• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.76-81
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• 1990

For the determination of principal taste components in L. chinensis M., A. acutiloba K., S. chinensis B. and A. sessiliflorum S., which were extracted with water and ethanol, contents and composition of free sugars, free amino acids, non-volatile organic acids and tannins were analyzed. The extraction yield of them was high when using the water as an extraction solvent, the optimal ethanol concentration with high yield was in the range of 50-75%. The contents of free amino acids in their extract $(25^{\circ}Bx)$ was high when using the ethanol as the extraction solvent. The amino acid content was in the range of 123-159 mg%. in samples. The free sugar of extracts contained 2-12% in samples which were consisted of glucose, fructose and sucrose. The pH and acidity range of extracts were 4.4-5.1 and 1.01-2.27% respectively, and especially extracts of S. chinensis B. showed to be strong acid as pH 2.9 and addity 11.93%. The composition of non-volatile organic acid in extracts of S. chinensis B. contained citric acid and malic acid 3.90% and 3.92% respectively as major components. The tannin content of extracts was considerably high when extracting with 50% ethanol, especially A. sessiliflorm S. contained $3.35%{\sim}3.85%$.

• Food Science and Preservation
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• v.18 no.4
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• pp.508-516
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• 2011

The chemical components (e.g., proximate composition, nucleotide-related compounds, and amino-acid content) of raw, dried, and boiled giant squids were investigated. The moisture contents of raw, dried, and boiled giant squids were 75.65, 39.75, and 41.12%, respectively. The boiled giant squid had a higher moisture content than the dried giant squid. The crude protein contents of raw, dried, and boiled giant squids were 20.10, 56.25, and 49.58%, respectively, with that of the dried giant squid higher than that of the boiled giant squid. The crude lipid contents of the raw, dried, and boiled giant squids were 0.15, 0.57, and 1.35%, respectively, with the boiled giant squid having the highest crude lipid content. The crude ash content of raw, dried, and boiled giant squids were 1.68, 4.50, and 6.77%, respectively. IMP content was detected in the dried (1.21 mg/100 g) and boiled(0.25 mg/100 g) giant squids. In the sensory scores, the degree of bitterness, acidity, and aftertaste had lower values in the dried and boiled giant squids than in the raw giant squid. A total of 18 amino acids were detected in the samples, and most of the samples had high contents of glutamic acid, aspartic acid, proline, and arginine and low contents of histidine, tyrosine, and methionine. The free-amino-acid content was related to the taste component. The major free amino acid contained by the samples were hydroxyproline, alanine, arginine.

• Food Science and Preservation
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• v.16 no.6
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• pp.893-899
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• 2009

We compared the physicochemical properties of commercial brown rice vinegar fermented with and without ethanol. The pH and total acidity did not significantly differ between the two types of vinegar. Sugar content, reducing sugar content, and free sugar concentration were higher in commercial brown rice vinegar fermented with ethanol, whereas browning, turbidity, and overall color darkness were higher in vinegar fermented without ethanol. The ratio of acetic acid to total organic acids was 0.94 - 0.96 and 0.97 - 1.00 in commercial brown rice vinegar fermented with or without ethanol, respectively. A higher content of total amino acids, 93.07 - 509.48 ppm, was found in vinegar fermented without ethanol. Fermentation conditions affected the physicochemical properties of brown rice vinegar, as shown by significantly higher $\gamma$-aminobutyric acid (GABA) content in brown rice vinegar fermented without versus with ethanol.

• The Korean Journal of Food And Nutrition
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• v.33 no.4
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• pp.381-389
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• 2020

The purpose of this study was to evaluate the appearance, physicochemical, physical, and fermentation properties of the fermented soybean produced by manufacturing with inoculation the different types of microbial strains. The strains were inoculated by the NSI (natural strains inoculation), and the SSI (selective strain inoculation) were treatments. The appearance showed differences in color, viscous substance, and hardness depending on strains inoculation and fermentation duration. The pH, and total acidity were 6.40~7.26%, and 0.10~0.39% respectively with differences depending on the samples. The moisture content as the fermentation duration increased, the NSI (56.03~57.66%) decreased and the SSI (56.71~58.63%) increased. The physical characteristics of the hardness increased as the fermentation duration increased for the NSI and the SSI decreased. The color values for the L, a, and b values were 47.64~58.56, 7.15~9.08, and 12.41~17.30, respectively. The α-amylase and protease activities of the SSI were the highest among all treatments. The total viable cell counts of the fermented soybean products by strains were 5.02 to 9.77 log CFU/g, and SSI (fermentation, 48 hours) was the highest. The amino-type nitrogen contents of all samples were 301.62~746.97 mg% and the SSI showed the highest content. The amino acid had the highest glutamic acid content.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.704-708
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• 1994

This study was performed to compare quality of citron juice as affected by the extraction method. The yield of citron juice was 24.49% by method I (rotary-crushing and screening), 18.09% by method II (pressing) and 12.60% by method III (belt-pressing), respectively. Juices by methods I and II had more soluble solid contents and essential oil and pulp volume than that by method III. Method III was higher in titratable acidity than methods I and II. The contents of fructose, glucose and sucrose in method III were 0.54%, 0.37% and 1.11%, respectively, which were lower values than those in other methods. But there was no siginificant difference in the contents of total sugar by the extraction method. For fatty acids composition, the contents of oleic acid in method I, palmitic acid, linoleic acid and linolenic acid in method II, and stearic acid in method III, respectively, were highest when compared with other methods. The contents of free amino acids detected in method III were smaller than those in methods I and II. Threonin was detected only in method I, methionine and cystine were not detected in methods I. II and III. But the contents of the total amino acids in method III were $1.3{\sim}1.6$ times as large as those in methods I and II.

• Korean Journal of Microbiology
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• v.7 no.4
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• pp.153-158
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• 1969

It is the most important thing to substitute sweet potato for wheat flour as the brewing material of Maggerley(Korean wine) in order to save precious wheat flour which is now consumed as the sole material in it. In this study, the fermenting mash material has been prepared with combination of wheat (KIorean wine) as a first step of sabing wheat flour consuming. The combination ratio of wheat flour and sweet potato starch in mashing, in this experiment, are such as mashing plot of 100% wheat flour (No.3 plot), 50% wheat flour plus 50 % of sweet potato starch (No.2plot), 30% wheat flour plus 70% starch syrup of sweet potato (No. 4 plot), and 60% wheat flour plus sweet potato starch (No. 1 plot). The results of fermentation and chemical components of each mash in experimental plot are as following : 1. Alocholic fermentation was most vigorous in No.4 plost among them, the next are in order to hydrolyze and break down the protein sourece to glucose and amino acid, the new enzymic source were added in experimantal amsh before putting yeasts, those enzymic sources have been developed and prepared in this laboratory No.4 and No.2 plot at same degree. Generally, the activities of alcholic fermentation of all plots are vigorous and fair. The acidity of each fermented mash is in the rangw of 3.7-4.8. 2. Amounts of amino acids in fermented mash are in the range of 145 mg per 100 ml and 158 mg for all experiments, and these amounts are much more than those of present commerical Maggerley. However, the amount of it in the No.4 plots is much less among the m, this is due to the lack of protein source in starch syrup. 3. Amounts of organic acids in fermented mash are in the range of 0.44g per 100ml and 0.62g, these amounts are generally much more than those of the present commercial Maggerley. 4. The result of sensory test for the experimental Maggerley shows good taste and flavour in comparison with those of commercial Maggerely. 5. It is proved that these experimental fermentation of Maggerley is succesful in the partial substitution of sweet potato starch potato starch for wheat flour, and it is also be able to make a good Maggerley in all aspects of quality.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.227-236
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• 1986

Three types of Kochujang(soybean-red pepper paste) were prepared with glutinous rice flour (group A), glutinous rice grain (group B) or the mixture of flour and grain (group C) to investigate some chemical composition, enzyme activities and the texture during aging period. 'There were no remarkable differences in the contents of moisture, crude protein, crude fat, minerals and alcohols, titrable acidity and pH among the tested groups. Amino nitrogen content, acidic protease and saccharogenic amylase activities were measured to be higher values for group A whereas reducing sugar content higher values for group B. All tested groups contained Ca, Cu, K, Mn, Mg, P and Fe, particularly higher amount of K but a trace of Cu, Mn and Fe. All tested groups showed higher content of aspartic acid, glutamic acid, cystine, proline and lower content of histidine and valine 60 days after the preparation. The total free amino acid content was 16.49 mg/g for group A, 13.68 mg/g for group B and 15.84 mg/g for group C. The measurement of texture showed high values of hardness and adhesiveness with group A immediately after the preparation and with group B at the end of aging. Cohesiveness and springiness were high with group A while low with group B throughout aging period.

• Microbiology and Biotechnology Letters
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• v.45 no.3
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• pp.218-225
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• 2017

Saeu (shrimp) jeotgal (SJ) was prepared by mixing with 25% salt with different types: purified salt (PS), solar salt aged for 1 year (SS), and bamboo salt. SJ was fermented for 22 weeks at $15^{\circ}C$. Bacilli and marine bacteria were detected throughout the entire fermentation period, and marine bacteria were present in the largest numbers. Lactic acid bacteria (LAB) were detected only during the first 8-10 weeks, but yeasts appeared at the sixth week and later. Archaea were detected in low numbers only from SS-SJ during the first 8 weeks. BS- SJ showed higher pH and lower titratable acidity (TA) values than other SJs because of strong alkalinity of bamboo salt. Amino-type nitrogen (ANN) contents of SJs increased during fermentation, especially, after 2 and 6 weeks. SS-SJ showed the highest ANN content from the beginning to the end of fermentation. Ammonia-type nitrogen (AMN) contents also increased like the amino-type nitrogen during fermentation. The highest volatile basic nitrogen (VBN) was also observed in SS-SJ. Salinity was kept constant after 4 weeks. SS was better than other salts for SJ fermentation in terms of protein hydrolysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1543-1548
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• 2014

To study traditional Doenjang characteristics, Doenjang was purchased from five different provinces: Chungcheong (CC), Gangwon (GW), Gyeonggi (GG), Gyeongsang (GS), and Jeolla (JL). To determine physicochemical characteristics, contents of reducing sugar, amino type nitrogen, salt, pH, and acidity were analyzed. The sensory characteristics were analyzed by sensory descriptive analysis. Reducing sugar content was highest for Doenjang from GW province. Amino type nitrogen content was highest for Doenjang from JL province. The salt content was highest in Doenjang from CC and GS provinces. After principal component analysis (PCA) based on sensory descriptive analysis, salty taste and aftertaste were highly correlated with overall acceptance. In the correlation analysis among chemical compounds and overall acceptance, Doenjang contained low reducing sugar content, and high pH value was positively correlated with overall acceptance. In conclusion, Doenjang with high pH value and salty taste and aftertaste have high overall acceptance.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.286-295
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• 2017

This study was performed to develop a liquid flavoring material from Tenebrio molitor larva by using Aspergillus oryzae. T. molitor with 1% A. oryzae for 48 hours yielded the highest protease activity. Different salt concentrations and rice flour addition affected the fermentation characteristics for 90 days. LN (low salt, rice flour non-addition) yielded high protease activity, and total nitrogen and amino-type nitrogen contents. LN showed Glu accounting to 15.16% of the free amino acids and yielded high scores of sweet and savory taste, and overall acceptance after 90 days. Rice flour addition group showed high content of total and reducing sugars with high amylase activity, however, low salt concentration had more effect on sensory acceptance than rice flour addition had (p<0.05). All samples had total acidity <1% and LN (90) showed the highest browning index and aroma intensity, as noted from maillard reaction, as well as good sensory acceptance.