• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.431-437
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• 2015

In this study, high-acidity cider vinegar (HACV) was produced by alcoholic and acetic acid fermentation of apple concentrate without any nutrients and then the optimum alcohol concentration was determined through a qualitative study. HACV was fermented with different initial alcohol concentrations (6-9%) during the process of acetic acid fermentation. The highest content of reducing sugar, organic acids, and free amino acids was observed at 6% of initial alcohol concentration. Approximately 20 types of volatile compounds were identified by solid-phase microextraction (SPME) and GC-MS. The total volatile content was the highest at 6% of initial alcohol concentration, and the acid content was the lowest at 9% of the initial alcohol concentration. The HACV produced by a two-stage fermentation process was qualitatively better than commercial HACV presenting the highest value at 6% of initial alcohol concentration. Malic acid, aspartic acid, and hexyl acetate were selected as quality index components of HACV production by two-stage fermentation on the basis of correlation between their physicochemical properties and the sensory attributes of HACV.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.5
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• pp.667-676
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• 2012

This study was conducted to investigate the quality characteristics and antioxidant activity of Kochujang following the addition of deodeok (Condonopsis lanceolata) powder. To accomplish this, 1%, 3% and 5% deodeok powder was added to Kochujang and the samples were then incubated at $30^{\circ}C$. during which time the general ingredients, water content, acidity, salinity, reducing sugar content, amino-nitrogen content and DPPH were analyzed at intervals of about two weeks. The water crude protein, crude fat and ash content were 3.61%, 8.44%, 4.62% and 8.85%, respectively. The initial acidity was 3.23~3.97%, and this increased to 4.39~44.86%. highlight please clarify this, I cannot infer your intended meaning; however, this can likely be deleted. The salinity was 7.42~7.73%, and 5% with deodeok powder producing the lowest content and showing a tendency to decrease during the storage period. The early amino-nitrogen content was 274.0~333.1%, with higher nitrogen contents being associated with large amounts of deodeok powder. The amino-nitrogen content during the storage period increased to the 4th week, then decreased. Additionally, the a value decreased sharply during the 4-week storage period. Addition of large amount of deodeok powder significantly improved the free radical scavenging activity. The free radical scavenging activity of 1%, 3% and 5% deodeok powder was higher than that of Kochujang throughout the maturation period. Overall, the results of this study indicate that there is the potential to develop functional foods by the addition of deodeok.

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.53-58
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• 1983

Sik-hae is a traditional Korean fermented fish product which is made from flat-fish, garlic, salt, red pepper and millet. The changes in chemical composition, pH, acidity and the contents of Amino-N, VBN, TMA and organic acids were investigated during the fermentation of Sik-hae. The changes in the microflora, enzyme activity and the sensory quality including textural characteristics were also evaluated. The changes in the contents of crude protein, crude fat and moisture during Sik-hae fermentation were negligible. The pH of the product tended to decrease in the course of fermentation and it showed the minimum value of 4.5 after 7 days of fermentation. On the other hand the acidity continued to increase up to 2300mg % by 4 weeks of fermentation. Lactic acid was the major organic acid. The content of Amino-N in sik-hae gradually increased up to 673.6mg % by 2 weeks of fermentation, and then slightly decreased. The content of VBN increased rapidly during the first 2 weeks of fermentation, while little changes in TMA content was observed. The number of proteolytic bacteria increased slightly for the first 2 weeks and then rapidly decreased. The number of yeast and acid forming bacteria increased rapidly from the 4th day to the 14th day of fermentation and then decreased. Both lipase and protease activities showed the maximum at the 11th day of fermentation. The texture softening of the fish occurred after 1 week of fermentation and the adhesiveness appeared after 2 weeks of fermentation. Summarizing these results, the optimum fermentation time for Sik-hae from flat fish were 2 weeks at 2$0^{\circ}C$ and the quality of the product could be kept for up to 4 weeks in refrigerator.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1077-1085
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• 1998

The effects of yeast on the fermentation of kimchi were investigated. The treatments were divided into two groups; yeast treatment during salting of Chinese cabbage(YS) and yeast treatment added in kimchi preparation(YF kimchi). The edible periods of the kimchi after yeast treatment during salting (YS kimchi) was extended 4~5 days by the results of pH, acidity, sensory quality. The activities of amylase, polygalacturonase and galactosidase of YS kimchi were retained at low levels compared to non treated condition throughout all fermentation periods, whereas protease activity was not significant different from the non treated condition. In addition, the contents of total hexose and uronic acid did not show remarkable change throughout fermentation, but total pentose was decreased by more than 7% at the early middle stage of fermentation(7~14 day after soaking). The change of free amino acid content was decreased by 16~44% than the non treated condition. In contrast, in the YF kimchi, the sensory quality was not good. The activities of amylase, protease, polygalacturonase and gal actosidase were appreciably higher than that of the non treated condition. Meanwhile, the contents of total hexose, total pentose and uronic acid, as products of degradation of cell wall constituents by the above enzymes, were decreased by 18~68% throughout fermentation than the non treated con dition, and total free amino acids were higher than the YS kimchi. Thus, yeast treatment during salting was found to be more effective to extend the edible periods of the kimchi.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.185-189
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• 2007

Quality characteristics of kochujang prepared with strawberry puree (10, 20, and 30% on the total weight basis) were investigated after 30 and 300 days of storage. The moisture content of strawberry kochujang at 300 days was considerably higher than that of strawberry kochujang at 30 days and increasing strawberry content from 0 to 30% significantly increased moisture content of kochujang progressively (p<0.05). Water activity and titratable acidity also showed similar trends, but pH showed the reverse trend with the highest value in control at 30 days and the lowest value in 30% strawberry kochujang at 300 days. As the strawberry puree content increased, amino-nitrogen content consistently and correspondingly decreased. Amino-nitrogen content at 300 days was higher than that of strawberry kochujang at 30 days. Soluble solids content also showed a similar trend, but soluble solid content at 300 days was considerably lower than that of strawberry kochujang at 30 days. Reduction in soluble solids content with increasing strawberry concentration was more evident at 30 days than at 300 day.

• Culinary science and hospitality research
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• v.23 no.8
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• pp.11-16
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• 2017

In this study, two kinds of mealworm seasoning pastes (naturally fermented or inoculation of Bacillus subtilis) were prepared by applying fermentation method of chungkukjang. The samples were labeled into soybean control (SC; no fermentation), mealworm control (MC; no fermentation), mealworm natural fermentation (MR) and mealworm inoculated fermentation of Bacillus (MB). Water content, color, pH, titratable acidity, salinity, amino acid nitrogen, reducing sugar and preference test were examined on the pastes. Moisture contents were 46.9 with soybean control (MC) and 54.5~73.3 with mealworm pastes. The L-value was not significantly different between the samples. In the case of the a-value and the b-value, SC showed the highest value whereas mealworm pastes showed lower values than SC. pH and salinity were higher in mealworm pastes. Amino nitrogen and reducing sugar showed the highest values of MR 326,67 and 63.33 mg%, respectively. In the preference test, the appearance and flavor were the highest values with SC, but texture, taste and overall acceptability were with MR, Therefore, soybean fermentation method with Bacillus species could be applied to use protein of mealworm and possibly edible insects as well.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.348-356
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• 2011

The effects of Glycyrrhiza uralensis and Brassica juncea on the quality and palatability of low-salt gochujang were investigated in terms of the microbial characteristics, enzyme activities, pH, acidity, amino nitrogen and sensory evaluation during 40 days of fermentation. The proliferation of fungi in low-salt gochujang with added G. uralensis and B. juncea were inhibited, while the numbers of total viable bacteria and lactic acid bacteria were not affected. In terms of ${\alpha}$-amylase and ${\beta}$-amylase activity, no significant difference was observed by the salt concentration or additives. However, lowering the salt concentration increased protease activity. The amount of amino-nitrogen in low-salt gochujang at 20 days was similar to that in the control gochujang at 40 days. In the sensory test, low-salt gochujang was preferred compared to control gochujang (8.5% salt). Particularly, the 4.3% salt gochujang with additives was the most preferred.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.3
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• pp.355-363
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• 1996

Physicochemical properties of marketing and intensive persimmon vinegar were investigated, the results are as following; Total acidity in D, H, S, J, sweet persimmon(SP) and persimmon vinegar were 4.20, 3.03, 2.58, 3.30, 5.92 and 5.81%, respectively, and the value of intensive persimmon(IP) vinegars wre higher than that of others. SP sample was lower than any other vinegar as compared to L value in colors, no sample was lower than H and S vinegar inturbidity and browning. Brix of IP samples were lower than that of other vinegars, there was a little fructose in the all samples. Among the organic acids, galacturonic acid content except acetic acid was the highest, and ascorbic and malic acid were detected a little, Calium content was the highest of minerals in persimmon vinegars, phosphorus was detected a little. Alcohols of 5~6 types were analyzed in each samples, free amino acids of 17~24 dypes were analyzed, D and IP vinegars have more acohols and amino acids, and their contents were higher than the others. Volatile components of 6~9 types were analyzed in each samples, these have more ethanols except acetic acids than other volatile components, and the contents of IP samples were higher than that of marketing persimmon vinegars.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.1
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• pp.13-20
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• 1990

Yu Ja cheong(Citron product) one of the traditional drinks was processed by a modified method to improve the quality,. Sugar(38%) and sorbitol(12%) were added as partially substi-tuted sugar and experimented about quality stability during storage at 20$\pm$2$^{\circ}C$ comparing with conventional 50% sugar added product. Chemical compositions of the acidity 40. 46mg% total Vitamin and 28.5mg% amino-N and pH was 3.7 During the storage pH reducing sugar and amino-N contents increased slightly while total acididty decreased slightly and reduced vitamin C occupied most part of total vitamin C after proessing was converted to oxidized vitamin C greatly at 70 days of storage. While L a and b values deceased in between modified one and conventional product. e value increased continually during storage {{{{ {C }_{16 { }:_{ } 0 } }}}} {{{{ {C }_{18 { }:_{ }0 } }}}} {{{{ {C}_{18 { }:_{ }1 } }}}} and {{{{ {C }_{18 { }:_{ }2 } }}}} contnts in fatty acid and citric acid itaconic acid malic acid and succinic acid in organic acid were the major componets in both products. Judging from the results of experiments during storage the quality of the modified product was compared quite well with that of vonventional one during storage.

• The Korean Journal of Food And Nutrition
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• v.32 no.5
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• pp.530-535
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• 2019

In this study, the quality characteristics of 30 kinds of long-term matured soy sauce collected from all over Korea classified according to ripening period were analyzed. The longer the soy sauce had to matured, the closer the pH was to neutrality. Acidity decreased as the ripening period increased. Total nitrogen and amino nitrogen content increased as the soy sauce matured. Moisture content decreased with the increasing soy sauce ripening period, and the content of pure extracts increased in proportion to the ripening period. The numbers of bacteria, fungi, and yeast increased in proportion to the maturation period. The content of P was highest in all soy sauce analyzed, followed by K, Ca, Mg, Fe and Zn. Mg and Ca contents decreased with maturing, whereas K increased with maturing.