The purpose of this study was to investigate the chemical contents (sugar, nitrogen, and amino acids) and sensory characteristics of traditional soy sauce according to three different methods. The samples were taken from four different periods (0, 20, 40, and 60 days after fermentation). Total sugar contents increased in all groups according to ripening period, and Gyupjang (G) showed the highest sugar content among the groups. Total nitrogen and amino acid contents of all groups increased after 60 days of ripening, and Gyupjang (G) and Gyupjang mixed with salt water (SG) had higher total nitrogen content compared to Chungjang (S) at the same period. The results from the sensory evaluation show that preferable sensory characteristics, such as color preferences, sweetness, umami taste, and overall preference, were significantly higher in Gyupjang (G) and Gyupjang mixed with salt water (SG) than in Chungjang (S). Preferable sensory characteristics had significantly high positive correlation with most amino acids, total nitrogen, and sugar contents, except for glutamine. Based on the significant difference in preferable sensory characteristics between Gyupjang mixed with salt water (SG) and Chungjang (S), Gyupjang mixed with salt water (SG) can be used to improve sensory characteristics. This research implies that adding salt water during the manufacturing Gyupjang process is advisable to yield high quality soy sauce.

The core ingredient of traditional Korean style soy sauce is soy bean without any wheat or rice incorporated. National brands as well as regional micro-brewed companies constitute the soy sauce market in Korea. The present study investigated the physico-chemical and sensory properties of soy sauces produced by small-scale or mass-production. Additionally, the key physico-chemical parameters sufficiently representing the critical sensory characteristics have been identified. Ten types of soy sauce brewed by the Korean traditional method were selected for the study. Among these samples, seven types were brewed in small-scales in the Gyeonggi-do region whereas the other 3 types were mass-production products of major national brands. The total solid, reducing sugar, salinity, sugar content, amino nitrogen, CIELAB, acidity, and pH of soy sauce samples were measured for the physico-chemical analysis. A generic descriptive analysis was conducted to analyze the sensory characteristics of the samples using six trained panelists. The descriptive panel developed 21 sensory attributes. The data were statistically analyzed using ANOVA, PCA and PLSR. Overall, the micro-brewed products showed significantly higher value of salinity and acidity but lower content of reducing sugar than the mass-production products. The micro-brewed soy sauces elicited stronger fermented flavor, sourness, and bitterness whereas the national brand products elicited stronger alcoholic odor, sweetness and umami taste. Sugar content, acidity, and amino nitrogen showed strong relationships with fish sauce flavor, umami taste, and rich flavor. Salinity was closely related to the overall flavor intensity.

This study was carried out in order to analyze the changes in nitrogen containing taste compounds of traditional Korean soy sauce with varying Meju concentrations (Meju-water ratios of 1:4 and 1.3:4) and ripening periods (up to 2 years), and to investigate correlation between sensory characteristics and taste compound contents via contents assay and sensory evaluation of soy sauce samples. Nitrogen compound contents were higher in 1.3:4 than in 1:4 for all nitrogen compounds. Free amino acid contents were highest in soy sauce ripened for 210 days. Among amino acids, glutamic acid was highest concentration. Nucleotides and their related compound contents did not vary with concentrations and were highest in the sample ripened for 210 days. In direct sensory evaluation of soy sauce, overall taste preference showed positive correlation to sweet taste. Likewise, overall taste preference showed positive correlation to umami, nutty, sweet taste in the sensory evaluation of seaweed soup seasoned with soy sauce. Sensory evaluation score was higher in 1.3:4 than in 1:4. According to the correlation assay of taste compound contents and sensory evaluations, nitrogen compounds (such as amino type nitrogen), amino acids (such as glutamic acid, aspartic acid, and lysine, and etc.), nucleotides (such as AMP, IMP, and etc) had significant influence on the sensory characteristics of soy sauce, and therefore we can conclude that these compounds affect the taste and quality of soy sauce.

본 연구에서는 상법보다 메주농도를 높게하여 간장을 제조한 후, 2년의 장기 숙성을 거쳐 시료를 제조하고, 메주 농도와 숙성 기간에 따른 맛 특성 변화를 알아보기 위해 간장의 일반 성분 및 당류를 분석하였다. 간장의 일반 성분 중 pH는 4.5~5.3 범위로, 숙성 기간에 따라 감소하였고, 적정 산도는 pH와 상대적인 경향을 보이며 숙성기간에 따란 증가하였다. 총산은 586.145~1008.169mg%로 역시 숙성기간에 따란 증가하였으며, 모두 메주농도 1.3;4에서 높게 나타났다. 완충 작용은 숙성 기간에 따라 유의적으로 증가하였다. 조단백은 6.0681~11.5431 범위로 숙성 기간에 따라 증가하였고, 메주농도 1.3:4에서 그 함량이 높았다. 조지방은 0.03~0.2%로 숙성 초기와 1.3:4에서 함량이 더 높게 나타났다. 수분은 50~70%로 숙성기간에 따라 감소하였고, 식염은 20.54~30.33%로 숙성 기간에 따라 증가하다 2년째는 감소하였다. 순고형분은 숙성 기간에 따라 증가하였고 메주농도 1.3:4에서 더 높았다. 각 시료의 환원당 함량은 숙성기간 도안 완만한 증가를 보였고, 유리당으로는 galactose 261~744mg%, glucose 139.07~339.91mg%, fructose 59.71~168.88mg% 순서로 높은 함량을 나타냈다.

This study was carried out in order to investigate effective aroma components of Korean traditional soy sauce. Volatile aroma compounds were extracted by solvent extraction, TMS esterification of methyl acetate extracts and SDE, and analyzed by GC/MSD. 140 voltile aroma compounds were detected by three different extraction methods. Most abundant volatile compounds were acids and phenols and identified aldehydes, hydrocarbons, ketones, furans, furanone, alcohols, esters, nitrogen compounds, sulfur compounds and thiazoles, too. In the analytical sensory evaluation of soy sauce aroma, there were significant differences between each soy sauce sample in all test item. To sum up, Sweet odor was high in Kyupjang. Nutty odor and traditional soy sauce odor were similarly high in Kyupjang and high concentration soy sauce. Kyupjang had high score in overall odor preference than Chungiangs. The result of multiple regression of soy sauce odor characteristics and gas chromatography pattern demonstrated that offensive and sour odor was affected by octadecanoic acid. Contributive compounds to sweet odor were 1,2-benzenedicarboxylic acid and 3,6-dioxa-2,7-disilacotane. Benzoic acid 4-methyl ethyl ester and nonacotane were identified as major compounds of nutty odor. Contribu live variables of traditional soy sauce odor were benzoic acid 4-methyl ethyl ester and 9,12-octadecadienoic acid. The main factors of odor preference were 3-methyl pentanoic acid, acetic acid, 2,6-dimethyl heptadecane and 3,6-dioxa-2,7-disilacotane.

This study was carried out in order to analyzed the changes in nitrogen containing taste compounds of three different types of traditional Korean soy sauce with varing ripening period, and to investigates correlation between sensory characteristics and taste compounds contents via contents assay and sensory evaluation of soy sauce samples. Total nitrogen, ammonia type nitrogen and amino type nitrogen contents showed the highest value in Kyupjang. 17 kinds of free amino acid was detected in Chungjangs and 16 kinds of free amino acid was detected in Kyupjang. Nucleotides and their related compounds detected were hypoxanthin, xanthin, IMP, AMP, Inosine, ADP. Free amino acid and nucleotides and their related compounds contents were highest in Kyupjang. Nitrogen related compounds content of high concentration soy sauce ripened over 150 days increased similarly with Kyupjang. In the sensory evaluation of soy sauce taste, Chungjang samples acquired the highest score in the offensive taste test while Kyupjang marked highest score for sweet taste, nutty taste, taste preference. High concentration soy sauce ripend over 150 days yielded the result similar to that of Kyupjang. Sweet taste showed positive correlation with nitrogen compounds. The materials that showed positive correlation with nutty and traditional soy sauce taste and taste preference were nitrogen compound, IMP, AMP. Except for tryptophan, all free amino acid showed positive correlation with nutty and traditional soy sauce taste. Particulary, taste preference correlated to lysine, aspartic acid and glutamic acid.

This study was carried out in order to investigate general characteristics, sugars and organic acids contents of Korean traditional soy sauce, and to find out possibility of high quality soy sauce production in a short period through high concentration soy sauce making. In this study, we prepared three different types of soy sauce, low concentration soy sauce (Chungjang), high concentration soy sauce and Kyupjang, high quality traditional Korean soy sauce. pH of soy sauce were 4.46~4.90 and did not show difference among three samples. Titratable acidity, buffering power and total free acid content were the highest value in Kyupjang. Kyupjang showed the highest contents of salt and pure extract. As the ripening period increased, the salt content increased in Chungjang samples, but decreased in Kyupjang. Reducing sugar contents of Kyupjang, high concentration soy sauce and low concentration soy sauce were 1.13%, 0.76% and 0.53%, respectively. Free sugar in soy sauce were analyzed maltose, glucose, galactose and fructose. Total free sugar content was highest in high concentration soy sauce, however, contents of glucose and fructose were higher in Kyupjang than in Chungjang samples. Galactose was the main free sugar in Chungjang, but glucose was in Kyupjang. Among identified volatile organic acid, acetic acid was present in the highest concentration, and volatile organic acid content was highest in the high concentration soy sauce at 150 days. 20 nonvolatile organic acids were detected in Korean traditional soy sauce. Succinic acid, lactic acid and 2,5-pyridine dicarboxylic acid were the main nonvolatile organic acid in soy sauce.

본 연구에서는 한국 전통 간장의 담금용기를 달리하였을 때와 메주의 농도를 상법보다 높게 하였을 때의 질소성분 함량과 향기성분을 분석하고 향미의 관능검사를 실시한 후 향기성분 패턴과의 통계적 해석을 통해 어떠한 성분이 간장의 관능 특성에 영향을 주는지 알아보았다. 본 연구에서 얻은 결과들을 요약하면 다음과 같다. 1. 간장의 맛에 가장 큰 영향을 미치는 요인으로 평가되고 있는 질소성분의 함량에서, 총질소의 경우는 메주의 농도와 상관없이 유리병이 항아리보다 높았으며 메주의 농도가 높은 경우 많은 양을 함유하는 것으로 나타났다. 그러나 유리병은 항아리보다 적은 양의 amino태 질소와 더 많은 양의 ammonia태 질소를 함유하고 있어 질적인 면에서 떨어지는 것으로 나타났다. 2. 유리아미노산의 함량을 조사한 결과, 총유리미노산의 함량은 150일 이후 최고치를 보였다. 지미와 감미를 내는 glutamic acid, aspartic acid, serine, alanine, Iysine의 함량이 높게 나타났고, 쓴맛에 관여하는 valine, phenylaalanine, leucine, isoleucine의 함량도 높게 나타났다. 3. 휘발성 유기산으로는 acetic acid가 가장 많이 함유되어 있는 것으로 나타났고 항아리가 유리병보다 함량이 높았으며 메주농도 1 : 4는 완만한 증가를 보이나 1.3 : 4는 숙성기간 150일에 급격한 증가를 나타냈다. 고린내의 주요성분으로 알려져 있는 butyric acid는 유리병 1 : 4와 항아리 1.3 : 4가 비슷한 경향을 보였으며 유리병 1.3:4에서는 급격하게 감소하였다. 그러나 모든 군에서 숙성기간이 경과할수록 감소하는 일정한 경향을 보였다. 이 외에 valeric acid와 capric acid가 소량씩 함유되어 있는 것으로 나타났다.