSO and 5-fold cross validation are used to improve the reliability of performance as well as to enhance classification rate. The performance of the proposed classifier is described based on both optimization and no optimization.